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Chapter 1 | Introduction: Our Cosmological Roots | |
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In all of us there is a hunger, marrow deep, to know our heritage, to know who we are, and where we have come from. Without this enriching knowledge, there is a hollow yearning. No matter what our attainments in life, there is a vacuum, an emptiness, and a most disquieting loneliness. Alex Haley, Roots |
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The realities of nature surpass our most ambitious dreams. Rodin |
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Online Edition
2001, 2004, 2011, 2013 copyright Ronald C. Pine |
Our Home in the Universe | |
By the time you finish reading this sentence you will have moved over 150 miles. The seemingly stable ground beneath your feet is actually hurtling through space at a colossal speed in many different relative directions. We live, in the words of the poet Walt Whitman, on "a great round wonder rolling through space," a spinning sphere whirling around at approximately a thousand miles per hour at its midsection, the equator. Our Earth home completes one rotation in twenty four hours and continues this process 365 times before sweeping out an enormous elliptical path around our Sun. To complete this path the Earth moves at 18 1/2 miles per second or 66,000 miles per hour.1 And this is not all. Our Sun is moving at the incredible speed of over 150 miles per second or over 540,000 miles per hour, taking the Earth and other planets of our solar system on a mysterious journey through space and time, as it sweeps a 250 million year path around our galaxy. | ||
Men and women are not content to comfort themselves with tales of gods and giants, or to confine their thoughts to the daily affairs of life; they also build telescopes and satellites and accelerators, and sit at desks for endless hours working out the meaning of the data they gather. Steven Weinberg, The First Three Minutes | On a small piece of this spinning ball, on
the island of Hawaii, the largest island in the chain of
islands that make up the State of Hawaii, are two of the
largest volcanoes on Earth, Mauna Kea and Mauna Loa. On
the top of Mauna Kea are human structures symbolizing much
that is right about human nature (Figure 1-1). Because
this location offers the best astronomical viewing
conditions in the world, the United States, the United
Kingdom, Canada, France, Japan, Argentina, Australia,
Brazil, Chile, and the Netherlands have assembled here
multimillion-dollar monuments to that human
characteristic responsible for much of our present
success on this planet, our curiosity. When truth and
objectivity are important, international collaboration
is a necessary practice. Here astronomers from
many countries and cultures peer out into the blackness
of the night, attempting to understand the secrets of
places trillions of miles away, attempting to understand
the details of our cosmological roots, of who we are and
where we have come from. At almost 14,000 feet above sea
level (above nearly half of the Earth's obscuring
atmosphere), the summit of Mauna Kea is actually 32,000
feet from the ocean floor. These massive mountains were
created by lava pouring out of a "hot spot" in the ocean
floor, a hole in the Earth's crust estimated to be
almost 200 miles long and over 100 miles wide. Few who
visit these volcanoes fail to be awed by this silent
testament to the potential power of nature, and
astronomers are very grateful for nature's construction
of these formidable platforms. |
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In relative terms, however, these volcanoes
are very small. On Mars there is a single volcano larger
than the entire Hawaiian island chain. Figure 1-2 shows a
superposition of this monstrous extraterrestrial volcano,
called Olympus Mons,
the Hawaiian island chain, and Hurricane Iwa. Hurricane
Iwa hit the islands of Kauai and Oahu in 1982. Terrorizing
these islands for only a single day, its size and power
were an unexpected shock to people who took for granted
gentle breezes and balmy weather. Some pampered residents
were indignant that they had no electricity for a few days
afterwards. Perhaps they should have kept things in better
perspective. The next picture (Figure 1-3), taken by
the Voyager
spacecraft in March, 1979, shows the famous Red Spot on
the planet Jupiter. This gigantic hurricane, the size of
several Earths, has been observed from Earth for over 300
years, and some estimate that it may be a million years
old! The top speeds of the winds of hurricane Iwa reached
110 miles per hour. Those on Jupiter reach over 300 miles
per hour.
We are all astronauts. As we sail on through an immense sea of seemingly indifferent space, as we work and play, experience success and defeat, happiness and sadness, as the trials and tribulations of humankind are carried out on this little bluish ball, we fail to recognize for the most part our cosmic setting. Consider the unheralded fact that it is impossible for any of us to go home again to an exact mathematical spatial point of our childhoods. Some time ago I returned to where I lived as a child, to Southern California, a town called Garden Grove about five miles from the original Disneyland. I sought out and found my old street and house. |
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The unexpected and the incredible belong in this world. Only then is life whole. Carl Gustav Jung | It was a haunting experience walking down that street. Because my memories were mostly of childhood experiences, everything seemed so much smaller now, except for the mature trees in each of the front yards. I found my old house and stopped in front of the short cement driveway. Here was where I found my dog dead in the street, apparently run over by a car. I was sure he was only sleeping and carried him to the backyard and put a blanket over him. I had no concept of death yet and could not understand why he did not get up the next day, and why his body was so stiff. Here was where I parked my first car and experienced the uncertainty of adolescence. It was a strange experience being at a place that I had not been to for over thirty years. | |
Stranger still is that, in a sense, I had actually not been "here" before at all. Since I had lived on this street, the Earth had spun on its axis like a top 11,000 times, completing over 30 sweeping journeys around the Sun, all the while being carried by the Sun over 140,000,000,000 miles from the original relative mathematical point2 of my childhood experiences! This was not home, it was only a reminder of home. | ||
The deflation of some of our more common conceits is one of the practical applications of astronomy. Carl Sagan | Such an astonishing distance, but actually no more than a trivial speck of what scientists call space-time -- a mere .00000012 of the distance our Sun will travel in its course of one revolution around our galaxy. To have some idea of the vastness of our cosmic home, let's leave our Earth and take a brief imaginary trip into deep space. Not far from our Earth, a mere 250,000 miles, is the Moon. Although that distance is equivalent to driving a car around the entire Earth 10 times, the Moon is part of our cosmic backyard. Once upon a time (1969-1972) humans were able to travel to this place in a few days and witness Earth rises (Figure 1-4). | |
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Approximately 93 million miles away is an object of great importance to our continued existence, our Sun. If we could drive in a magic car at a steady speed of 60 miles per hour, it would take 175 years to reach the Sun from the Earth. The Sun is over 300,000 times more massive than the Earth, weighs about 2.2 billion billion billion tons, and a million Earths could easily fit within its volume. Its surface temperature averages almost 10,000 degrees Fahrenheit. We are very fortunate that it is just this size and just this distance away, or our Earth could have suffered a climatic catastrophe similar to those of the planets of Venus and Mars. A little closer and our planet would not be the biological haven that it is. Perhaps it would be more like Venus (about 70 million miles from the Sun) where the temperature is over 800 degrees Fahrenheit. A little further and our planet might be like Mars (about 140 million miles from the Sun), a very cold desert. | |
The sun rises. In that short phrase, in a single fact, is enough information to keep biology, physics, and philosophy busy for all the rest of time. Lyall Watson, Lifetide | Life is possible on Earth due to the particles of light from the Sun scientists call photons. By the time they reach us they have had a very long journey. Created through cataclysmic nuclear processes in the deep interior of the Sun, photons require tens of thousands of years to finally escape this massive turmoil. Once they escape, they speed away from the Sun at 186,000 miles per second, some (a small fraction of the total) reaching the Earth in little over 8 minutes, allowing tourists on Waikiki Beach to get tans, and plants and microorganisms to harvest this energy through photosynthesis, starting the food chain that is essential to most life on Earth. | |
About 100 billion solar neutrinos pass through your thumbnail every second. Astrophysicist John Bahcall |
Particles of light are very small.3
Millions are required to make up a faint stream of light.
Neutrinos, another kind of particle generated by the Sun's
nuclear furnace, are even smaller. Trillions are at this
very moment passing through your body and surrounding
Earth, either through the top of your head, if it is
daytime, or through the bottoms of your feet, if
nighttime. They pass through our bodies and the solid
Earth as if our bodies and the Earth were a universe of
empty space. (Capturing neutrinos is thus very
difficult. To see how physicists do it, click here.)
Nuclear physicists estimate that approximately 4 million tons of the Sun's nuclear fuel are consumed every second to produce the energy stream that allows for life on Earth. This energy output is equivalent to most of the world's electrical energy production multiplied by a million years, and the process has been ongoing for about 5 billion years and will continue for at least another 4 billion years.4 As important as this star is to us, it is simply a grain of sand in an enormous sea of stars and galaxies. It is important to reflect that the next nearest star to us is about 300,000 times more distant than our Sun. Our Sun is part of a single galaxy of stars. Within our galaxy there may be up to 400 billion stars. Although our Sun is a little above average in terms of size, temperature, and brightness, it is still often referred to as a yellow dwarf star. Although a million Earths could fit within the Sun, the supergiant star Mu Cephi could hold a billion Suns! |
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Walking home at night, I shine my flashlight
up at the sky. I send billions of ... photons toward
space. What is their destination? A tiny fraction will
be absorbed by the air. An even smaller fraction will
be intercepted by the surface of planets and stars.
The vast majority ... will plod on forever. After some
thousands of years they will leave our galaxy; after
some millions of years they will leave our
supercluster. They will wander through an even
emptier, even colder realm. The
universe is transparent in the direction of the
future. Hubert
Reeves, Atoms of Silence |
Figure 1-5 shows
what astronomers call the Eta Carina Nebula. This
is a view from within our galaxy; stars that appear close
together are actually trillions of miles apart. On this
scale our entire solar system, the area within the orbit
of the now considered dwarf planet Pluto, approximately 7
and 1/2 billion miles across, would be but a tiny dot on
this photograph.
