ByANDY FLEMING
It's
incredible to think that it's more than fourteen years since the world lost a
most remarkable astronomer, pioneer exobiologist and populariser of science -
Carl Sagan.
A
son of Jewish immigrants to the United States, Sagan was born in Brooklyn, New
York, where he spent his childhood developing an interest in astronomy. A high
achiever, he studied physics at the University of Chicago, gaining a master's
degree in 1956, before being awarded a doctorate there in 1960 in astronomy and
astrophysics. He then lectured at Harvard University until 1968, when a move to
Cornell University in Ithaca, New York beckoned. In 1971 this became a
full-time professorship that included the directorship of the Laboratory for
Planetary Studies. He also took an increasing interest in pioneering
exo-biology and publicising the Search for Extraterrestrial Intelligence
(SETI). During this period, he also became an Associate Director of the Centre
for Radio Physics and Space Research at Cornell, and later was instrumental in
lecturing at Cornell in scepticism and critical thinking.
Such
an academic career would have been amazing in itself, but Sagan had been
heavily involved in the US space program since the 1950s -- including his
celebrated briefings of the Apollo astronauts before their flights to the Moon.
However, of utmost interest to this most talented of scientists was planetary
science and the increasing number of NASA robotic missions to neighbouring
planets in the solar system.
Indeed, he was responsible for many of the biology and chemistry laboratory packs placed on these unmanned probes. He also gained worldwide attention for his idea of placing gold-anodised unalterable universal messages, onto unmanned spacecraft destined to leave our solar system. These included Pioneer 10 and 11, launched in 1972 and 1973 respectively. In the albeit slim hope of these emissaries of mankind one day millions of years from now being located by extraterrestrial
intelligence, the plaques were developed
further, and along with the Golden Record of sounds of the earth, were again
attached to the Voyager unmanned probes launched to investigate the outer solar
system in 1977.
Indeed, he was responsible for many of the biology and chemistry laboratory packs placed on these unmanned probes. He also gained worldwide attention for his idea of placing gold-anodised unalterable universal messages, onto unmanned spacecraft destined to leave our solar system. These included Pioneer 10 and 11, launched in 1972 and 1973 respectively. In the albeit slim hope of these emissaries of mankind one day millions of years from now being located by extraterrestrial
 |
| NASA. Artist concept of the Voyager 1 and 2 spacecraft. The twin spacecraft were launched within one month of each other atop a Titan IV/Centaur launch booster from Cape Canaveral, Florida. |
Sagan's
scientific research achievements and discoveries about other planets in our
solar system, and their applicability to the Earth were immense. He was, for
example pivotal to the discovery of Venus's high surface temperature of 500
degrees Celsius and its crushing atmospheric pressure, this data being gained
from the planet's radio emissions.
Whilst working for NASA at the Jet Propulsion Laboratory at Pasadena he was involved in the design and management of the first Mariner missions to Mars. Mariner 2 would later confirm Sagan's analysis that Venus was indeed the Earth's Evil Twin, and not the balmy paradise which was the conjecture of many scientists in the early 1960s. Through his studies of Venus and its runaway greenhouse effect, he identified man-made carbon dioxide emissions on the Earth as a possible cause of climate change. He was also a staunch opponent of the Cold War arms race, justifying his views by research into the effects of nuclear winter - one of the after effects of a full superpower nuclear exchange.
Whilst working for NASA at the Jet Propulsion Laboratory at Pasadena he was involved in the design and management of the first Mariner missions to Mars. Mariner 2 would later confirm Sagan's analysis that Venus was indeed the Earth's Evil Twin, and not the balmy paradise which was the conjecture of many scientists in the early 1960s. Through his studies of Venus and its runaway greenhouse effect, he identified man-made carbon dioxide emissions on the Earth as a possible cause of climate change. He was also a staunch opponent of the Cold War arms race, justifying his views by research into the effects of nuclear winter - one of the after effects of a full superpower nuclear exchange.
