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View Full Version : Life possible on "large parts" of Mars: Study.



A.DIM
2011-Dec-12, 01:50 PM
Published in the journal Astrobiology and reported on in PhysOrg (http://www.physorg.com/news/2011-12-life-large-mars.html) ...

Charley Lineweaver's team, from the Australian National University, compared models of temperature and pressure conditions on Earth with those on Mars to estimate how much of the distant planet was liveable for Earth-like organisms.
...
"What we tried to do, simply, was take almost all of the information we could and put it together and say 'is the big picture consistent with there being life on Mars?'," the astrobiologist told AFP on Monday.

"And the simple answer is yes... There are large regions of Mars that are compatible with terrestrial life."

Blackhole
2011-Dec-14, 05:50 AM
I for one am of the opinion that Mars has harbored life in the distance past and still harbors microbial forms of life today. I believe we are the cusp of a massive discovery in space exploration which is indisputable evidence of life existing outside of planet Earth. I'm just waiting patiently for the day the front page of every news paper in the world states "NASA Discovery Martians!". It will inject some much needed adrenalin into space exploration as a whole, and in particular it will act as a geo-political force that will draw billions of government funding into space exploration, as the United States race against China and Russia to see who can become the first nation to send a manned mission to Mars.

eburacum45
2011-Dec-14, 07:38 AM
It seems likely to me that it is possible for life to exist in a great number of habitats. The new Habitable Planet Catalog hasn't got many entries yet, but that will change quite soon, I'm sure.
http://phl.upr.edu/projects/habitable-exoplanets-catalog

However the fact that a planet is potentially habitable by some sort of life does not mean that it necessarily is inhabited. There is every chance that most, if not all, of these potentially habitable planets are completely lifeless. I would also point out that the fact that a planet could possibly support life does not mean that humans could live there. Unlike Star Trek, where Captain Kirk beams down to a desert planet and can breathe the atmosphere, there is no evidence that any planet yet discovered would have any free oxygen at all. If Kirk were to beam onto any of these planets, he would probably be asphyxiated, crushed by the gravity, drowned or poisoned.

whimsyfree
2011-Dec-14, 09:53 PM
However the fact that a planet is potentially habitable by some sort of life does not mean that it necessarily is inhabited. There is every chance that most, if not all, of these potentially habitable planets are completely lifeless. I would also point out that the fact that a planet could possibly support life does not mean that humans could live there. Unlike Star Trek, where Captain Kirk beams down to a desert planet and can breathe the atmosphere, there is no evidence that any planet yet discovered would have any free oxygen at all. If Kirk were to beam onto any of these planets, he would probably be asphyxiated, crushed by the gravity, drowned or poisoned.

Boiling and freezing cannot be ruled out, simply because a planet is in the "habitable" zone. Astronomers use the word "habitable" in a very different sense than other people. The normal meaning of the word is that people can live there according to the generally accepted standards of human life. By this meaning Mars, the bottom of the sea, Antarctica, and NY apartments without running water are all not habitable. So when astronomers announce the existence of an "Earth-like" (i.e. hasn't been proved to be >10ME yet) planet in the "habitable" (i.e. for some conceivable atmosphere could support liquid water) zone people naturally start to think about moving in there. In reality there's not an exoplanet known that humans could settle.

Trakar
2011-Dec-15, 07:38 PM
It seems likely to me that it is possible for life to exist in a great number of habitats. The new Habitable Planet Catalog hasn't got many entries yet, but that will change quite soon, I'm sure.
http://phl.upr.edu/projects/habitable-exoplanets-catalog

However the fact that a planet is potentially habitable by some sort of life does not mean that it necessarily is inhabited. There is every chance that most, if not all, of these potentially habitable planets are completely lifeless. I would also point out that the fact that a planet could possibly support life does not mean that humans could live there. Unlike Star Trek, where Captain Kirk beams down to a desert planet and can breathe the atmosphere, there is no evidence that any planet yet discovered would have any free oxygen at all. If Kirk were to beam onto any of these planets, he would probably be asphyxiated, crushed by the gravity, drowned or poisoned.

most importantly, with regards to the OP, there is more to "inhabitable" than pressure and temperature.

Colin Robinson
2011-Dec-15, 11:44 PM
So when astronomers announce the existence of an "Earth-like" (i.e. hasn't been proved to be >10ME yet) planet in the "habitable" (i.e. for some conceivable atmosphere could support liquid water) zone people naturally start to think about moving in there.