We have sent our spacecraft out into this colossal cosmic neighborhood, but it will be a very long time before they travel very far. Pioneer 10 is such a spacecraft. Launched in March of 1972 and traveling now at a little over 7 miles per second (25,000 miles per hour), it did not cross the orbit of the outermost planet of our solar system until June 1983, and it will not reach the vicinity of a relatively close star for 33,000 years.5 Since this star is moving towards us at a very rapid closing speed, Pioneer's journey is shortened by over 200,000 years. The little spacecraft was designed to last for only two years, but it was still transmitting information back to Earth in March of 1996 when funds were finally cut off to monitor its signals. Talking about large astronomical distances in terms of miles or kilometers is very inconvenient. The distances between cosmological structures like stars and galaxies are more easily judged by using the standard of a light year, the distance light travels in one year. At about 186,000 miles per second, 670 million miles per hour, or 16 billion miles in one day, a single light year is equal to 6 trillion miles. The distance then from the Earth to the nearest star is about 4 light years.6 With the flights of Pioneer 10 and 11, and Voyager 1 and 2 in the 1970s, we explored some of the objects within our solar system. Launched in the Fall of 1977, Voyager 1 arrived at Jupiter in March of 1979, about a half billion miles from the Sun and a little over 400 million miles from the Earth. This year-and-a-half journey was a marvelous technological achievement, but what human technology accomplished in a year and a half, nature accomplishes in about 36 minutes at the speed of light. Voyager then traveled to Saturn, a distance of almost a billion miles from the Sun. It arrived in November of 1980, and then left our solar system. Voyager 2 followed a different path, arriving at Jupiter in July of 1979, Saturn in August of 1981, Uranus in January 1986, a distance of about 1.8 billion miles, and Neptune in 1989, a distance of 2.8 billion miles. Voyager required 12 years to accomplish this journey, even though it traveled at about 60,000 miles per hour. A beam of light would require only the time between your breakfast and lunch. Jupiter is the largest of all the planets. Over 1,000 Earths could fit within its volume. After the Voyager flights planetary scientists had theorized that this gigantic world has no solid surface, but that deep beneath its frigid ammonia clouds there is an enormous ocean of hydrogen and, very deep and under enormous pressure, a core of liquid metallic hydrogen. On December 7, 1995 a probe from the Galileo spacecraft plummeted into Jupiter's turbulent atmosphere. Lasting for only about an hour before the probe was crushed and melted by the tremendous pressure and temperature, it sent back data to the orbiting Galileo mother ship that humbled scientists who expected to find more water in the cloud tops and some evidence to confirm their theory of the planet's formation. The four, historically important, Galilean moons of Jupiter -- Io, Europa, Callisto, and Ganymede -- so called because they were discovered by Galileo in 1609, were surveyed for the first time by the Voyager flights. |
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Somewhere, there is
something incredible waiting to be known. Carl Sagan. In many ways the meandering path of our understanding is like a enduring but somewhat turbulent romance where each idea is a gesture to the universe for acceptance . . . . But why we seek to understand is no mystery. It is as natural for our species as love. |
Io is the
first body in the solar system other than our Earth where
active volcanoes have been observed. Pictures from Voyager
revealed at least eight active volcanoes and enormous
volcanic explosions, spewing solid material up over 60
miles, a distance much larger than that of the eruption of
Mt. St. Helens. Some of the
eruptions were observed to last for four months. Updated
pictures from the Galileo spacecraft in 1999
showed Io to be the most active volcanic location in the
solar system with over 100 active volcanoes. The
massive volcano Loki is likely the most powerful in the
solar system with a caldera full of lava the size of the
state of Maryland. Io may harbor a global ocean of magma
beneath its surface, with brief sulfur dioxide clouds
caused by the volcanic eruptions, sulfur snow storms, and
perhaps even lakes of liquid sulfur on its surface.
Europa, the brightest of the Galilean moons, is about the size of the Earth's Moon, but unlike our Moon its surface shows few impact craters. Instead the surface appears completely covered with ice and mobile ice sheets, implying a very active surface environment. Although ice volcanoes or geysers have not been observed yet, ice flows were observed by the Galileo spacecraft and planetary scientists believe that such volcanoes or geysers have caused the flows, spewing into space pressurized water from a possible huge underground ocean that quickly freezes and then falls back to the surface, in the process erasing any craters. In 2013 the Keck II telescope in Hawaii captured infrared data that indicated magnesium sulfate salt deposits on the surface, strong evidence for an ocean below the ice surface. Compared to the Earth's oceans, up to 7 miles deep, planetary geologists have calculated a 60-mile deep ocean underneath Europa's icy surface. Ganymede, the largest moon in the solar system, is larger than the planet Mercury and 40% larger than our Moon. Ganymede is the only moon known to have a magnetic field. Density measurements also indicate a large amount of water or ice as a basic constituent. Could it also have a large underground ocean? Yes, as indicated by magnetic data received from the Galileo spacecraft. Perhaps an ocean as salty as the Earth's (salty minerals have been detected on the surface) about 125 miles below the surface. These possibilities have fired the speculative imagination of many scientists. Could there be some form of life in these oceans? What would it be like? Recently, biologists have realized that life is much more tenacious than previously thought. Biologists specializing in deep life have discovered bacteria living up to five miles within the Earth's crust, some thermophiles (heat lovers) such as Bacillus infernus can survive temperatures over 165 degrees F (74 degrees C), and we now know that very large, and very strange, worm-like creatures live around hot vents at great dark depths in the Earth's ocean. Far from the energizing rays of light from the Sun, the worm-like creatures, called Riftia, grow to several feet in length, but have no mouth, gut, or anus. The discovery of these creatures surprised biologists initially, because the hot waters emanating from these vents supply the energy to sustain a food chain that does not rely on the energy from the Sun as does most life on Earth. In Riftia's case, it feeds off the productivity of an enormous number of bacteria that live inside its body! Given that the hot rocky centers of Europa and Ganymede, plus the gravitational flexing caused by Jupiter, would supply abundant heat, similar life could exist under the thick ice crusts of these moons.7 The fourth Galilean moon is Callisto, the most
heavily cratered object in the solar system. Unlike Io
and Europa, which seem to have recovered from the
meteoric bombardment that scientists believe was part of
our solar system's creation billions of years ago, like
the Earth's Moon, Callisto remains scarred and wounded
with thousands of craters. Its surface has probably
changed little in the last 4 billion years. Although to
a far lesser extent, such bombardments continue to this
day throughout our solar system. Not far from Winslow,
Arizona is the mile wide, over two hundred yards deep, Meteor Crater, a result of a
relatively small asteroid collision with the Earth
50,000 years ago. The force of the impact was equivalent
to a 15-megaton nuclear explosion. In July 1994, several
pieces of a disintegrating
comet, that would have easily destroyed all life
on Earth, slammed into Jupiter with a force estimated at
40 million megatons, 500 times more explosive power than
all the world's nuclear weapons at the time. Callisto
and our Moon remind us not only of our solar system's
violent past, but also of our unpredictable future and an important philosophical concept -- our
contingency. We are
contingent creatures, as is all life on Earth. An immense number of events
had to be just right historically to produce the
conditions for our existence and there is no central
or protective guarantee for human flourishing in a
vast and formidable universe. |
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Two years later, and another 500 million miles, Voyager reached majestically ringed Saturn. Although 15% smaller than Jupiter, Voyager's encounter with this planet was not without many surprises. Many more rings were discovered than Earth-based observations had indicated, and a spoke-like, braiding effect between some of the rings was observed that had initially no known gravitational explanation. Saturn's beautiful rings stretch 170,000 miles tip to tip, but are so thin that for a few days every 15 years the rings become difficult to see from the vantage point of Earth as the edges align. Saturn is essentially a huge ball of weather with winds up to 1,000 miles an hour. It requires almost 30 Earth years to revolve around the Sun, but its day is only 10 1/2 hours long. | ||
Everything that you could possibly imagine, you will find that nature has been there before you. John Berrill. | Saturn's major moon is Titan, a very large moon, perhaps
larger than Jupiter's Ganymede. Prior to 2005 it was
difficult to tell, because the atmosphere is so dense
(much denser than that of Earth) that planetary
scientists, much to their disappointment, were unable to
make out any surface features of Titan as Voyager
flew by. With the exception of the basic chemical facts --
Titan
has large amounts of nitrogen and methane, and small
amounts of ethane, acetylene, ethylene, and hydrogen
cyanide -- scientists were left with only their
imaginations and various paths of speculation. Might the
surface contain the same biochemical soup that made the
origin of life possible on Earth? How about rivers,
waterfalls, and oceans of methane? Perhaps on Titan
there would never be an energy problem, because the rain
consists of oil rather than water. By 2005 some
questions were answered. The Cassini-Huygens
spacecraft arrived at Saturn in July 2004. The
Cassini orbiter surveyed Saturn and its moons for four
years and the Huygens probe plunged into the atmosphere of
Titan in January 2005 and landed on its surface. It
now appears that methane lakes and rivers are dominant
features of this moon. When Voyager 2 encountered Uranus, it discovered on the moons some of the strangest geological features known in the solar system, and a probable gigantic 5,000 mile deep ocean of water mixed with ammonia on the planet itself. Although at its cloud tops the temperature is minus 360 degrees Fahrenheit, the ocean surrounding a hot core about the size of the Earth is estimated to be about 8,000 degrees Fahrenheit. On the moon Oberon is a mountain that is at least 12 1/2 miles high, over twice the height of Mt. Everest. Miranda's geology is so strange, planetary scientists speculate that like a Humpty Dumpty that was fortunate to be put back together again, it was blasted apart in the past by a cataclysmic impact with an object about half its size and then was reformed ("reaccreted") by gravity. Uranus itself is tipped on its side, such that its north and south poles face the Sun like a large bull's eye at different times during a Uranus year. After Neptune, Voyager
2's next milestone will be the star Sirius.
Although the brightest star in the Northern Hemisphere
and relatively close to Earth (14 light years), traveling
a little slower now at about 40,000 miles per hour, Voyager
will require some 350,000 years to reach the vicinity of
this star, passing within several trillion miles. The
nearest star system to our Sun, Alpha Centauri, is about
four (4) light years or about twenty-four trillion
miles. Don't get lost in the numbers. For
perspective, imagine if this distance was the distance
between the Disneyland in Orlando, Florida and the
Disneyland in Anaheim, California (over 2,000 miles).
