Larry Klaes (firstname.lastname@example.org)
Wed, 14 Jul 1999 19:39:41 -0400
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>Date: Wed, 14 Jul 1999 16:40:51 +0200
>From: "Chris Penberthy" <firstname.lastname@example.org>
>X-Mailer: Mozilla 4.04 [en] (WinNT; I)
>Subject: [acc-list] FW: Message from John Sherwood
> Here's a mail that John has asked me to forward to the list.
>John C. Sherwood wrote:
>The following article, which refers to ACC briefly, is something I
>mentioned early last week, and am asking Chris Penberthy to pass on to
>the list, now that I've gone off-list in preparation for my trip to the
>United Kingdom and household move from Michigan to Pennsylvania. I'll be
>re-joining the list later this year, probably in September. See you
>Exploration in the new millennium: Sea, space may hold secret of life
>By JOHN YAUKEY
>Gannett News Service
>WASHINGTON - Half a millennium ago, Copernicus evicted us from the
>center of the universe by pointing out that Earth orbits the sun.
>Centuries later, Darwin challenged divine creation with evolution.
>Now, many scientists say we are poised for yet another titanic
>revelation about ourselves and our sense of place in the cosmos.
>”We are at a fork in the road,” said New York University chemistry
>professor Robert Shapiro, author of the recently published book ”Planetary
>Dreams,” where he suggests the notion that life is unique to Earth could
>prove as implausible as theories of divine creation. ”Our search for other
>life is going to help decide which of two very different views of the
>universe is correct.”
>Down one road, we discover life is common in the universe; that the cosmos
>is in the business of making life. Space probes suggest several of the
>solar system’s planets and moons are harboring microbes, or eventually
>could. And, as with Earth, where there are bugs, there may eventually be
>intelligent life. Thus we conclude a high probability of thinking
>extraterrestrials lurking somewhere.
>The other leads to a kind of biological existentialism. We concede we
>live on a freakish Eden, adrift in an otherwise lifeless sea. Probes sent to
>the vast oceans of the Jovian moon Europa, which scientists are eager to
>explore for possible life, find only lifeless slush. It appears the once
>warm, wet Mars never nursed even the most primitive bacteria. None of
>the recently discovered planets outside the solar system show signs of water
>or atmospheric chemistry indicative of life below. We slowly conclude if
>there is life, it’s so far away or foreign in structure we’ll never find
>it, or recognize it if we do.
>At stake is nothing short of our view of the universe and its capacity
>”Confirmation of life elsewhere - even the most primitive of microbes -
>would be the defining discovery of humankind,” said American University
>astrophysicist Richard Berendzen. ”And we live in a time when we will
>soon be able to look for life outside our own solar system.”
>In their search to better characterize the cosmos as either nurturing or
>hostile, scientists are exploring not only the black pastures of space
>but also the silt-enshrouded canyons of the sea.
>The two seemingly opposite environments have become linked as scientists
>study newly discovered microbes thriving in the scalding, lava-heated
>vents deep in the sea and wonder if such primitive, but tenacious life
>could arise elsewhere.
><B>The deep, hot biosphere<P>
>In 1977, a small submarine dubbed Alvin descended to about 8,000 feet
>near the Galapagos Islands where the sea floor was cracking under the
>pressure of volcanic activity.
>As the searchlights scanned the sea floor, they revealed among the barren
>expanses dense communities of life clustered around vents spewing
>lava-heated water and debris into the frigid surroundings. Researchers
>were astonished to discover the food chain here was built upon previously
>unknown forms of heat-loving microbes. These robust organisms thrive in
>the eternal night of the ocean floor bathed in the very elements of hell -
>inky, roiling clouds of 600-degree water and sulfur.
>Temperatures can only go so high before all biochemistry becomes
>But at the limits, some microbes - dubbed extremophiles for their love
>of extreme environments - can survive; even thrive.
>Some can endure intense cold while others can withstand crushing pressure
>or toxic environments that would kill the mesophiles of this world, or
>those creatures that prefer medium conditions.
>But since medium conditions are unique to Earth as far as we know,
>scientists have found the extremes much more interesting to study as
>they explore how life could develop on other planets.
>Many scientists now regard deep-sea thermal vents as a dark window into
>the primordial conditions that gave rise to life billions of years ago
>when Earth was far less hospitable.
>Indeed, the study of extremophiles is changing the way scientists think
>about the nature and limits of life and the ease with which it can arise
>- on Earth and possibly other worlds.
