alien life forms, do they exist?

Rob060870

Hello, I am interested to know how many readers think that we will find life in our solar system, if so when?. I am confident that we will find basic life forms in a human lifetime.

also if anyone thinks that there is more that one intelligent civilisation in our galaxy other than our own existing right now? I am not so sure on this one but hopefull, what do you think?

mathman

Definitely maybe to both questions!!!!!!!!!!!!!!!!

Chalnoth

Quote by mathman

Definitely maybe to both questions!!!!!!!!!!!!!!!!

I'll have to second that. Our knowledge is currently completely insufficient to say how common life is. So yeah, maybe.

As far as when, I suspect it will be fifty to a hundred years or more before we're able to conclusively rule out life in our solar system. Discovery of life could happen any time, if it's there.

Life elsewhere in the galaxy will be vastly harder to pinpoint. We may be able to detect planets that could support life within a decade or so, but actually verifying that it's out there is going to be massively difficult.

*Gaius Baltar*

In my opinion... Yes.

Vagn

I'd have to agree with the definately maybe, I'd say the likelihood of discovering life elsewhere in the solar system is quite likely, but whether this evolved independantly from Earth based life is a different question, as it may be possible that a meteorite from Earth contaminated the other body.

Again, their could be more intelligent life in our galaxy, but we might not necessarily discover it, due to the vast distances involved, or we could simply be the most advanced species in the galaxy, someone has to be. Personally I think there probably is intelligent life in the galaxy, although again we might not ever make contact, and I'd say that it is rather egotistical to dismiss the possibility out of hand (and would also go against the Copernican Revolution, that the Earth and our Solar System is not unique).

Chalnoth

Quote by Vagn

I'd have to agree with the definately maybe, I'd say the likelihood of discovering life elsewhere in the solar system is quite likely, but whether this evolved independantly from Earth based life is a different question, as it may be possible that a meteorite from Earth contaminated the other body.

"Quite likely" is pretty strong for life within our solar system. Compared to the Earth, everywhere else is extremely inhospitable to life as we know it, and it is currently rather speculative whether life based upon other chemical structures is even possible.

That said, Europa probably offers the best chance for life elsewhere in the solar system, followed by Mars in second.

Vagn

Quote by Chalnoth

"Quite likely" is pretty strong for life within our solar system. Compared to the Earth, everywhere else is extremely inhospitable to life as we know it, and it is currently rather speculative whether life based upon other chemical structures is even possible.

That said, Europa probably offers the best chance for life elsewhere in the solar system, followed by Mars in second.

True, I was more referring to the possibility of finding bacterial spores or dormant bacteria which originated from the Earth on some other body, but I suppose you could argue whether these are alive or not anyway.

Chronos

Find liquid water and you definitely maybe will find some form of life. Liquid water is known to exist on moons of the gas giants and probably mars. Give me an ocean with undersea volcanic vents -.

Rob060870

There is growing evidence that an ocean of liquid water lies beneath the surface of Jupiter's moon Europa. But looking for life in that ocean requires getting under an icy crust perhaps several kilometers thick.
I have heard that NASA plan to melt through the thick ice and then a submarine-like hydrobot will explore this underground ocean sending a live feed back to us!.
I think that this sort of mission is very exciting indeed.
also in a few years we will be able to analyze the atmosphere on other planets around different star systems, how interesting would it be if we found a planet in the goldilocks zone use spectral analasis and found cfc's or organic compounds even oxygen in the atmosphire!.

Chalnoth

Quote by Rob060870

There is growing evidence that an ocean of liquid water lies beneath the surface of Jupiter's moon Europa. But looking for life in that ocean requires getting under an icy crust perhaps several kilometers thick.
I have heard that NASA plan to melt through the thick ice and then a submarine-like hydrobot will explore this underground ocean sending a live feed back to us!.
I think that this sort of mission is very exciting indeed.