Even though Voyager
2 was launched
from Earth in 1977 and is now traveling faster than the
astronauts when they returned from the Moon (26,000
m.p.h.), it would have traveled only one mile between
the two Disneylands. Over 2,000 years then to just
reach the closest star system to our Sun. Our
solar system is just an astronomical backyard. Finally, by July 2015 the New Horizons spacecraft
reached Pluto after a 3 billion mile journey. The
spacecraft was launched in January 2006, when Pluto was
still considered the ninth planet. Now classified
as a dwarf planet8 and technically
part of what is called the Kuiper belt -- a realm of
trillions of comets and other dwarf planets similar to
Pluto -- from the first close up pictures planetary
geologists were very surprised to see 11,000 foot tall
ice mountains and very few impact craters. Also a
surprise, a nitrogen atmosphere, but because of its
small size, planetary scientists estimated from the
detection of nitrogen ions by the spacecraft far from
the planet's surface that about 500 tons of the
atmosphere were lost to space every hour. What was
creating the atmosphere? The geologically active
surface? Another underground ocean? What was
supplying the heat to generate this obvious planetary
activity so far from the sun? As one project
scientist commented for the news media, for our
exploration of the solar system, "the best was saved for
last." Let's leave our backyard. The distance to Pluto from the Sun is just a speck of space within our galaxy, the distance light travels between breakfast and lunch. Great nebulae such as the Eta Carina nebula abound throughout our galaxy. Astronomers use the word nebula, from the Sanskrit "nabhas" meaning cloud, to refer to both places where stars are born and the remnants of the death throes of a star. Some stars like our Sun die by gas expansion, like sloughing off skin, and become dense white dwarf stars. The death of a larger star is marked by a cataclysmic explosion and is called a supernova.9 The word nova (from the Latin "novus" meaning new) indicates that early observers of the universe thought these objects were new stars. Some stars are so massive -- Mu Cephi is larger than half our entire solar system -- and erupt upon their deaths so violently, that they appear from Earth as if a bright star has emerged from nowhere. The past death of a star in our cosmic neighborhood was absolutely essential to life as we know it, because the basic atomic elements necessary for life are created in the interior of large stars. Without large explosive stars there would be no gold to kindle humankind's greed, iron to build our steel civilization, no carbon to form the basic building blocks of life and to generate our fossil fuels, and no oxygen to breathe. Just as the universe has experienced a structural evolution (the formation of galaxies and gradual expansion of the universe), and at least one form of biological and cultural evolution (on Earth), the universe has also undergone a chemical evolution. During the formative years of the universe only the elements hydrogen and helium existed.10 Over a period of billions of years the nuclear processes that take place in stars have converted hydrogen to heavier elements, and these heavier elements to still heavier elements. When these stars explode they seed the universe with the chemical elements. Our Sun is at least a second-, and perhaps a third-generation star. In our vicinity other stars previously existed. Their violent deaths made our lives possible. |
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Everything around us
is filled with mystery and magic. I find this no
cause for despair, no reason to turn for solace to
esoteric formulae or chariots of gods. On the
contrary, our inability to find easy answers fills
me with a fierce pride in our ambivalent
biology...with a constant sense of wonder and
delight that we should be part of anything so
profound. Lyall Watson, Lifetide Cosmology is the one field in which we can actually witness history. Brian Greene, The Hidden Reality |
Upon their deaths, the most
massive of these stars turn into neutron stars or the
notorious black holes. Neutron stars are supercondensed
worlds where even the atoms have been crushed into a great
ball of neutrons about ten miles in diameter. So
compact are these remnants of an intense gravitational
collapse that a teaspoon of this star stuff would would
weigh several billion tons. On July 3, 2013
astronomers were alerted to an intense gamma-ray
burst. The evidence indicated that two neutron stars
had collided (a kilonova explosion) in a distant galaxy
about four billion light years from Earth. Data from
the Hubble telescope indicated that the explosion probably
created a huge amount of gold, roughly equivalent to about
20 Earth Moons. A black hole is an astronomical
object that stretches our imagination to even greater
limits. It is essentially a hole in our three dimensional
reality, where the future and the past coexist and the
concepts of direction and distance become meaningless. The
mass of a star destined to be a black hole is so large,
and its eventual gravitational collapse so extreme, that
the star's entire material existence disappears into what
mathematicians call a "singularity," a one-dimensional
point. Astrophysicists now believe
that most galaxies have massive black holes at their
centers. The black hole at the center of our Milky
Way galaxy appears to have an equivalent mass of 4 million
suns. Lucky for us that our Earth-Sun system is
about 27,000 light years from the galactic center in a
Goldilocks location in our galaxy for life.
The Crab Nebula is a very famous example of a supernova remnant. In A.D. 1054 the original supernova was recorded by the Chinese, Arabs, and the American Indians. In spite of being over 40,000 trillion miles from Earth, for the first few months it was so bright that a person could read by it at night and it was visible during the day for 23 days. Since the nebula is over 7,000 light years from Earth, what we are looking at now occurred around 5,000 B.C. The explosion is still expanding at a rate of almost a thousand miles per second. Any planet that might have existed within a solar system vicinity (billions of miles) at the time of the initial explosion would have been entirely vaporized. Any planet within a few light years would have been completely sterilized.11 At the center of this explosion is a neutron star spinning around 30 times a second. Astronomers refer to such a spinning neutron star as a pulsar, because we receive very precise pulses of radiation as the star spins its dizzy existence around its axis. So precise and regular is this radiation that when first detected by radio telescopes on Earth, it was thought that we were receiving a message from an intelligent extraterrestrial neighbor. All that we have surveyed thus far, occurs within our galaxy, one galaxy out of billions, another grain of sand. If we were able to leave our galaxy, and travel a few million light years away and look back, astronomers believe we would see something similar to Figure 1-7. This is one of our closest major galactic neighbors, the Andromeda galaxy. It is 2.2 million light years away, a mere 13,200,000,000,000,000,000 miles. What we are seeing now is in a very real sense fossilized light. We are seeing the past, what this galaxy looked like about the same time that our evolutionary ancestor, Homo Erectus, walked through the grass lands of Africa. Spiked points of light visible on the picture frame are stars from our galaxy as we look through it. If this were a picture of our galaxy, our Sun and Earth would be located on the inner edge of one of the outermost visible spiral arms. Our galaxy is a spiral galaxy similar to Andromeda. It is approximately 80 thousand light years in diameter, and even though we are spinning around this galactic merry-go-round at over 500,000 miles per hour, it will take 250 million years to complete one revolution. Some galaxies spin their stars at an even faster rate, over a million miles per hour. For a brief movie that that shows where our Earth is in our galaxy, click here. Just as people and stars are different, so are galaxies. There are dwarf elliptical, giant elliptical, globular, spiral, and irregular galaxies. Figure 1-8 shows the charming Sombrero galaxy. In 1990 astronomers discovered Abell 2029, a galaxy 60 times the size of our galaxy, containing up to 100 trillion stars, and 6 million light years in diameter. If we could travel further out into the universe, looking back we would begin to see clusters of galaxies. The Virgo cluster, a group of over 2,500 galaxies, is about 50 million light years from Earth. It stretches 20 million light years in diameter, and is the closest to what astronomers refer to as the Local Group, the cluster of galaxies in which our galaxy and the Andromeda galaxy are located. |
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A scientist lives with all of reality. There is nothing better. To know reality is to accept it and eventually to love it. George Wald | Still further away we could see a picture
of the Coma cluster (Figure
1-9). With 800 major galaxies, at 500 million light years
from our galaxy, the light that made this photograph left
these galaxies about the time land animals first evolved
on Earth. At 500 to 700 million light years is the Hercules
cluster, 50 million light years across, encompassing
perhaps as many as 5 million galaxies. These clusters are
receding from us at great speeds -- the further away
the greater the speed. The Virgo cluster is receding at
over 700 miles per second, the Coma cluster at over 4,000
miles per second, and the Hercules cluster at over 6,000
miles per second. In general galaxies that are
100 million light years from Earth are moving away at
over 5 million miles per hour. At
twice the distance, galaxies recede twice as fast, and
those at 300 million light-years are moving away at over
16 million miles per hour or over 380 million miles per
day. Quasars
are billions of light years away and recede from us at
speeds of over 100,000 miles per second. They are the
brightest objects in the universe, with the average quasar
being 100,000 times brighter than the Andromeda galaxy.
Most are now thought to be early versions of ordinary
galaxies; their tremendous energy output powered by
centrally located super massive black holes ripping apart
and devouring about ten stars a year. Finally, we see a
map (Figure 1-10) of over a million
galaxies. With new telescopes astronomers now
estimate that there are at least 150 billion galaxies in
the universe, and that this immense outpouring of activity
has been expanding and evolving for about 14 billion
years.12
And this is not all. By the beginning of the 21st
century, many physicists, astronomer, and cosmologists
began to take seriously, based on the best theoretical
attempts to explain the basic features of our universe,
the very real possibility that we live in a multiverse, that our
universe is but a mere bubble in an infinite sea of other
universes. More on this below. |
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A vision of the whole of life! Could any human undertaking be ... more grandiose? This attempt stands without rival as the most audacious enterprise in which the mind of man has ever engaged .... Here is man, surrounded by the vastness of a universe in which he is only a tiny and perhaps insignificant part — and he wants to understand it. William Halverson |
Romancing the Universe
No matter how preoccupied we are with more practical matters on our little planet, every human being must at some time or another confront profound philosophical questions, questions impossible to ask without deeply felt emotion. Why does all this exist? Why are we a part of it? If we are honest with ourselves, is there any philosophy or religion completely consistent with such a perspective? Such an insignificant speck that we occupy, such an enormous extension of time compared to our fleeting existence -- yet we have been able to figure it out. We occupy such a small place, but we are capable of being aware that it is a small place. Imagine a small, intelligent insect in a small isolated forest, that lives for only a few days and whose species is only a few hundred years old, but that nevertheless has been able to indirectly figure out the size and age of the Earth, that it consists of mountains, rivers, continents, oceans, cities and people. Imagine such an insect that has not, and perhaps cannot, travel to these other places, but has expanded its little mind using an indirect process of observation and reasoning to encompass these realities nevertheless. In many ways we are this creature. According to Albert Einstein, this is the greatest cosmological mystery: Not our knowledge of the universe, but why and how do we know it? Today some scientists believe that we are close to knowing the basic details of the origin of the entire universe. What does this mean in terms of who we are? Are there other forms of life capable of this awareness? Are there other kinds of awareness? Does the universe have a purpose? Are we an important part of this purpose? What is the universe for? As we address these questions, we will see that the intellectual evolution of our present understanding is as fascinating as its results. In many ways the meandering path of our understanding is like an enduring but somewhat turbulent romance where each idea is a gesture to the universe for acceptance. Before we can discover anything, we must have an idea of what we are looking for. How we pick the right idea at the right time puzzled Einstein all his life, and much of this book will address this question. But why we seek to understand is no mystery. It is as natural for our species as love. |
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Infinite Textures and
the Microcosmos
Before we address such questions, we must note that our introductory story is only half told. We have only gone in one direction. The size of a printed letter on this page is about 10 billion times smaller than the Earth. Yet, a printed letter is 10 billion times larger than an atom and 100 billion times larger than a neutrino. There is a universe in any direction that we look, an infinite texture to every object. There are insects small enough to fly through window screens of the best kept houses and breed in drains of bathtubs and sinks. To something small enough, the cracks in an egg are like a grand canyon. |
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Nothing is rich but the inexhaustible wealth of nature. She shows us only surfaces, but she is a million fathoms deep. Ralph Waldo Emerson | Usually when we think of insects, we think of them as a rather insignificant part of the life of this planet, at most a nuisance we could do without. Yet, three-fourths of all the species of life on our planet are insects. For every human being there are one million insects. There are 500 species of flea alone, over 3,000 different species of mosquito, and different species of flies and cockroaches have existed for 300 million years. Close ancestors and relatives to the human species began evolving about 3 million years ago. The oldest version of humankind dates to only about 200 thousand years ago. Remarkably, compared to our fragile existence on this planet and that of many mammals, all our sprays, chemicals, and poisons have failed to eliminate a single species of nature's insect inventions. For several decades pineapple growers on the island of Oahu in the state of Hawaii used a chemical called Heptachlor to control ants from ruining the pineapple plants and fruit. The ants are still doing fine as a species, but in the 1980s residents were shocked to find out that almost all of the milk produced on Oahu contained unacceptable levels of this pesticide. After the fruit was harvested, the pineapple plants were chopped up and fed to milk-producing cows, and the pesticide ended up in the milk. | |
The average house accumulates about 40
pounds of dust a year and dust
mites inhabit every house. Over 40,000 of these
creatures could survive in one ounce of mattress dust.