Sagan
was the first scientist to hypothesise that Saturn's moon Titan may possess
lakes and oceans of liquid methane or ethane, and that the reddish haze of this
moon's atmosphere was a result of complex organic molecules. This would be
confirmed after Sagan's death by the Cassini probe and associated Huygens Titan
lander. He also hypothesised that Jupiter's moon Europa had a subsurface ocean
of liquid water. This he thought possible, under an ice sheet in such low
temperatures, because of the heat from Europa's volcanism, resulting from the
massive tidal stresses on the moon due to its close proximity to the gas giant.
His
other achievements included work on the seasonal changes on the surface of
Mars, including what he correctly identified as windstorms, at a time when many
other scientists regarded them as vegetation. His interest in the possibility
of extraterrestrial life led him into demonstrating how amino acids, the
building blocks of life, can be produced by irradiating basic organic chemical
compounds found in abundance in our solar system's gas giant planets and their
many moons. In conjunction with this he also assisted Dr Frank Drake (who
formulated the now famous Drake Equation complete with its now decreasing
number of variables for calculating the total number of intelligent
extra-terrestrials capable of interstellar radio communication in the Milky
Way) in writing the Arecibo Message, beamed to interstellar space in 1974, with
the aim of informing extraterrestrials about Earth. Sagan was also a founder
member of the Planetary Society, an organisation that promotes the active
involvement of the worldwide public in planetary exploration and new forms of
propulsion such as the Solar Sail.
 |
| Carl Sagan on the set of PBS Cosmos A Personal Voyage. |
As
one of the true popularisers of astronomy and science, Sagan relished the
opportunity. The result was an inspiring, lavish and totally exquisite
thirteen-part series, first broadcast in 1980 and viewed (according to the NASA
Office of Space Science) by over 600 million people in over 60 countries
worldwide - still the most-watched science documentary series ever. It thus
comes as little surprise that the series was immediately awarded an Emmy and
Peabody Award. As Druyan notes it is a fitting tribute to the foresight of her
late husband, that even the recent digital re-mastering of the entire series required
little updating regarding factual content.
The power of Cosmos lies in Sagan's inspirational delivery of its main contention -- our oneness with the Cosmos. To view Cosmos is one of the most spiritually uplifting experiences, made all the more remarkable because it is a science series. For example, it explains how we, and all the creatures with which we share the Earth are all made of star stuff, from the elements in our own bodies including the calcium in our bones, the iron in our blood, to the carbon in each and every cell. Whilst the first light elements such as hydrogen and helium were formed at the time of the Big Bang nucleosynthesis, the heavier elements, such as nickel, copper, iron and oxygen were synthesised in the nuclear furnaces of long-dead stars, many of which became supernovae. The heavy chemical elements, were a product, once this first generation of stars had used all of their hydrogen nuclear fuel.
Sagan
movingly sums up the whole process in the introduction to both the series and the
book that in effect, the Cosmos, is all that is, all that has been, and all
that ever will be. Through a process of nearly fourteen billion years of cosmic
evolution, and later Darwinian Natural Selection, humans evolved and became a
very special part of this cosmos. In effect, through mankind, the cosmos has
evolved its very own intelligence and consciousness - star stuff harvesting
star light and enquiring about its own existence.
Carl Sagan on the set of PBS Cosmos: A Personal Voyage using an
analogy of a day and its twenty four hours to illustrate the very recent
appearance of Homo Sapiens on planet Earth (courtesy of Cosmos
Studios)
In
taking complex scientific theories and concepts such as Special Relativity,
Darwinian Selection and Atomic Theory and presenting them in a correct, yet
readily understandable form, without the need for complex mathematics, Sagan
realised the importance for mankind's future wellbeing of the public's
understanding of science and involvement in what both he and Druyan termed the
Scientific Enterprise. Despite making scientific knowledge easily accessible to
a the general public he received many criticisms from the scientific elite,
many no doubt jealous of his deserved celebrity status, or annoyed at his
attacks on vested interests. His explanation in Cosmos of Special Relativity,
"Journeys in Space and Time", remains one of the most eloquent and
understandable introductions to the subject, enticing the reader or viewer to
delve deeper.
