Searching for Alien life

hi guys,

just watching a ufo documentary and whilst watching the documentary I noticed that most scientists etc were saying that we need to search for oxygen to find alien life as thats what the "must" need to breath and live as we do. but what I don't understand is why are they not thinking outside the box, why must the breath oxygen, why can they not evolve to breath other gases ?

thoughts ?

a reply to: Bfletcher618

Well, back up to the famous twin Viking missions to Mars in the middle through late 1970s. The Viging landers both carried "search for life" experiments that dug into the soil and tested the sample in little ovens for out-gassing of materials that our earthly life forms would produce. They found nothing of the sort, but they did get some interesting results that they simply disallowed as being indicative of former life because they have this little confining box of thinking what is possible or not.

Actually, the situation boils down to the main reason UFOs are ignored by government and science. They don't want to accept something that they don't accept. That age-old bugaboo used to be called NIH, Not Invented Here. But, hang on, things are changing. It is dawning on science that we just may be wrong in a lot of things from physics to consciousness to humans being number one in the universe.

a reply to: Bfletcher618

If we're talking about discovering places 'out there' that can support life as we know it, then not only oxygen but liquid water, protection from the suns radiation, etc. are all important. Let alone a stable enough environment to thrive and multiply in.

Then well, introducing life itself...

Considering how old the universe is there is bound to be life most everywhere it can flourish.

People want to see 'proof' of aliens' they should look in the mirror.

originally posted by: Bfletcher618
hi guys,

just watching a ufo documentary and whilst watching the documentary I noticed that most scientists etc were saying that we need to search for oxygen to find alien life as thats what the "must" need to breath and live as we do. but what I don't understand is why are they not thinking outside the box, why must the breath oxygen, why can they not evolve to breath other gases ?

thoughts ?

You make a good point and it is valid, there are scientists that have of course postulated such but it is very difficult so looking for life based on a similar chemical nature to our own is far easier as we know what to look for.

But there is no reason that a cold world far from the sun may not harbor totally alien life, life that for example evolves in an ocean of liquid methane or even nitrogen and is based on different chemical reactions' to our form of life, that breath's a different gas so long as there is a reactive property that it can gain energy from in whatever analogue of a cell it's life form would be based on (or no gas at all but has some other method of metabolizing and producing energy in its environment).

Or a life form evolved on a world so close to it's super hot sun that liquid metals form it's ocean, we can only postulate.
But of course life similar to us is more likely for us to be able to communicate with than life that is really totally alien to us.

Though I hate to think about the guy given his liking for little boy's Arthur C Clark had giant jellyfish like life form's floating the cloud's of a gas giant in one of his sci fi novel's.

It is sobering to think also that some form's of intelligence may think so slowly that we may not even realize they are sentient while other's may think so fast that it is we that seem like inanimate being's to them.

This notion that life needs oxygen and water to thrive is completely ridiculous and incredibly ignorant to think in that manner. Life here yes needs it because that's what the environment has given us.

Life will always find a way.

More people need to be a little more creative and think out side the box. If you haven't noticed. Science is getting a lot of things wrong so they have no clue along with the rest of us.

a reply to: Bfletcher618

There is some thinking along this line. There are some scientists who think we could possibly find some kind of life on Saturns largest moon, with an atmosphere, Titan. It would be life as we don't know it, having to breath methane and other gasses, but certainly not oxygen there, or very little. So there are some who believe as I do too, that we should look for life as we don't know it, and not just oxygen based, carbon based life.

a reply to: Bfletcher618


I've never heard them say that we MUST find oxygen because life ONLY breathes oxygen. Sciences know for a fact that life does not need oxygen because for the first 1/5 to 1/4 of the history of life on Earth, that life was anaerobic life (life that does not use oxygen, and in fact finds oxygen to be toxic.

It was not until about 800 Million years after life first emerged did oxygen begin to appear in abundance in the atmosphere and life on Earth began to evolve to use oxygen.


What you probably heard them say was that the search for life on exoplanets will probably revolve around astronomers looking for an abundance of oxygen in the atmospheres of those exoplanets (they can analyze the atmosphere by analyzing their light spectras).

The reason they search for oxygen is because as far as anyone knows, the only way to get a relative abundance of elemental oxygen in an atmosphere (such as the Earth with it's 20% oxygen atmosphere) is through life processes. So if they detect a certain level of oxygen in an exoplanet's spectral analysis, then that would strongly suggest life.


That's how they plan to find life -- by looking at the balances of chemicals and elements in an atmosphere, and look for unbalances that cannot be explained by other natural (non-life) processes. The reason they search for oxygen is because it is "Life as we know it", and life as we best understand it. "Life as we DON'T know it" would be harder to search for, because we wouldn't even be sure what to even look for.

However, that does not stop some astrobiologists for looking for "Life as we DON'T know it". For example (and as 'dat1059' in the post above me alluded to), Chris McKay from NASA suggests that certain chemical imbalances of hydrogen and Acetylene in the atmosphere of Saturn's moon Titan could possibly suggest a weird for of microbe that consumes hydrogen and acetylene on Titan. Granted, as McKay points out, there are non-life processes that could explain these imbalances, but his [point is that it COULD be due to life.

Here is a NASA article about that:

NASA -- What is Consuming Hydrogen and Acetylene on Titan?

This lack of acetylene is important because that chemical would likely be the best energy source for a methane-based life on Titan, said Chris McKay, an astrobiologist at NASA Ames Research Center, Moffett Field, Calif., who proposed a set of conditions necessary for this kind of methane-based life on Titan in 2005. One interpretation of the acetylene data is that the hydrocarbon is being consumed as food. But McKay said the flow of hydrogen is even more critical because all of their proposed mechanisms involved the consumption of hydrogen.

"We suggested hydrogen consumption because it's the obvious gas for life to consume on Titan, similar to the way we consume oxygen on Earth," McKay said. "If these signs do turn out to be a sign of life, it would be doubly exciting because it would represent a second form of life independent from water-based life on Earth."

So no -- you would be extremely hard pressed to find a serious scientist who says "Life can only exist by breathing oxygen".