Dust mites feed on the millions of dead skin cells that we
constantly shed. Next, we see a picture of a marijuana
flower (Figure 1-12) and a
spider mite stuck in a broken resin nodule (Figure 1-13). Capturing
insects in its sticky resin is the evolutionary survival
strategy the marijuana plant has adopted to defend itself.
In the State of Hawaii law enforcement officials are
having as much luck eradicating this number one
agricultural cash crop as farmers did eradicating ants.
Perhaps they would have better success if they showed
marijuana smokers electron microscope pictures of what
they are smoking.
Another insect that we have unsuccessfully tried to eliminate with powerful poisons is the termite. It is somewhat fitting, however, that insects have their own insect problems. Figure 1-14 shows a mite on the neck of a termite. If you look very carefully, you can just make out some bacteria in the upper right hand corner. A bacterium is so small (.000039 of an inch long, less than half this distance wide) that a swim across a drop of sweat for one would be roughly the same as having a human being swim across the English Channel. Billions of bacteria make each of our bodies their home, their planet. There are more bacteria on each of our bodies than there are people in the world. Every time we take a hot shower we attempt a little genocide, but within a few hours those that survive will have reproduced to their original numbers. Human beings are even egotistical about their body odor. We think that it is "our" bodies that smell after we have not taken a bath or shower for awhile. Actually, it is the gases emitted from the bacteria that have greatly increased in number. Bacteria have been on this planet for at least 3 1/2 billion years and they are not about to leave. They can survive extremely high temperatures and live deep within the Earth's crust without oxygen or sun-light. |
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Mitochondria seem to
be able to exist, in the form of free-living
bacteria, without our help. But without them, we
die in a matter of seconds. Lyall Watson, Lifetide It is important to realize that life on this planet has spent about three-quarters of its existence in single-celled form, and even today the majority of organisms still exist as single cells. The evolutionary pressure to become complex is evidently not very great. Gerald Feinberg and Robert Shapiro |
From an evolutionary point of view we are
not only surrounded by bacteria, in a sense we are
composed of them! Nine out of 10 of the trillions of cells
that make up the human body are bacterialike cells. All
the cells of our bodies are descendants from the first
bacteria. From this point of view, the human body is thus
just a colony of cooperating animals, and life in general
is not a struggle of the survival of the fittest, but one
of networking, symbiosis, and expanding cooperation.13
Insects and bacteria are huge compared to the
microcosmic spaces routinely discussed by physicists.
Pictured only by the language of mathematics, physicists
are able to investigate spaces called quantum vacuums
filled with "virtual" particles, objects which do not
deserve the name "object" because they both exist and do
not exist. In every material object there is another
universe. All material objects and all life forms
consist of mostly empty space. Material objects consist
of crystals and atoms. All living things consist of
cells, molecules, and atoms. As we will see in Chapter
8, although it is impossible to picture what an atom
looks like and to even think of an atom as a "thing" is
complicated,14
to at least have a vague idea of the relative sizes of
its parts, imagine if we could blow up the size of an
ordinary hydrogen atom to the size of the Earth. The
nucleus of the atom would be about the size of a
basketball located in the center of the Earth, and in
the outermost portion of the Earth's atmosphere we would
find an electron, smaller than a cherry. If the nucleus
was the size of our Sun, then the size of the atom would
be 20 times larger than our solar system, about 70
billion miles in diameter. The nucleus of an atom
represents but a mere trillionth of the atom's volume.
An electron is over 1,000 times smaller in mass than a
proton, a particle that makes up the nucleus of an atom.
Thus, atoms are almost entirely empty space, and
remember, billions of atoms can fit within the space of
a single printed letter. |
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The Cosmic Calendar
If the universe has evolved over a period of approximately 14 billion years, then the Earth and our Sun are relative new arrivals on the cosmic scene, being only about 5 billion years old. Life began on Earth shortly after its formation (4 billion years ago), but complex, multicellular forms of life with bilateral body plans did not begin until about 600 million years ago. Shortly after in geological time, complex life flowered during a period of time geologists call the Cambrian explosion. Some of the first land animals were insect creatures of which the millipedes and centipedes are representative (450 million years ago). We know from the fossil record that some of these first millipedes were up to eight feet long! Some other noteworthy developments were flies and cockroaches (300 million years), the dinosaurs (200 to 60 million years), dolphins (30 million years), the immediate ancestors to the human species (3 million), modern humans (200-100 thousand years), the first technological achievements by humankind (10,000 years), and our modern technological lifestyle from the industrial revolution to the present (200 years). The time scales with which we are familiar in our every day existence are so different from what these numbers represent that it is very difficult to comprehend the significance of such enormous times. To better understand this, scientists make use of an analogy, a cosmic calendar where every second in the calendar corresponds to 475 normal years, a day to over 41 million normal years, and every 24 calendar days is equal to a billion normal years. In this way the entire 14 billion years of cosmic development can be shortened into a single calendar year. Some important dates would look like this: |
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If we are still here to witness the destruction of our planet some five billion years or more hence..., then we will have achieved something so unprecedented in the history of life that we should be willing to sing our swan song with joy. Stephen Jay Gould |
Origin of the universe -- January 1st Origin of our galaxy -- May 1st Origin of our Solar System -- Early September Formation of the Earth -- Middle September Life on Earth -- Late September Sexual Reproduction by microorganisms -- November 1st Oxygen Atmosphere -- December 1st Cambrian Explosion (600 to 500 million years ago when most complex organisms appeared, trilobites, first fish) -- Middle December Land plants and first insects (millipedes) -- December 19, 20 First amphibians -- December 22 First reptiles and trees -- December 23 First dinosaurs -- December 25 Dinosaur extinction, rise of mammals, first birds, flowers -- December 28 First primates (monkey-like creatures) -- December 30 Australopithicenes (Lucy, etc.) -- 10:00 p.m., December 31 Homo Habilis -- 11:00 p.m., December 31 Homo Erectus -- 11:15 p.m., December 31 Early Homo Sapiens---11:53 p.m., December 31 Neandertals -- 11:56 p.m., December 31 Homo Sapiens Sapiens -- 11:56:30 p.m., December 31 Ancient Greeks to present -- last five seconds Average
human
life span -- a
little over one-tenth of a second |
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One tenth of a second! As a child I had the good fortune of being part of a family that enjoyed exploring nature. I can vividly remember one day in particular when an aunt took me on our annual hike in a mountain range of Southern California to what we called the "golden forest." Not far from a small lake was an oasis of very large old oak trees in the midst of mile after mile of pine trees. Every fall the leaves would turn from green to gold, and the startling effect of emerging finally from the green of the pine forest to this magically golden place was well worth what seemed to a little boy a very long walk. On the way back this day we came upon a most beautiful flower. My aunt casually remarked that it bloomed for only a day and then the whole plant died. I remember feeling very sad. I felt so sorry for this poor little flower. Life was so full of freshness and fun for me. It seemed like it would go on for ever, yet this poor flower had only a day to romance the universe. Compared to the age of the universe, each of us is like the flower. | ||
A scientist is ... a
learned child. There is something of the scientist
in every child. Others must outgrow it. Scientists
can stay that way all their lives. George Wald
Sit down before fact as a little child, be prepared to give up every preconceived notion, follow humbly wherever and to whatever abysses nature leads, or you shall be nothing. T.H. Huxley |
Children can be fascinated by almost any
object. Perhaps they feel the universe that each one
contains. Most adults seem to lose the enthusiastic
intensity of exploring ordinary objects. Ironically, an
important condition for being a scientist or a philosopher
is that one not lose a childlike mind, or at least
maintain that curiosity for much of each day. Today,
scientists believe that locked within the physical matter
of every earthly object is a fossil record, a
self-contained, endless detective story that can be traced
back to the origin of our universe. Fueled by a childlike
fascination for our cosmic roots, elegant mathematical
equations, and huge, expensive machinery, astrophysicists
believe we now have a reasonable basis for knowing not
only how our universe began but the details of what
happened within the first fraction of a second, 13.7
billion years ago.
The Multiverse and Inflation The scientifically accepted view today of the origin of the universe is known as the Big Bang theory. At time zero nothing existed but an unimaginably hot, dense point. Not a point "in" space and time; space and time were inside the point! Do not try to imagine this; your mind will not let you create an internal picture of it -- it can only be described mathematically. From this point space, time and energy emerged. At 10-43 seconds,15 what physicists
call the Planck time, the temperature of this energy was
100 thousand billion billion billion degrees. At this
time the separate forces of nature did not exist, such
as the gravitational force which holds us to our
spinning Earth, or the electromagnetic force responsible
for magnetic repulsion and attraction, or what is called
the strong force, responsible for keeping the nucleus of
an atom together, or the weak force responsible for
atomic radiation. At this time, only a single,
unified superforce existed. |
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Unless his mind
soars above his daily pursuits, it is fairly
natural that the working scientist should
characterize his business as a welter of different
techniques. In the same spirit, the woods man
might claim that there are only trees but no
forests. Henry Margenau Amazingly, all the objects we can see with
our telescopes, all these stars and galaxies . . .
are now estimated to make up only about 5% of the
universe. The rest (23% dark matter and 72%
dark energy), the effects of which can be detected,
cannot be seen . . . . many billions of years from
now, the universe will die a cold, lonely death.
There will be no light and no heat anywhere.
The
best available cosmological theory for explaining
the best available cosmological data leads us to
think of ourselves of occupying one of a vast
inflationary system of parallel universes, each of
which harbors its own vast collection of quilted
universes. Cutting-edge
research yields a cosmos in which there are not only
parallel universes, but parallel parallel universes. It suggests that reality
is not only expansive but abundantly expansive. Brian Greene, The Hidden Reality
We
are not only not the center of the universe or
our galaxy; we are not even made of the most
important ingredients of the universe.
|
Don't get lost in the numbers.