>”People are setting up all kinds of experiments to mimic these
>conditions,” said James Ferris, director of NASA’s Center for the Origins
>of Life. ”There’s all kinds of new thinking going on in origins of life
>One of the most hotly debated new ideas, known as the theory of the deep,
>hot biosphere, turns the traditional explanation of genesis upside down.
>This still-controversial model has potentially far-reaching implications
>for virtually all theories about life formation.
>Formulated largely by Cornell University aromer Thomas Gold, the theory
>proposes that life arose not near the surface of the early seas where it
>drew energy from sunlight, but rather from primitive microbes thriving in
>the Stygian depths of the planet, feeding on its rich supplies of
>”We suffer from surface chauvinism,” Gold argued in a recent interview
>following the publication of his book ”The Deep Hot Biosphere.” ”It is far
>more likely that life began deep within the planet. But because of where
>we live we don’t think much about the life below us.”
>There, sedimentary rocks supply chemical energy to microbes in the form
>of oxidized minerals. Extremophiles are so adept at extracting this
>nourishment they thrive even in igneous rock - solidified lava with
>almost no organics.
>The life that covers the planet, Gold believes, migrated upward through
>deep-sea vents, eventually trading its primitive ability to feed on
>chemical energy for the more complex process of photosynthesis.
>According to this theory, humans and all other surface life are the
>progeny not of some nurturing Eden, but of a hellish netherworld that
>spewed its creation into the ancient seas.
>The beauty of this ”inverted genesis” is that by simplifying life’s
>origins - by tracing them to more primitive and durable subterranean
>life - it raises the odds that life could form on hostile planets.
>In other words, the theory greatly reduces the lowest common denominator
>”This makes life elsewhere far more probable, because the likelihood of
>living conditions like those at the Earth’s surface are so improbable,”
>In 1997, NASA’s space probe Galileo hurtled past the Jovian moon Europa,
>snapping a series of photos that left scientists slack-jawed. To the
>untrained eye, Europa’s surface looked scratched.
>To scientists those riven lines indicated glacial plates floating on a
>liquid, probably water. Scientists had suspected Europa was wet, but
>these images were almost proof.
>Water, as opposed to ice, is so vital in the search for life because it
>allows elements to mingle and form the complex organics necessary for all
>known biology. Warmed by tidal heat, Europa’s apparent liquid ocean is
>prompting intense curiosity about possible life there and whether or not
>it might resemble Earth’s extremophiles.
>Those free of peer review’s constraints have already fled ahead with
>speculation. In his novel ”3001,” famed science fiction writer Arthur C.
>Clarke envisions Europa as home to a diversity of life thriving around a
>network of hot, deep-sea vents.
>Scientists, however, have applied the brakes.
>”Is there water there (Europa) now, or are we seeing evidence of water a
>million years ago?” said Carl Pilcher, director of solar system
>exploration at NASA. ”We need to be able to answer that and a lot of
>other questions before we start talking about life.”
>The heightened interest in Europa comes at a time when scientists are
>increasingly considering the possibility that several planets and
>satellites in our own solar system might contain liquid water and
>chemical systems evolving in the direction of life.
>In addition to Europa, two of Saturn’s moons look intriguing. Enceladus
>shows signs of an icy surface and may have flowing water. Saturn’s icy
>red moon Titan has captured attention as a potential incubator of complex
>organics. Now en route, the Cassini space probe will study Titan for
>clues about how organics form there.
><B>The search is on<P>
>The study of extremophiles on Earth and the possibility of liquid water
>on other planets together are rewriting the odds on extraterrestrial life.
>NASA’s agenda is heavy with missions that will look for life and its
>Robotic spacecraft have already explored more than 70 planets and
>satellites within the solar system while astronomers have discovered
>what appear to be planets circling as many as eight sun-like stars.
>Meanwhile, other disciplines - from exobiology, which theorizes about
>otherworldly life, to oceanography, geology and biology - are all
>contributing to a massive pool of data about life here and what it can
>tell us about the likelihood of life elsewhere.
>The evidence may point to a living cosmos.
>Or we may encounter only barren wastelands, vacant even of signs of
>Research and exploration over the coming decades will help determine
>which of these two very different views of the cosmos prevails.
>John C. Sherwood
>MysteryVisits.com, 120 W. Hanover St., Marshall, MI 49068, (616)
>Opinion page editor emeritus, Battle Creek (MI) Enquirer
>Artistic director emeritus, The Victorian Villa Inn, Union City, MI,
>USA, (800) 34-VILLA for inquiries
>E-mail: email@example.com | firstname.lastname@example.org
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