“One lifeforms deadly radiation may be another lifeforms lunch.”
David Grinspoon, member of the science team for NASA’s Mars rover, and interdisciplinary scientist for the European Space Agency’s Venus Express mission.
Prominent astrobiologists have warned that we humans may be blinded by our familiarity with carbon and Earth-like conditions. In other words, what we're looking for may not even lie in our version of a "sweet spot". After all, even here on Earth, one species "sweet spot" is another species worst nightmare. In any case, it is not beyond the realm of feasibility that our first encounter with extraterrestrial life will not be a solely carbon-based occasion.
Here’s our editorial team’s selection of what the participants in the Daily Galaxy “Life in the Solar System” poll think are the most likely candidates for the first discovery of life in our little corner of the Milky Way.
Life, here on our own little rocky, wet ball of planet, it turns out is quite adaptable to any number of hostile environments! As we find more, and varied extremophiles, I see that our Solar System could possibly host some form of life as well. My romantic vote would go to Mars, especially under the polar ice caps. And honestly, I think that we’ll have the politics, and money (sorry to have to introduce those topics into an otherwise polite conversation) to do the kinds of explorations there, that will then yield other discoveries elsewhere in our Solar System.
Posted by: jamerz
I think that all those worlds are equally probable to host life. As the first comment says, life can be found in extremely ‘hostile’ environments in our own blue planet. Now, the question I have around in my head is: if we find life out there, will we find an isolated species or a whole ecosystem with several species and different environments just like on Earth? I guess it depends of how long ago the life was originated.
Anyways, my vote goes to Europa due to my love for “2001: A space odyssey”
While Titan is a dynamic world with abundant organics, I would still put my money on Europa instead. Europa has tidal heating and a potentially VAST subsurface ocean. If life never did get started in the oceans of Europa I would interpret that to mean that life, even microbial life, must be far rarer than we might like to think.
Posted by: Sagan
I think the possibility of airborne life forms on Venus is too much of a stretch — at least for me. However, based on our growing knowledge of extremeophile life on earth, the possibility or probability of finding life in one or more of the other settings you described seems reasonably good.
The best bet, it seems to me, would be subterranean bacteria of some sort on Mars, probably near some geothermal vents where water can still be liquid and deep enough below the surface to protect them from the the other hazards of the Martian planetary surface. Certain moons of Jupiter and Saturn also present interesting possibilities.
Regarding substances that can form the basis of life — while ammonia is intriguing, for the time being lets stick with water.
Last point — would we recognize alien life if we found it? I think this might be one of the strongest reasons for sending humans on these exploratory missions. The robot sensors we have sent up to this point are just too limited in terms of sensors and capabilities to handle the vast number of possibilities that need to be considered/explored in an exhaustive search for life on a planet like Mars. Time to get off our collective butts and get some people up there to take a look around.
Posted by: stargazer
Life is waiting in seemingly every nook and cranny of the cosmos. However, beauty is in the eye of the beholder, and our limited understanding of life and the cosmos will filter our findings. Initially we will find life similar to our planets own developments even if only in ancient preservations. As we progress in our understanding of this omniverse we will learn to recognize life in forms not previously imagined outside of paperbacks. Though we may only find superior life forms when they decide to find us as our destructive nature and limited understanding have us still riding the shortbus of the galaxy.
Posted by: SiliconJon
Mars looks surprisingly Terrestrial, but I’m almost willing to put my money on Europa, Titan & Enceladus to win, place & show. The 3 moons have tidal pull from larger bodies ( Jupiter & Saturn ) possible sources of heating from same, & Titan has a substantial atmosphere. Europa possibly has sub - surface liquid seas or lakes where life could take hold, & ice to shield life from the radiation of Jupiter’s belts. Enceladus appears to have equal conditions.
We might find life on Mars, but it would be micro - fossils, I would be sure.
Posted by: EvilCosmicMonkeyfrom Knoxville
Ceres is where it’s at! For some reason everyone has overlooked this miniplanet between Mars and Jupiter… but I have a hunch life is lurking there! (Lots of water there.) It’s kinda like a mini version of Mars, but with water all over the place, supposedly.
And if it doesn’t have life, then it would be an ideal spot for a first human colony. (It’s a better choice than Mars given that Ceres has lower gravity than Mars, and would not trap the first explorers in a difficult to exit gravity well).
From Ceres you could launch new missions to nearby Mars or Europa, since Ceres is between those 2 points.
Europa is the obvious second choice for me, in terms of probability for life.
Posted by: Velocity Wave
To me it seems inevitable that extra-terrestrial life will first be discovered on Mars. There have been so very many asteroidal impacts on earth, after life was well established, that it would seem neglectful to think that microbial organisms did not ride a stone rocket from our planet to Mars. I feel certain we’ll find life forms on Mars that had their origins on earth.
Posted by: Vernon Goins
I give Europa and Enceledas maybe a 25% chance each of having microbial life, and maybe 10% for having multicellular life. I think it’s a safe bet that humans are the most advanced lifeforms in the solar system, certainly the only life that uses a high degree of technology.
Life in the clouds of Venus or any of the gas giants is just too problematic in too many ways. High radiation levels, scarcity of resources, extremely high or low temperatures & pressures, high turbulence, etc. Perhaps an extremely rugged bacteria could pull it off (I doubt even any extremophiles could though), but even then, evolving to that point would require a much more stable environment for the hundreds of millions of years to reach that point. Venus’ surface is just way too hot, the gas giants have no surface to speak of at all, and none of them has any meaningful amounts of water vapor, never mind liquid water.
As for life on Mars, I suppose it’s possible, but probably not very likely. It would certainly have to be subterranean, which would probably limit it to being microbial, or at most simple multicellular. It would of course be very cool to find life on Mars, but I’m not holding my breath.
Posted by: Andrew T
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