Imagine the big picture. On the Fourth of July when
I was a teenager, my cousins and I harassed my
neighborhood with fire crackers. On one Fourth of July
night in particular, I remember that a heavy Southern
California fog unexpectedly aided our mischievous running
from house to house, throwing fire crackers onto people's
porches. At one point one of my cousins ignited a cherry
bomb smuggled from Mexico in the middle of the street, a
sort of grand finale to our night of terrorism. The effect
startled all of us. The misty fog allowed us to see the
extent of the explosion as a yellowish-orange semicircle
with what seemed to be a radius of at least 15 feet. It
probably took only a few seconds for the visual effects to
dissipate, but the unexpected scene caused a slow-motion
picture in my mind. At first the colors were very intense
and expanded quickly, then gradually faded and vanished
over what seemed like a long time. For what was probably
only a fraction of a second, individual speckles of fog
were heated throughout the semicircle, and seemed to flash
with light and life.
The bottom line is that we are living in the midst of an explosion, luckily in a relatively mild, somewhat frozen, period. We can measure the current temperature of this explosion by detecting a faint radio whisper with our radio telescopes, confirm the existence inflation and the initial quantum ripples with satellites in orbit around the Earth, view the Universe backwards 13 billion years with our optical telescopes, and now use the light from supernovas to detect the accelerating effects of dark energy.16 In the cherry bomb example, imagine our surprise if
instead of the dissipation and the spreading speckles of
fog gradually slowing down, if about half way through
the expanding explosion, the spreading accelerated, like
throwing a ball up and watching it slow gradually in its
ascent but instead of stopping at a certain height and
coming back down, at a certain point the ball then
zoomed away into the sky. We believe now that
most likely the expansion of the universe will go on
forever, due to the mysterious force of dark
energy. Amazingly, all the objects we can see with
our telescopes, all these stars and galaxies, all the
basic stuff for making planets, plants, and animal
bodies, are now estimated to make up only about 5% of
the universe. We are not only not the center of
the universe or our galaxy; we are not even made of the
most important ingredients. The rest (23% dark
matter and 72% dark energy), the effects of which can be
detected, cannot be seen. So, eventually from any
point in space no galaxies or stars would be visible.
Finally, many billions of years from now, the universe
will die a cold, lonely death. There will be no light
and no heat anywhere. . . . the
pattern is clear. When we hand over the steering
wheel to the mathematical underpinnings of the major
proposed physical laws, we've driven time and again
to some version of parallel worlds. For instance,
one of the most worked on and hopeful new theories
is called string theory, where the point-particle
picture of subatomic objects is replaced with a
geometry of vibrating strings of energy moving in
hidden multidimensional spaces. But in examining the
geometry of the multidimensional spaces, one
discovers that the one (not yet known) that may
produce our universe and its particular
characteristics -- the
particle parameters, the strength of the
gravitational and inflationary forces, and rate of
cosmic expansion -- may be
caused by just one multidimensional special
geometric twisting, turning, and enfolding out of 10500 possibilities! This shocking development has one major virtue. It
explains why our universe has specific features.
As Greene notes in his book, if you walked into a shoe
store in a large city, you would be shocked if the only
shoes available were your exact size. Baffled by
the amazing coincidence your mind would long for an
explanation. On the other hand, no explanation is needed
when you find your shoe size in a normal store that
carries a wide variety of sizes. So if our universe is
only one of many, possibly an infinite many, we know at
least one out of this huge set of universes would be our
universe with the particular parameters that we have
discovered. We no longer need an explanation. However,
this also may mean that our universe is one of a few,
perhaps the only one, in which life can evolve. It all sounds like a grand made up myth. We have
discovered, however, that the truth is much more
fantastic than our most imaginative myths. It is also
very serious business with billions of dollars spent
each year by competing countries and teams of scientists
to unravel the smallest details of nature's secrets,
especially as to what occurred in the first fraction of
a second 14 billion years ago. The European Council for
Nuclear Research (CERN) near
Geneva, Switzerland, is a place were childlike
fascinations with ordinary objects are expressed in
grown-up serious form. This physics laboratory is the
size of a small city, cost billions of dollars, and has
a staff of over 3,000. Here 2,000 physicists play with
the microcosmos.
About 100 of these scientists are a special breed.
Their colleagues call them theorists. These men and
women may be some of the happiest people in the world.
They get paid fairly good salaries to spend their waking
moments doing nothing but mathematical speculation and
deduction. For many it is a passionate obsession that
never ends. Formally, their work is done with complex
supercomputers, but it is often also done on the back of
cocktail napkins, and in their dreams. For students
struggling to get through their first algebra class, it
is probably very difficult to imagine that such activity
can be meaningful and fun. But for these men and women,
following an ancient tradition that began with the
Greeks, mathematics is the key to unveiling the secrets
of the universe, and they dream of Nobel Prizes and
some, following another tradition popular in the
sixteenth and seventeenth centuries, of being the first
to read the mathematical mind of God. Although the United States had the Tevatron collider at Fermilab, in Illinois (shut down in 2011), a Relativistic Heavy Ion Collider (RHIC) at Brookhaven in New York, and the Stanford Linear Collider in California, it is worth noting that in the 1980s American physicists proposed, and the government began to fund, a Superconducting Super Collider. At a cost of $11 billion, it was nicknamed the Desertron, because it was planned to be so big it would need to be built in a desert. At a circumference of 54 miles, construction began in Warahachie, Texas. After spending $2 billion and the construction of huge underground tunnels, the project was canceled by a budget-cutting Congress in 1993. The Super Collider purportedly would have been able to mimic experimentally the conditions of the early universe to within a thousand of a millionth of a millionth of a second from time zero. |
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The Relevance of the
Cosmic Perspective
Is the spending of billions of dollars to know what happened at the beginning of the universe 14 billion years ago evidence of our unique intelligence or our madness? Do we really need to know what happened when the universe was only a trillionth of a second old and whether or not the multiverse is real? Why spend billions of dollars on space exploration and massive machines to find out what matter does under conditions similar to the first stages of the universe when we have so many urgent immediate problems. Poverty and environmental sustainability problems are overwhelming. Global warming is real and evidence exists that it will increase violent clashes over resources. We still have enough nuclear weapons to destroy the world many times over. Ethnic conflicts and terrorists attacks proliferate around the globe and military scientists study how to make biological and robotic weapons. Should not our more immediate concerns be primarily social, economic, and political? The answer to this question is very long. In fact this entire book is an answer to this question. In the end we will argue that the ancient Greek philosophers were right: A rational connection exits, though not a purely logical one, between knowledge and the good life, both on the individual level and the social and political as well. We will show that an understanding of our cosmological, biological, cultural and philosophical roots is a necessary condition for understanding ourselves and making crucial choices affecting the future of the human race. The human species is at a crucial crossroad, and understanding our cosmic setting is a critical variable in our struggle for survival. |
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Our intelligence has brought us far, but it has also brought us to the brink of total destruction. It cuts both ways, its application sometimes terrifies us, but it also reveals a humbling, sobering perspective of our cosmological home. |
Although we are most interested in
philosophical considerations, we can briefly discuss a few
preliminary points. First of all, there is a well known technological
spin-off from adopting a cosmic perspective. Studies
have shown that for every dollar we spend on exploring
space, many dollars are returned to the economy in terms
of revolutionary products and economic development.18 To
name only a few, the space program has given us Teflon,
Velcro, integrated circuits, miniature computer chips and
advanced microprocessors, satellites, solar energy,
revolutionary medical technology, and probably some day
space manufacturing and industrial parks in orbit around
the Earth. Among other things that could be made more
efficiently because of microgravity and the superior
vacuums attainable in space, these industrial parks will
manufacture medicines that would cost millions of dollars
per pound if manufactured on Earth; amounts that would
take 30 years on Earth would take only 30 days in space.
Millions of dollars are now invested annually in remote
satellite sensing of the Earth's surface to map mineral
deposits, vegetation patterns, and land use. The ancient Greeks believed that all knowledge was interrelated and valuable. Some people are often cynically amused upon reading that someone has just received a PhD for studying what happens to drops of water when they strike the surface of a pool. Those with the appropriate scientific background know, however, that such research has applications for the design and analysis of turbines, cooling towers, steam generators in nuclear reactors, and many chemical processes. Or, we might find many nonscientists laughing and shaking their heads when they pick up the newspaper and find that there is an international meeting of scientists, sponsored by the American Association for the Advancement of Science, on "The Biodiversity in Mud and Dirt." But little do these people realize that subsurface creatures (bacteria, fungi, mites, earth-worms, and one-celled organisms) provide the balance of essential elements (carbon, nitrogen, phosphorus) and distribute water and remove wastes, activities without which above ground life (plants, animals, and humans) could not live. Furthermore, many people will roll their eyes at any discussion of Einstein's general theory of relativity, wondering why any one should care about black holes, the origin of the universe, the slowing of time, and warped space. Yet, they will happily use and depend on their GPS navigation systems in their cars and smartphones produced in large part by applying Einstein's theory. |
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We need people who
can see straight ahead and deep into the problems.
Those are the experts. But we also need peripheral
vision and experts are generally not very good
at providing peripheral vision. Alvin Toffler Man differs from the animal only a little; most men throw that little away. Confucius |
The exploration of space has also given us
an environmental spin-off. The more we have
studied our astronomical neighbors, the more we have
learned about our Earth. By studying Venus we have been
alerted to the climatic danger of global warming and a
runaway greenhouse effect. Because of the dense atmosphere
of the planet, radio mapping was developed to visualize
the surface. This technology is now applied to finding
mineral resources on Earth and ocean mapping for a better
understanding of continental drift. Studying Mars has led
to a better understanding of volcanism, weathering, and
chemistry. The Voyager flights by Saturn, Jupiter,
and Uranus, the Galileo
flight to Jupiter, and the Cassini-Huygens to
Saturn, have taught us more about electromagnetic
fields, different types of weather, and by studying the
moons of these planets, we have learned more about the
varieties of planetary geology.
The telescopes on Mauna Kea, noted at the beginning of this chapter, not only can peer backwards in time to see galaxies 13 billion years old and study black holes, including one in the center of our galaxy. Some of these telescopes can detect asteroids that could threaten our planet and some can scan the Sun and warn us of magnetic storms that fry our satellites' electronics and cause massive power outages on Earth. By 2004 astronomical activity contributed $150 million to the State of Hawaii in economic and technological development and produced 600 jobs. Most important for the focus of this book, however, is what we will call philosophical and psychological spin-off. That human beings have progressed materially is not doubted by even the most severe critics of science and technology. Questioned is whether a scientific approach to life has made us better as individuals and as a society. Do new technological feats benefit the poor or only the rich? Have human beings made significant moral progress or have the tools of manipulation, exploitation, and control just become more sophisticated? Is our potential for awareness, of "figuring things out," an asset, or an evolutionary mistake, a dead end? Does scientific knowledge make life simpler or dangerously more complicated? Is the technological-scientific culture that is sweeping the globe just another form of cultural imperialism? Is scientific objectivity actually a grand myth and science only a male-oriented interface with nature; only one of many possible interfaces, and a rather unhealthy one at that based on dominance and exploitation? |
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The dangers that
face the world can, every one of them, be traced
back to science. The salvations that may save the
world will, every one of them, be traced back to
science. Isaac Asimov Humans everywhere share the same goals when the context is large enough. And the study of the Cosmos provides the largest possible context . . . . If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another . . . . If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth. Carl Sagan, Cosmos "We
are
hit by tons of material every day, but it is all
dust. We are all walking around with comet dust
in our hair." Don Yeomans
"The
city is a place where people always seem bitter
with each other . . . (but the meteor) was one
of the rare times when people started to live
together through one event." Chelyabinsk
music teacher Ilya Shibanov
That our Earth appears calm and
secure from cataclysmic outside forces is a
temporal illusion.