The
issue of scientific advocacy repeatedly appears throughout Sagan's many books
including Pale Blue Dot: A Vision of the Human Future in Space and The Demon
Haunted World: Science as a Candle in the Dark. He uses the example of the
destruction of Ptolemy II's Great Royal Library in Alexandria in 415AD, and the
murder of Hypatia, its last librarian and the world's first female
mathematician by the mob, as an example of what can happen when knowledge is
kept secret by a ruling elite. The result of the destruction of the Great
Library, and the Ionian civilisation centuries before was the loss of knowledge
of incalculable value amassed over a thousand years, and the start of a dark
epoch in human history. This epoch was characterised by mysticism, bigotry,
racial and religious extremism and hatred and witchcraft, ending only with
Copernicus, Johannes Kepler, Tyco Brahe and Galileo Galilei and Giordano Bruno
(many of whom even in the seventeenth century were being persecuted by the
Roman Catholic Church, and indeed in the case of Bruno murdered for the heretic
act of speculating about a galaxy brimming with exo-planets and
extraterrestrials).
Neither
has the threat to our present civilisation from ignorance evaporated. In Pale
Blue Dot, Sagan notes how we (in western civilisation) have contrived to
produce advanced societies based primarily on high technology and science where
only a small fraction of the population has any scientific knowledge. This,
according to Sagan, coupled with the growth in religious extremism, racial
hatred, superstition, the supernatural and pseudoscience is a recipe for
disaster, and one, given our advanced weaponry will sooner, or later, explode
in our faces.
Sagan
appeals to scientists and science enthusiasts alike to become advocates for the
subject. Instrumental in both the Viking landings on Mars in the summer of 1976
and the Voyager missions to the outer planets in the 1980s, he uses the Voyager
1 "Pale Blue Dot" photograph of the Earth as an example. Senior
administrators at NASA did not want to waste resources re-configuring the
spacecraft to take a photograph of the Earth from six billion kilometres. Sagan
appealed above their heads citing the immense public interest of the
photograph. After all, he stated the US public was funding NASA and as
paymasters they had a right to witness what would become one of the most famous
photographs of all time - the Earth as a pale blue mote of dust suspended in a
sunbeam. It is by no means certain that humanity will avoid self-destruction
either through environmental degradation or through weapons of mass destruction
(and there are more than adequate quantities still available).
Stephen Hawking, Arthur C. Clarke and Carl Sagan (via satellite) discuss the Big Bang theory, God, our existence as well as the possibility of extraterrestrial life. Central Independent Television, 1988.
In
both Cosmos and Pale Blue Dot, Sagan speculates that simultaneously to gaining
interstellar communications ability, civilisations also gain atomic physics,
and perhaps more-or-less immediately use nuclear weapons to engage in self
destruction. Perhaps this is why we have not been visited by ET. Or, as Sagan
says, perhaps ET is constantly dealing with its self-generated environmental
degradation. But above all else, Sagan, in all his science advocacy is an
optimist and believes that humanity can and will rise above the challenges
posed by our very nature, the juxtaposition of our technology with beliefs, and
the disasters that nature can throw at the Earth, such as asteroid impacts. It
will be achieved, he says, by the same scientific enterprise with its proven
successful method of critically independently verified facts and theories, not
by superstitions, ufology or mysticism.
Scientists
have made astonishing leaps forward in the past 400 years, for example in
technology and medical sciences -- infact in virtually every area of modern
advanced industrial society. Compare that, Sagan says, with what other areas of
human thought and belief have provided in improving the lives of the populace.
Instead of wanting to believe in something amazing -- do something amazing. Add
to the body of human knowledge about the cosmos, or show a child the Andromeda
Galaxy. Show them how the light, the fastest thing we know has taken a
staggering 2.5 million years to reach our eyes! Inspire them to naturally
develop that innate human curiosity about science and the universe in which we
live.