Well, not any time soon, that's for sure. This sort of mission would be massively, massively difficult. Consider, for a moment, what is required:
1. Power source that can melt through that much ice. This should actually be the easiest part, as all you'd need is a sufficient quantity of radioactive material. But it would need to be quite a bit more substantial than previous space-borne nuclear power sources.
2. It's not possible for the probe to communicate with the surface via radio waves, so we'd probably need some sort of cable connecting it to the surface. Since the water will quickly re-freeze as the probe passes, the cable would need to be unspooled from the probe as it sinks. If the ice is kilometers thick, this would require a kilometers-long cable! The cable, of course, will have to actually survive the descent of the probe, and remain in tact for the entire mission.
3. At a depth of several kilometers, the probe itself is going to have to deal with massive pressures. As with #1, this should be relatively easy to solve. It just hasn't been done before on this scale in space.

The biggest problem, I think, will be communicating with the surface. If the ice is actually kilometers thick, it may simply not be doable in this fashion. Our best bet might be an autonomous probe that sinks into the ice, goes through a pre-programmed routine, then ascends back to the surface through the use of some sort of ballast. Upon reaching the surface, it may communicate again, probably with a satellite set in orbit around Europa.

In any case, this sounds to me like an absolutely massive, though fascinating mission. I do hope we do something to observe the oceans under Europa's ice, but I'm suspecting it may be quite a while.

Looks like the currently-planned mission for Europa is an orbiter, and the sort of information we might glean about the ice from an orbiter may help tremendously in planning for a more ambitious mission under the ice.

jreelawg

I think that if we drill we will find life underground in Mars. I think there is even likely life underground in Venus.

Chalnoth

Quote by jreelawg

I think that if we drill we will find life underground in Mars. I think there is even likely life underground in Venus.

While there is some possibility of life underground on Mars, there is very little possibility of it on Venus. The problem with Venus is that it's too hot, and the temperature too uniform. The temperature is far too high for any sort of complex chemistry to go on, and even if there happened to be organisms that could survive in such extreme temperatures, there are no differences in temperature near the surface for organisms to take advantage of (life thrives on heat transfers from one system to another...it must make use of such heat transfers in order to survive).

*DaveC426913*

Quote by Chalnoth

The biggest problem, I think, will be communicating with the surface.

Easy solution to eliminate probe-cable or probe ascent to surface:

Code:

uponLanding(){
  turnUpReactorTemp(iceMelt);
  if (testForLife() == true){
     turnUpReactorTemp(explode);
  }
}

Earth based telescopes take it from there...

Rob060870

I believe that life in the Universe is common( it would be interesting if simple life forms were found in our solar system then I would love to know if its DNA like code was similar to ours). however Intelligent life. . . now thats a different matter!. it does appear to be very rare indeed if SETI is anything to go by.
if an advanced Civilisation exists then how long would its life span be?

Sniperman724

We really can't be the ONLY intelligent life in the universe too, there are trillions of stars, each with their own solar system filled with planets. I really think there's some form of intelligent life somewhere in the universe.

*DaveC426913*

Quote by Sniperman724

We really can't be the ONLY intelligent life in the universe too, there are trillions of stars, each with their own solar system filled with planets. I really think there's some form of intelligent life somewhere in the universe.

Isn't that kind of like saying 'there's two hundred million square miles on planet Earth, surely Everest can't be the ONLY 29,000foot tall mountain'?

*Physics-Learner*

are we "intelligent" life forms ? LOL.

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mathman Recognitions: Science Advisor	Definitely maybe to both questions!!!!!!!!!!!!!!!!

Gaius Baltar	alien life forms, do they exist? In my opinion... Yes.

Chronos Recognitions: Gold Member Science Advisor	Find liquid water and you definitely maybe will find some form of life. Liquid water is known to exist on moons of the gas giants and probably mars. Give me an ocean with undersea volcanic vents -.

jreelawg	I think that if we drill we will find life underground in Mars. I think there is even likely life underground in Venus.

Rob060870	I believe that life in the Universe is common( it would be interesting if simple life forms were found in our solar system then I would love to know if its DNA like code was similar to ours). however Intelligent life. . . now thats a different matter!. it does appear to be very rare indeed if SETI is anything to go by. if an advanced Civilisation exists then how long would its life span be?

Sniperman724	We really can't be the ONLY intelligent life in the universe too, there are trillions of stars, each with their own solar system filled with planets. I really think there's some form of intelligent life somewhere in the universe.