Because we are living at a relatively
mellow time cosmologically and geologically, the
majority of the people on our planet ignore, forget,
or are ignorant of our true cosmic setting . . . we
fail to realize our common interest as all citizens
of a very fragile, temporary little piece of
paradise. |
The response to these charges is that the
present scientific revolution will not change human
nature, nor would it be desirable to do so. Animal species
are biologically programmed to be self-centered under
certain conditions, and the human species is no exception.
Giving selfish creatures more knowledge could well be very
dangerous. However, the essential claim is this: the
potential for positive change rests in that an awareness
of our true cosmic setting should make a substantial
contribution for making a better planet by refocusing our
natural concern for individual survival and making more
human beings aware of their true self-interest as part of
an endangered family on a fragile little planet surrounded
by a hostile environment. In other words, when confronted
by a common problem, an outside force or threat, it is a
well-known historical and psychological fact that human
beings are capable of great cooperation, of unique
altruistic acts, of seeing apparent major differences as
confining illusion. The cosmic perspective is like a slap
in the face that reminds us to wake up and remember that
we are all in the same boat. Awareness is needed on the
part of a critical mass of people for a triple bottom line
-- people,
planet, profit. Personal success and support for those we
care about most cannot be separated from social and global
concerns and the ecological health of the planet. The scientist who made this argument the clearest was the late Carl Sagan. He argued that the worldview of modern science that you have learned in this chapter was not just "nice to know stuff." Nor was it just for purely practical purposes of creating better technology. He argued that this knowledge was essential to the survival and moral improvement of the human race. An old Humphrey Bogart movie illustrates the essential point. In The Treasure of Sierra Madre, Bogart plays a man down on his luck who eventually links up with a couple of similarly inclined cohorts who just happen to finally strike it rich prospecting for gold in the dry foothills of Mexico's Sierra Madre mountain range. By finding so much gold they then have to worry about how to keep their claim protected and how to move the gold and turn it into cash without revealing their secret. They also become challenged by a feverish greed that begins to envelope each of them. Their cooperation becomes tenuous and their suspicions of each other intensify as the gold and their potential wealth accumulate. One day one of the men must make the dangerous journey to the nearest town for supplies. Being an ethnic stranger in a Mexican town, he will obviously attract attention. There are bandits everywhere and it would be easy for someone to follow him back to their gold. Ironically, his biggest problem when he gets to town is that another U.S. citizen is already there. This man naturally expects a reaction of companionship, and is surprised by the partner's aloofness. The partner hurriedly gets his supplies and leaves town, and in spite of his attempts to avoid being followed, the stranger manages to find their camp. The stranger was interested in the companionship of someone of his own culture in a distant lonely land and a little gold, but he knows his life is at stake. He pleads with the three men to take him in as a partner. There is plenty of gold for all, and an extra gun could be handy in this unfriendly place. A decision has to be made. The stranger is disarmed and the original partners withdraw to discuss the situation. They decide that they have three alternatives. They can persuade him to leave and not tell anyone of their find in return for not killing him; they can take him in as a fourth partner; or, they can kill him. For a brief moment they look at each other and then without any further discussion one partner asks, "Who's going to do it?" It is a drastic move. None of them has ever killed a person before, but they have become desperate, selfish men. The matter is settled by concluding that they should all shoot him at the same time. They return to the edge of a cliff where the stranger has been awaiting their decision. All that needs to be done is to shoot him and push him over the edge. "Well..?", he asks. The men pull their guns. The stranger shows little surprise, not an unexpected decision, another disastrous event in a string of bad luck. At the last minute, however, the stranger turns to look down the cliff and calmly remarks, "Before you pull the trigger, you better look down there." The men see a large cloud of dust far down the mountain and soon the cause is clear. Coming up the mountain on horse back, riding at a furious pace, is a large group of bandits. Fear instantly registers on the faces of the men. Without saying a word, a gun that a moment ago was to be used to kill the stranger is uncocked and tossed to him; the four men get ready to defend themselves. They were enemies, but now there is much larger outside threat. The four men are able to ambush the bandits, and after a furious gun battle, force them to retreat by inflicting heavy casualties. On their side, only the stranger is killed. Before they bury him they find a letter from his wife. They discover that he was just like them. A man down on his luck, looking for some way to strike it rich so he could return to his wife and children. Our situation as a species today is quite similar. In many ways we are surrounded by cosmological bandits and monstrous outside threats. From a cosmic perspective our differences, trumpeted daily on the front pages of our newspapers, vanish in the face of our cosmic setting and what should be our true self-interest. A cosmic perspective reveals an awesome cosmic predicament. We occupy a very small space and have lived a very small time. Our cosmic home is a place where monstrous violent physical processes are the norm. It would not take much for our little fragment of the universe to undergo drastic change and we, and all our accomplishments, would be gone. A star close to us could become a supernova and fry the Earth with radiation. As our little star circles our galaxy, another star could pass close to our solar system, disturbing what astronomers call the Oort cloud, a swarm of trillions of comets which orbit our Sun beyond the orbit of Pluto. Some of these comets would be pushed into our solar system and debris could then strike the Earth, causing death and mass animal extinctions -- a process that some scientists believe is a relatively normal periodic process, and the cause of the extinction of the dinosaurs. Much closer to Earth, past the orbit of Neptune, is
another swarm of perhaps up to a billion comets called
the Kuiper Belt. Closer still is the asteroid belt
between the orbits of Mars and Jupiter. Most
importantly, there are an estimated 20,000 asteroids
that are classified as "near-Earth" that range in size
between 330 feet and six miles wide. Any hits from these
asteroids would cause tremendous destruction on Earth.
The smaller ones could destroy a city. A hit by one of
the larger ones, the size of a mountain or larger, would
have global consequences. The comet that caused the
dinosaur extinction was believed to be a little over 6
miles in diameter. The asteroid 433
Eros is over two times larger (13.2 miles in
diameter), and it is predicted by some astronomers to be
gradually pulled by its gravitational interaction with
Mars into an "Earth-crossing" orbit, possibly
intercepting the Earth within a million years.19 A
million years may not be much to worry about, and
although our knowledge of near-Earth asteroids is much
better today due to NASA's Near Earth
Object Program, there are still many asteroids and
comets that we do not know about. The asteroid 4179
Toutatis was not discovered until 1989 and in
November 1996 it zoomed across the night sky a mere 3
million miles from Earth. By 2004 Toutatis missed the
Earth by only a little over 950 thousand miles. In
January 2002 an asteroid large enough to destroy France
or Texas hurtled past the Earth at a distance of only
500,000 miles, only twice the distance to the Earth's
moon. Called 2001 YB5, it was not discovered by
astronomers until late December 2001. At 1,000
feet across and traveling at 68,000 miles per hour,
there would have been no time to protect the Earth. In
2011 the asteroid YU55 came within 202,000 miles of
Earth, a distance inside the Moon's orbit, and close
enough for the gravity of the Earth to change the
asteroid's orbit. At about 1300 feet in diameter, the
asteroid would have generated a 70-foot-high tsunami if
it plunged into one of our oceans. In February
2013, asteroid 2012 DA14, about 150 feet long, passed
17,150 miles from Earth. It was not discovered
until 2012. At the same time, and completely
unpredicted, a meteor about 55 feet long and weighing an
estimated 7,000 tons slammed into Earth's atmosphere and
exploded 20-30 miles above the Earth's surface over
western Siberia. About 1200 people were injured as
a result of the shock wave from flying glass (about
4,000 windows were blown out) and other debris in and
around the city of Chelyabinsk, a city traditionally
used for Russian defense factories and nuclear weapons
production. At this time the city of Chelyabinsk
was Russia's main nuclear waste disposal facility and a
large plant for disposing chemical weapons was located
50 miles east of the city. A 500 kiloton energy
shock wave blast was generated, equivalent to 20-30
nuclear bombs. The meteor entered the Earth's
atmosphere at a shallow angle, otherwise with a more
direct hit the blast could have destroyed a city the
size of Chicago. About 200 days a year on average,
a 30 foot long asteroid passes by the Earth inside the
orbit of the Moon. These asteroids are part of an
estimated 50 million undiscovered and unplotted
"near-Earth" objects. Although by 2011 NASA surveys of the number of near-Earth asteroids and their orbits indicated less hazard than previously believed, given enough time, enough cosmic debris, and gravity, like strangers in the night our Earth and some of this debris will meet in the future. Some astronomers estimate that a large destructive comet strikes Jupiter about once every 400 years and the Earth every 13 million years.20 The Chelyabinsk meteor was described as a once-in-every-one-hundred-years event. That our Earth appears calm and secure from cataclysmic outside forces is a temporal illusion. If these time frames seem too remote, consider that even on Earth we live within a relatively small fragile slice of biological heaven. Below us are massive amounts of molten rock -- 99.9 percent of our Earth is an inhospitable hell. More often than we would like this fiery hell comes to the surface in the form of volcanic destruction. Here too we may be living at a relatively quiet time. Some scientists believe that massive past volcanic eruptions produced major extinction disruptions on Earth. Above us is a relatively thin blanket of protective ozone shielding us from deadly ultraviolet rays from the Sun and left over radiation from supernovas. If your body could be magically transported to Mars, you would die of an agonizing sunburn much before you would freeze to death; there is no ozone layer on Mars. Within this protective belt on Earth all our infrastructure that seems so durable and impressive resides on relatively thin shells of moving plates that crash into each other causing earthquakes and massive tidal waves. Consider that one hundred thousand years from now Los Angeles will be next to San Francisco, because Los Angeles is on a plate sliding toward San Francisco. Both cities will be destroyed long before this happens. Some day half of the large volcano called Kilauea on the island of Hawaii will fall into the ocean, causing a tidal wave (tsunamis) about 1,000 feet high. The tidal wave will destroy the city of Honolulu within minutes and race across the pacific at 600 miles per hour and devastate cities in Japan, California, and Australia.21 Because we are living at a relatively mellow time cosmologically and geologically, the majority of the people on our planet ignore, forget, or are ignorant of our true cosmic setting. And like the men in the Bogart film, we fail to realize our common interest as all citizens of a very fragile, temporary little piece of paradise. We destroy parts of our ozone protection in pursuit of short-term business gain, and think that some things on Earth are so important that they are worth killing each other over. Philosophers use the word contingent to refer to the fact that our existence is dependent upon events that we have no control over. The world view of modern science that we are examining shows us to be contingent beings with an historically contingent past. No plan for the special production of the human species is apparent. Many events had to be just right or we would not be here, and there is no special guarantee for the future of our species. Less technically, the world view of modern science shows us to be very, very lucky. Some people are shocked by the apparent meaninglessness of this view of life. You mean the universe was doing billions of things before we got here and it did not wait until we could take center stage? You mean the universe is going about its business without special regard to our safety and happiness, and that in an instant it could crush us like an insect? However, one can also find exhilaration and resolve in this view. We have been able to figure it out, and we are not only very lucky, we are very, very precious. The right conditions that produced the human species will never be repeated again. |
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In the nature of life and in the principles of evolution we have had our answer. Of men elsewhere, and beyond, there will be none, forever. Loren Eiseley, The Immense Journey |
Understanding our biological roots and the
law of natural selection, the mechanism of evolution
discussed in Chapter 3, demonstrate that life may exist
elsewhere, but it will not be like us. An artist once
complained to me that in a single human face there is an
infinite texture and beauty, and that there is no need to
study the universe of the astronomer. The appropriate
answer to him is that by exploring the cosmic perspective
and the awesomeness of our physical situation, we can more
readily appreciate the uniqueness and beauty of a single
human face. We have discovered, according to Loren Eiseley
in his book Immense Journey, that "in the nature
of life and in the principles of evolution we have had our
answer. Of men elsewhere, and beyond, there will be none,
forever."22
Nowhere else in the billions of galaxies will there evolve
again human beings to share our loneliness.