Sagan
powerfully states in Cosmos that it is the birth rite of every child, of every
generation to gain knowledge about their place in the universe, and to
critically evaluate such knowledge and facts. To do less would risk being taken
in by the first charlatan character, perhaps even on a societal scale - and
there are plenty of examples of that in human history. Extraordinary claims do
indeed require extraordinary evidence. As Sagan says, there are no authorities
in science, it's a totally democratic subject, relying on verified facts, and theories
that are readily falsifiable. Yet it's also a very human and creative subject.
No one knows from which ranks the next Einstein, or Newton will come.
 |
| Sagan's Ellie Arroway character from the motion picture Contact (1997). Arroway's character was loosely based by Sagan on that of Dr Jill Tarter, one of Sagan;s Cornell University students and an astronomer at the SETI Institute, Pasadena, California. |
Dr. Ellie Arroway, after years of searching, finds conclusive radio proof of intelligent aliens, who send plans for a mysterious machine.Stars Jodie Foster, Matthew McConaughey,and Tom Skerritt
Tragically,
Sagan died in December, 1996, after a long fight with myelodysplasia, a rare
form of bone cancer at the comparatively young age of 62. A voice of reason and
science in a world where superstition and mysticism are once again in the
ascendancy, he was one of those talented individuals humanity, at a critical
juncture in its history, could least afford to lose. The challenge is for his
readers, viewers and students to pick up the gauntlet.
If
you ever endeavour to rationalise why you are so avidly interested in astronomy
and cosmology, re-visit Carl Sagan's vast astronomical bequest to the public.
He succinctly explains why we tingle at the thought of the cosmos and long to
leave the Earth -- it's in our genes to return to the stars. More importantly
you realise the immense importance of science, and of inspiring your children,
or the young generation generally with the subject. Yet you are probably
depressed at the degradation and sensationalisation of science documentaries on
television. If this is the case, and you get the chance, watch or read Cosmos
or read any of Sagan's other publications. Allow this potent master of the
Cosmos into your homes and let him inspire your families, friends and
importantly youngsters in taking an interest in science.
The
proof of Sagan's potent teaching and inspiration lies in many of his students
and colleagues who have gained leading roles in space exploration. These
include Carolyn Porco, a leading US planetary scientist, Director of the Hayden
Planetarium, New York and PBS-Nova presenter Neil deGrasse Tyson, and Steve
Squyres, principal investigator of the NASA Mars Exploration Rovers, Spirit and
Opportunity. On a personal level, had it not been for a chance viewing of the
PBS Cosmos series a five years ago, you would not be reading this now, and
neither would you see myself or my son, thoroughly relishing our visits to our
local planetarium, or our nights out under the stars with our trusty old
telescope!
Bibliography and
Recommended Reading:
Communication with
Extraterrestrial
Intelligence (MIT Press, 1973)
Mars and the Mind of
Man
(Harper & Row, 1973)
Broca's Brain:
Reflections on the Romance of Science (Ballantine Books,1974)
Other Worlds (Bantam Books, 1975)
Murmurs of Earth: The
Voyager Interstellar Record (Random House, 1977)
The Dragons of Eden:
Speculations on the Evolution of Human Intelligence (Ballantine Books,
1980)
Ann
Druyan, co-author, Shadows of Forgotten
Ancestors: A Search for Who We Are (Ballantine Books, 1993)
Pale Blue Dot: A
Vision of the Human Future in Space. Random House, (November 1994).
The Demon-Haunted World: Science as a Candle in the Dark (Ballantine Books, 1996).
The Demon-Haunted World: Science as a Candle in the Dark (Ballantine Books, 1996).
Ann
Druyan co-author, Billions and Billions:
Thoughts on Life and Death at the Brink of the Millennium (Ballantine
Books, 1997)/
The Varieties of
Scientific Experience: A Personal View of the Search for God, 1985 (Gifford
lectures, Penguin Press, 2006).
FEEL THE PB&J (PASSION, BEAUTY, AND JOY) OF THE COSMOS? SHARE IT!
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