If so, it's an expression of the collective egoism of many of us humans.

We need to get used to the idea that we are not the only life-form on the block.

Right here on Earth, there are many environments which are perfectly habitable to diverse living things, but not to us.

"Could there be anything living there?" is a very different question to "Could humans go there and live?"


In reality there's not an exoplanet known that humans could settle.

That may be just as well for whatever does live there. They are less likely to get hunted or fished to extinction.

iquestor
2011-Dec-16, 01:14 AM
I for one am of the opinion that Mars has harbored life in the distance past and still harbors microbial forms of life today. I believe we are the cusp of a massive discovery in space exploration which is indisputable evidence of life existing outside of planet Earth. I'm just waiting patiently for the day the front page of every news paper in the world states "NASA Discovery Martians!". It will inject some much needed adrenalin into space exploration as a whole, and in particular it will act as a geo-political force that will draw billions of government funding into space exploration, as the United States race against China and Russia to see who can become the first nation to send a manned mission to Mars.

I have the same opinion. Heres to having that announcement in the next 10 years!

Ara Pacis
2011-Dec-16, 09:49 AM
It doesn't mean anything as far as the origin of life is concerned. With material being exchanged between planets, earth life might have been imported, and perhaps vice-versa. So, life found there may merely be cousins instead of an independent lineage.

A.DIM
2011-Dec-19, 02:36 PM
most importantly, with regards to the OP, there is more to "inhabitable" than pressure and temperature.

Indeed, science has shown us many places within, on and above Earth once thought "uninhabitable" to be quite right for extremophile life. My guess is likewise we underestimate Mars' habitability and will ultimately discover extremophile life there.

A.DIM
2011-Dec-19, 02:46 PM
It doesn't mean anything as far as the origin of life is concerned. With material being exchanged between planets, earth life might have been imported, and perhaps vice-versa. So, life found there may merely be cousins instead of an independent lineage.

Agreed.
A sort of cosmic ancestry seems quite likely even if only within our own solar system.

iquestor
2011-Dec-19, 05:45 PM
if we identify life on mars it would be rather easy to tell if the two are related, or if there were two separate origin events. DNA and Chiralty would tell the tale. I think that would be the biggest new of all, if they werent related.

A.DIM
2011-Dec-21, 02:18 PM
if we identify life on mars it would be rather easy to tell if the two are related, or if there were two separate origin events. DNA and Chiralty would tell the tale. I think that would be the biggest new of all, if they werent related.
To be sure, an independent genesis event is quite the "holy grail" for astrobiologists.
Personally I think chances of such a discovery are slim to none and find it an exciting prospect the discovery that life is far more ancient and ubiquitous than previously thought.

eburacum45
2011-Dec-21, 03:01 PM
Of course, the discovery that Mars life is related to Earth life would only demonstrate that panspermia within a solar system is possible, not that life is ancient and ubiquitous. Panspermia within a solar system is probably possible, and may occur within a significant fraction of systems (anywhere between a tiny fraction of a percent and several percent of all life-bearing systems, at a guess).

Panspermia between solar systems is extremely unlikely, and probably almost never happens. The chances against life transferring by chance between one star and another are vast; the timescale required for such an event would on average be many times the currently accepted age of the universe, so it probably hasn't happened very much anywhere. Some attempt has been made by panspermia proponents to find ways of increasing the odds, but the fact is they don't work- unless life actually replicates in space, the total amount of living material in interstellar space is so small that transfers between stars is very rare indeed.

Githyanki
2011-Dec-22, 12:52 AM
So when astronomers announce the existence of an "Earth-like" (i.e. hasn't been proved to be >10ME yet) planet in the "habitable" (i.e. for some conceivable atmosphere could support liquid water) zone people naturally start to think about moving in there.

Would you like to buy real estate on Mars? It's guaranteed to have mirco-organisms in the soil which is great for growing rutabagas.

banquo's_bumble_puppy
2011-Dec-22, 05:03 PM
IMHO Mars has already been contaminated by Earth probes....take that Mars....gotcha back :-P

Garrison
2012-Jan-01, 02:11 PM
Agreed.
A sort of cosmic ancestry seems quite likely even if only within our own solar system.

Possible? Yes. Quite likely? You are going to have to offer better evidence than parts of Mars being potentially compatible with terrestrial type lifeforms.