Posted on 09/13/2006 2:08:21 PM PDT by PatrickHenry
A comprehensive review by leading scientists about our Solar System which speculates on the possibility of life on other planets has been published.
Solar System Update brings together the work of 19 physicists, astronomers, and climatologists from Europe and the USA in 12 chapters on the sun, the main planets and comets.
The book, co-edited by Dr Philippe Blondel, of the University of Bath, highlights the many recent discoveries and in particular the amount of water, one of the essentials for life, found in the Solar System.
Recent studies have revealed ice in craters on Mercury, the closest planet to the sun, and that liquid water may once have existed on the surface of Mars and may still be there underground.
In addition, liquid water may exist on moons around Jupiter, in particular Europa, Ganymede and Callisto, underneath a surface of ice.
In his chapter The Habitability of Mars: Past and Present, Thomas McCollom, of the Center for Astrobiology at the University of Colorado, USA, says that though the temperatures on Mars, as low as minus 120 Centigrade, mean that water cannot exist on the surface, there may be a "planet-wide liquid aquifer at some depth in its crust." There is also geological evidence that water has flowed on the surface in the past.
“It seems increasingly apparent that habitable environments very likely exist on Mars today, and may have been considerably more diverse and abundant in the past,” he writes.
In his chapter The Icy Moons of Jupiter, Richard Greenberg, of the Department of Planetary Sciences at the University of Arizona, USA, says: “There is an unusually strong motivation to continue to pursue studies of the icy satellites.”
He says that three large moons of Jupiter “probably have liquid water layers, and one, Europa, almost certainly has an ocean just below the surface. Naturally liquid water raises the possibility of extraterrestrial life.”
However, if the surface ice were very thick, this would cut the water below off from oxygen and sunlight which are important for most forms of life on Earth, and so might have prevented life from developing.
Dr Blondel, who works in the University of Bath’s Department of Physics, took 18 months to edit the book, with his co-editor Dr John Mason.
“This book sets out how much water and ice there is in the solar system," said Dr Blondel. “This obviously has implications for our search for extra-terrestrial life.
“By understanding better how the climates of planets like Mars and Venus have evolved, we can understand more about climate change on Earth.
“For instance, the very hot and cloudy climate of Venus is likely to have developed after a runaway greenhouse effect, and the more we know about this the more we can understand some of the challenges caused by our climate change on Earth."
The full list of the contributors is:
[See list at original article]
The book is published by Springer, Germany and Praxis, UK.
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The operative word: "SPECULATES"
The question is whether life is the exception or the rule.
Either answer will have implications that are awe-inspiring, if you are inclined to awe.
I can't wait for them to start core-drilling; I want to see whats under Martian soil.
This is not unlike the argument over extra solar system planets a few years ago.
“For instance, the very hot and cloudy climate of Venus is likely to have developed after a runaway greenhouse effect, and the more we know about this the more we can understand some of the challenges caused by our climate change on Earth."
Interesting up until that point. I guess if the USSC can use foreign law, we can use interplanetary evidence to support global warming.
Speculation by "19 physicists, astronomers, and climatologists" who are expressing opinions about their fields of expertise is worthy of consideration. But if you feel otherwise, that's up to you.
I suspect there are interesting things to see in the Martian canyons as well.
You are correct, is life the rule or the exception. Since life has been found on the earth almost everywhere a person looks, including some very hostile environments, I want to believe it is the rule, not the exception. One of my hopes is, before I die, we find some form of life on another planet. Even if it is just a microbe on Mars I would love to see that.
If I remember correctly, the atmosphere of Venus was considered a result of runaway greenhouse effect long before global warming on Earth was an issue. That it is mentioned here is hardly an attempt to link to global warming.
I'm no sure how we get to "very likely" from "30 years of exploratory spacecraft missions without finding anything." I'd go with "possibly."
If you landed a spacecraft anywhere on earth, you'd find life almost instantly.
This shows that once life starts on a planet then it becomes pervasive.
Since life is not readily detectable on other planets with supposedly habitable environments it is more likely that no life exists there and that the beginning of life is the exception.
I believe the quoted individual is saying that the more we know about Venus's runaway greenhouse effect, the more we will know about the effects of terrestrial climate change. By climate change, I submit that he means global warming.
If you are going to misquote JBS Haldane, it might be polite to at least credit him, IMHO
I would have misquoted Sagan because I was that's who I thought I was misquoting. LOL
Is this a prayer thread? I need to know before posting science.
First contact may look like this........
http://www.badmovies.org/multimedia/movies6/darkstar1.mpg
There is a first for everything and as time goes by, I'm beginning to think that we are the first intelligent lifeforms........(but there are many, many days in which I question "Intelligent")
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