Our cosmological calendar in this chapter is very misleading in one sense. It implies that the 14 billion year history of the universe has had but one purpose: the linear, progressive evolution of the human species. Yet the list of events on our calendar is only one possible list that could be displayed showing a particular species at the end. The cosmic calendar is not a list of progressive success. For instance, modern humans did not evolve from less intelligent, more brutal Neandertals. Neandertals were just as intelligent, just as compassionate, and existed at the same time as early humans. They had their day in the sun so to speak. They are gone, but our species will need to survive another 200,000 years to match their longevity. An understanding of natural selection and evolutionary biology, the science that fills in the details of natural selection on Earth, demonstrate that even on Earth we are not special. No species is special. The majority of life forms that have lived on this planet are extinct, and the average life time of a species is 10 million years and a vertebrate species like ourselves a mere 2-3 million years. A study of biological evolution is a sobering and humbling experience, revealing no apparent direction or purpose. Life evolves, not with a design in mind or lofty plans for the development of a ruling creature, but by offering variety, spinning the wheel of chance with every birth, gesturing with each unique creature for acceptance from the environment. In the process it produces a "messy" equality, a very wide bush of successful branches with no branch any more fit than another or guaranteed a long future. Human beings are doing well in terms of sheer survival numbers, but insects are also doing very well, and they have been here much longer and are much more likely to survive a human-made or natural catastrophe. As humans, we boast and celebrate that we alone possess "intelligence," but even if this is true, there is no guarantee from nature that this characteristic is any better than the body structure of a mosquito; it is just another experiment, another gesture for acceptance, perhaps only an evolutionary afterthought. All we can honestly say is that both the characteristics possessed by human beings and mosquitoes have served each well, so far. |
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We need another, wiser, and perhaps a more mystical concept of animals. For the animal shall not be measured by man....They are not underlings. They are other nations, caught with ourselves in the net of life and time, fellow prisoners of the splendor and travail of Earth. Henry Beston. |
Cosmic Brethren We are all related. We are all cousins, floating together on this fragile blue biological refuge. No supremacy exists amongst biological brethren, only creatures adapted to their environments for the moment. What evolutionary biologists call the fossil record is sobering in this respect. The trilobite, an animal that flourished for over 150 million years in the ancient seas, some 400 million years ago, is now extinct; it demonstrates that although life has thrived on Earth for a very long time, adaptability is temporary and does not insure future success. The trilobite is an example of a radical invention that took place in these ancients seas, the shell. It also shows that complexity and sophistication are not the inevitable products of better, more modern times or "higher" creatures. The eyes of one species of trilobite consisted of 15,000 separate lenses. Its closest living relative is the less sophisticated horseshoe crab. The fossil record also shows transitions between life and death. Archaeopteryx, or "ancient bird," shows transitional features between those of the dinosaurs and birds. A bird's feather is made of the same material as that of a reptile's scales (so are our finger nails!), but more striking is that in archaeopteryx we see examples of a reptile claw and tail. Most evolutionary biologists today have concluded that this creature was not a true bird. Because of its body structure, its wings would have been very weak, and it was probably just a glider.23 |
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There is no such thing as a destiny of the human race. There is a choice of destinies. J.B.S. Haldane | When most people in the developed world
think of a bird, they probably think of a little
sparrow-like creature. The cassowary
of New Guinea, which can be as tall as a small person
and be very dangerous, still exists today. It is an
example of a similar evolutionary strategy as that of
diatryma, a huge flightless bird that was over 6 feet tall
and lived 65 million years ago. Because flight requires
the expenditure of a great deal of energy and consequent
food gathering, if there are no predators, birds will
sometimes evolve in the direction of losing the
characteristic of flight and increase in size. Because
nature has no absolute preference for any particular
survival strategy, sometimes losing what seems like a very
valuable survival trait actually has survival value. The
modern Ostrich is example. Recently, paleontologists and
anthropologists discovered what may be an extinct dwarf
relative of the human species. Named
Homo floresiensis, or Flores Man,
because its bones were found on the remote Indonesian
island of Flores, these hobbit-sized creatures were only
about three feet tall. The species became extinct
about 50,000 years ago, probably when a massive volcanic
eruption wiped out the entire species.
Just as birds tend to lose the ability to fly and
increase in size if food is plentiful, nature shows that
animals -- deer, squirrels, pigs, and elephants for
example -- that live in marginal, isolated environments
gradually dwarf when food is not plentiful and predators
are not threatening. Although
whether or not Flores Man is an example of "island
dwarfing" is controversial, as we will see in Chapter 3,
no physical characteristic is inherently good for
survival from an evolutionary perspective. Some of the
first millipedes had life on land mostly to themselves
and some remember were eight feet long. Today,
with a lot more competition, most are less than an inch
and the largest about eight inches.
Moles are another example of nature's evolutionary flexibility. Many species have very reduced eyesight; some are blind. Instead they have sense organs at each end of their bodies, large hands, and powerful forelegs for a life spent predominantly underground, digging tunnels and harvesting worms that fall into the tunnels. Moles are also an example of another evolutionary revolution, the mammal. When the dinosaurs became extinct about 65 million years ago, the mammals developed in many directions. They now come in many shapes and sizes, possessing various survival strategies. The variety of our brethren is endless. Variety is nature's way of making sure something works. Many species of anglerfish flourish in the seas, some at great depths. All possess little fishing poles, fleshy appendages that grow from the tops of their heads, with which to entice a dinner close to their mouths. The pink flower mantis looks exactly like a beautiful flower, which is very convenient when you eat insects that are attracted to such colorful displays. The echidna is a mammal that looks like a ball of spikes. With powerful claws, this spiny anteater can dig into the hardest ground in seconds for protection. The tamandua is a tree anteater; it looks like a big dog with a very long nose. The long-eared bat uses sonar to experience the world. It sends out clicks 20-30 times a second and can navigate quickly around objects at night, a navigational feat that no human machine could dare mimic. The tarsier, which still lives in the forests of Southeast Asia, is an example of early mammal development. Like most early mammals it is nocturnal and has developed large eyes to gather light at night. It looks like a strange little bear with funny suction-like feet for grasping the tree branches in which it lives, and its eyes are so large that they are fixed in their sockets. To overcome this disadvantage, it can swivel its head 180 degrees and look directly backward without turning its body. |
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Not understanding our true setting and our evolutionary past is as dangerous as ignoring the law of gravity. |
All mammals, including the human species,
evolved from a common ancestor, a rat-like nocturnal
creature, similar to the modern tree shrew. Like the
modern tree shrew, this mammalian ancestor was probably a
tough little guy that had to be very careful. The daytime
world was dominated by dinosaurs that reached heights of a
six story building, and the recently discovered
superdinosaur, Seismosaurus (120 feet long and weighing
100 tons). Although hyperactive and jittery and smaller
than a mouse, a modern shrew can kill a large rat.
In spite of this ancestry, not all mammals are fierce and jittery. The sloth, which resembles a huge, elongated dog with long, spiked claws, reveals an evolutionary development that parallels the loss of flight in some birds. Because of a nonthreatening environment, this creature has not only lost its ancestral nervousness, but lives as if in a slow motion time warp. The less an animal moves, the less it has to eat -- just another survival strategy. The sloth has a top speed of half a mile an hour, sleeps 18 hours per day, and has a disgusting hygiene -- algae, moths, and even caterpillars make its fur their home. It even defecates and urinates only once a week. As obnoxious as this creature may be to us, it displays the same revolutionary reproductive strategy common to all mammals: love and care for their young. The attraction to our babies is part of our mammalian heritage. This ability to relate positively to a youngish appearance may well account for the popularity of the five inch tall pygmy marmoset monkeys at zoos, puppies, and even, according to the late Harvard naturalist, Stephen Jay Gould, the progressively more childish appearance of the cartoon character Mickey Mouse over the years. |
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Life has found ways to flourish in boiling hot springs and on icy mountain tops, to fly, glow in the dark, put forth leaves in a rainless desert, or plumb the ocean, reproducing and adapting, reincarnating itself in new forms in defiance of time and death. Douglas H. Chadwick | Evolution not only diverges into
greater and greater diversity. It also converges.
A characteristic which has superior survival value,
relative to the general environment on Earth, can evolve
in creatures that are not very closely related. Birds and
insects are not very closely related, but they both fly.
In Hawaii there is a hummingbird
moth that resembles a hummingbird and even gets its
food in a similar manner, feeding on the nectar of flowers
while hovering like a helicopter. In South America there
are frogs that use the enlarged webbing in their feet to
glide from tree to tree, recalling the flying squirrels of North
America and Australia.
An awareness of the endless variety and temporary adaptability of life on Earth is crucial for our times. Much of Western human history has been dominated by a philosophical and religious outlook that has repeatedly granted a central status to human nature and questionably professed a special dominion for humankind over the Earth and its resources. Not understanding our true setting and our evolutionary past is as dangerous as ignoring the law of gravity. |
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To understand [our cosmological roots]...is to give voice to the silent stars. Stand under the stars and say what you like to them. Praise them or blame them, question them, pray to them, wish upon them. The universe will not answer. But it will have spoken. Timothy Ferris |
During the cold war era, the leaders of the
former Soviet Union and the United States thought it wise
to have 300 billion dollar per year defense budgets, but
unwise to spend a mere 10 million dollars per year on a
Spaceguard program proposed by scientists to survey space
for the locations of near-Earth and Earth-crossing
asteroids. For the United States, a single B-2 bomber
required $2.2 billion per plane. During the initial
stages of the 2001 bombing in Afghanistan, the United
States spent $1 billion a month with a $5,000 per hour
cost for flying a Navy FA-18 fighter and $1 million for
each Tomahawk cruise missile. In Iraq, at various
times the military cost approached $2 billion a
month. The total cost of both the Afghan and Iraq
wars, including economic disruption and long term medical
support for veterans, may be as high as $3.7 trillion.
Today, the vast number of ethnic conflicts around the globe, the debate over who is a terrorist and who is a freedom fighter, genetic engineering, cloning, and self-replicating biological and robotic weapons are just some of the major concerns that have replaced the fear of nuclear Armageddon. Investing some time in understanding our true cosmic setting is not only practical in the immediate sense of avoiding tragic mistakes founded on ignorance,24 but supplies the philosophical setting for a more unified planet as well. Our existence on this planet is the
result of a meandering path of serendipity. We now have
much power. The same knowledge that allows us to
genetically engineer plants to produce a new polymer in
their leaves and seeds for a biodegradable plastic, also
allows us to potentially engineer viral weapons that
would target specific ethnicities. What we do with this
power will depend on our values. What values we ought to
have will depend crucially on understanding the big
picture and what Sagan called the cosmic perspective. As he summarized in his 1994
Pale Blue Dot: A
Vision of the Human Future in Space, "The Earth is a very small stage in
a vast cosmic arena. Think of the rivers of blood
spilled by all those generals and emperors, so that,
in glory and triumph, they could become the momentary
masters of a fraction of a dot. Think of the endless
cruelties visited by the inhabitants of one corner of
this pixel on the
scarcely distinguishable inhabitants of some other
corner, how frequent their misunderstandings, how
eager they are to kill one another, how fervent their
hatreds. Our posturings, our imagined self-importance,
the delusion that we have some privileged position in
the universe, are challenged by this point of pale
light." |
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| | | copyright 2001, 2004, 2011 Ronald C. Pine |
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Notes:
1. We will use miles rather than kilometers. To convert the number of miles to kilometers multiply the number of miles by 1.62. Thus 66,000 miles per hour x 1.62 = 106,920 kilometers per hour. Click the Back button to return to text.
2. As we will see in Chapter 7, "Understanding the Theory of Relativity," there are no stable (absolute) spatial mathematical points. Thus, there is no such thing as the same place.
3. As we will see in Chapter 8, "Quantum Physics and Reality," it is a mistake to think of particles of light as ordinary objects that have a small, but localized, size. For now consider that billions of atoms make up the head of a pin, and that an atom is over 1,000 times more massive than a photon.
4. The Sun, however, is gradually expanding. In about a billion years it will have expanded enough to cause a massive greenhouse effect on Earth and our oceans will boil away. It is unlikely that life as we know it will exist on Earth at this time.
5. According to a report from the Jet Propulsion Laboratory, "Prospects for the Voyager Extra-Planetary and Interstellar Mission," Journal of the British Interplanetary Society, March 1984, Pioneer will then make a "remote" flyby (it will still be 19 trillion miles away) of the star Ross 248.
6. Astronomers also use the measurement known as a parsec (3.26 light years). Thus, the distance to the Eta Carina Nebula is 2,800 parsecs, or over 9,000 light years (54,000,000,000,000,000 miles).
7. Deep biologist Thomas Gould of Cornell University has proposed that if we added up all the biomass living below the Earth it would equal or surpass that living above.
8. At the time of the Voyager and Galileo flights, because of its eccentric orbit, Pluto was closer to the Sun than Neptune until 1999.
9. Astrophysicists believe that for a star to be a supernova it must be at least a dozen or more times as massive as our Sun. In 1987 a supernova was observed in the Large Magellanic Cloud, a relatively small satellite galaxy of stars to our own galaxy. The original star, previously observed and cataloged, is estimated to have been 15 times more massive than our Sun.
10. Next time you have a glass of water or take a swim or a bath, consider that the hydrogen atoms in the water were formed within the half million or so years of the existence of the universe, some 14 billion years ago.
11. The supergiant star Betelgeuse is about 540 light years from Earth, and it is so large that if it could be magically transported to the location of our Sun, it would extend to the orbit of Jupiter, approximately a billion miles in diameter. If such a star exploded today, it might cause harmful radiation to strike the Earth 500 years from now. There have been five major extinction events that we know of for Earth's history. The extinction event 440 million years ago killed two-thirds of all species living at that time. Another 360 million years ago killed 60 percent of all species. One 250 million years ago killed 90 percent of all life; one 220 million years ago, killed half of all species; and the famous Cretaceous-Tertiary event that destroyed the dinosaurs and half of all other species about 65 million years ago. Although the evidence for a massive comet is very strong for the C-T event, some scientists believe that some of the other extinctions may have been caused by a massive gamma ray burst received from a relatively close supernova. The gamma rays would have caused catastrophic chemical reactions in the Earth's atmosphere, destroying the Earth's protective ozone layer, and allowing lethal doses of ultraviolet radiation from the Sun to strike the surface of the Earth.
12. 13.7 billion give or take a few 100 million to be as precise as physicists believe we can be today. With the Hubble and Keck telescopes, astronomers can now see galaxy formation up to 13 billion light years from Earth. The methods used by astronomers to measure these colossal distances are, of course, subject to some error. In terms of the stirring philosophical considerations these distances produce, the probable error hardly seems to matter.
13. For an in-depth discussion of this theme, see Lynn Margulis and Dorion Sagan, Microcosmos: Four Billion Years of Evolution from Our Microbial Ancestors (New York, Summit Books, 1986), Acquiring Genomes: A Theory on the Origin of Species (Basic Books, 2003).
14. Photographs of atoms are actually pictures of the effects of our attempts to see atoms. As we will see in Chapter 8, the atom and its parts are not ordinary things that can be pictured in a three-dimensional camera image.
15. Scientific notation allows scientists to make better use of their time than writing a lot of zeros. The exponent 43 represents the number of times a decimal point would be moved from behind a 1 if this number were written out normally. Since a minus sign is used in this number, 42 zeros would be added to the front of a 1 with a decimal point at the very beginning. Thus, the Planck time is a tenth of a thousandth of a millionth of a billionth of a trillionth of trillionth of a second after the Big Bang.
16. It is important to keep in mind that the explosion has not occurred "in" space like the cherry bomb explosion. Like raisins in a baking muffin, the space between galaxies expands (like heated dough) without each galaxy moving very much with respect to the space right around it. In the late 1990s astronomers and physicists made an amazing discovery. By this time the technology and collaborative networks had progressed (including the use of a giant million dollar 340 megapixel digital camera used with one of the telescopes on Mauna Kea) such that special types of supernovas (called Type 1a) could be identified and surveyed in sufficient numbers and distances to measure how fast the expansion of the universe was taking place at different times in its history. Astronomers expected to find earlier periods had expanded faster than later periods, indicating that like a normal explosion the expansion was slowing down. Instead they found that the earlier periods had a slower expansion than what we see now, and the data indicated that the expansion began to accelerate about 7 billion years ago. It is like space is being pumped between the galaxies and the rate of pumping is increasing. For this work and essentially the discovery of dark energy, in 2011 Adam Riess, Saul Perlmutter, and Brian Schmitt received the Nobel Prize in physics.
17. Who may not be as cheerful and lighthearted as the detached theorists. See the book by Gary Taubes, Nobel Dreams, in the suggested readings at the end of this chapter.
18. For many years the U.S. government's Technology Utilization Office has published a spinoff summary. See the NASA Commercial Technology Network.
19. P. Michel, P. Farinella, and C. Froeschle, "The orbit evolution of the asteroid Eros and implications for collision with the Earth," Nature, v. 380, n. 6576, April 25, 1996, pp. 689-691.
20. Science News, July 27, 1996 p. 61, and July 28, 2001, pp. 61-63.
21. For a summary of the natural catastrophes that occur on Earth, see Charles Officer and Jake Page, Tales of the Earth: Paroxysms and Perturbations of the Blue Planet (London: Oxford University Press, 1993), and Bruce A. Bolt, Earthquakes (New York: W.H. Freeman and Co., 1993).
22. Loren Eiseley, The Immense Journey, Vintage Books ed., (New York: Random House, 1959), p. 162.
23. Bishop Ussher calculated from the Bible that all life began in 4004 B.C., and many who call themselves scientific creationists agree, although some, risking heresy, have pushed the date back to 10,000 years. Archaeopteryx lived over 100 million years ago. We will discuss scientific creationism in Chapter 3.
24. In 1994 zealous followers of Newt Gingrich, then speaker of the U.S. House of Representatives and advocate of less government restrictions on businesses, introduced a bill that would overturn the ban on chemicals used in older air-conditioning systems. Scientists had demonstrated that these chemicals were a major factor in the destruction of the ozone layer.
Suggested Readings
Galaxies, by Timothy Ferris (New York: Stewart, Tabori & Chang, 1982).
When we discuss the Big Bang theory and the details of our universe, we often assume that we are discussing the Cosmos, all that is. However, recent work in astronomy, physics, and mathematical cosmology have resulted in some scientists taking seriously the possibility that our universe is but a special case, one of many possible universes. As the Chapter notes, known now as the multiverse theory, our universe may be like a single bubble in a possibly infinite multidimensional cosmos. The laws of nature that we find in our universe, along with the spatial dimensions that we assume are identical with reality, may be but a very special case of many possible laws and spatial dimensions. Martin Rees, a theoretical astrophysicist, is a proponent of this theory.
Greene provides a grand tour of the universe via the history of and cutting edge issues in physics. As an advocate of String Theory as the possible solution for a grand unified theory of everything, this book is highly recommended not only for its inclusiveness but remarkable readability. Because of the tough going in many places, Greene provides the reader with creative analogical descriptions on almost every page, such as,
". . . just as driving due east leaves no motion for traveling north, moving light speed through space leaves no motion for traveling through time! Time stops when traveling at the speed of light through space. A watch worn by a particle of light would not tick at all. Light realizes the dreams of Ponce de Leon and the cosmetics industry: it doesn't age."