NASA outlines hunt for extraterrestrial life

[UM-Bot]

The space agency has used new simulations to determine how best to identify a life-bearing world.

Researchers at NASA's Virtual Planetary Laboratory have been successful in accurately simulating the atmospheric chemistry of extrasolar planets in an effort to better understand the chemical compositions that would indicate the presence of life.

Read More: http://www.unexplain...errestrial-life

[Aardvark-DK]

Have they considered, that life maybe can exist outside the parameters known on earth ?

[markprice]

Have they considered, that life maybe can exist outside the parameters known on earth ?

You mean like these?

Hypothetical types of biochemistry are forms of biochemistry speculated to be scientifically viable but not proven to exist at this time. While the kinds of living beings currently known on Earth commonly use carbon for basic structural and metabolic functions, water as a solvent and DNA or RNA to define and control their form, it may be possible that undiscovered life-forms could exist that differ radically in their basic structures and biochemistry from that known to science.

The possibility of extraterrestrial life being based on these "alternative" biochemistries is a common subject in science fiction, but is also discussed in a non-fiction scientific context.

Hypothetical types of biochemistry - Wikipedia, the free encyclopedia

[Aardvark-DK]

Yep, like these...I guess I misread that part...

[Waspie_Dwarf]

Have they considered, that life maybe can exist outside the parameters known on earth ?

People often ask this question but, in the context of the search for life on other planets, it's largely irrelevant.

You can't look for forms of life you don't know exist because you don't know what would constitute a positive result. If you go searching for something but you don't know what it looks like, how would you know when you found it?

Therefore we are restricted to looking for forms of life we do know exists.

[Deleted]

Even if they find life, couldnt it be allread dead, since we look into the past?

[Waspie_Dwarf]

Even if they find life, couldnt it be allread dead, since we look into the past?

It's possible but unlikely.

The exoplanets that are close enought to detect life on are close by, astronomically speaking. We may be seeing them as they were in the past but we are only talking tens or hundreds of years ago.

[Atuke]

I subscribe to the rare Earth theory. It's highly unlikely that we will find life out there as we know it. It's possible I suppose because it happened here, but the chances and ratios and mathematics involved are astounding to why we are even here(almost makes me think there is a creator). I know the universe is vast so it is possible, but unlikely. We need to cherish what we have here because I think this is it.

[Waspie_Dwarf]

There is a huge problem with the Rare Earth hypothesis (it most certainly is not a theory). That huge problem is exactly the same one that the argument that life must be common has... they both rely on a huge number of assumptions based on a sample size of one.

The reality is we know that life exists on one planet only, Earth. What we don't know is which, if any, of the features of Earth are actually required for life.

Subscribing to the view that the universe is teeming with life or, conversely, that it is rare are, for the moment, both not much more than guess work.

Edited September 13, 2014 by Waspie_Dwarf

[David-C]

I subscribe to the rare Earth theory. It's highly unlikely that we will find life out there as we know it. It's possible I suppose because it happened here, but the chances and ratios and mathematics involved are astounding to why we are even here(almost makes me think there is a creator). I know the universe is vast so it is possible, but unlikely. We need to cherish what we have here because I think this is it.

There is around 220 billion galaxies in the visible universe. And the visible matter that makes up the universe constitutes less than 1% of the mass of the universe. Even if we are a one in a billion then there should be at least 220 more of us.

[Waspie_Dwarf]

Even if we are a one in a billion then there should be at least 220 more of us.

Only if the chances are 1 in a billion PER galaxy would your figures be right. If we are 1 in a billion there should be 100-400 of us in our galaxy alone (assuming one chance per star), that's 10-40 trillion of us in the universe. For there to be only one of us per galaxy the odds would have to be 1 in 1x10²⁴.

The thing is that it doesn't matter what odds you pick, we don't know the actual answer.

[taniwha]

And yet here we are. I think there IS DEFINITELY life on other planets, based on the odds. The universe would have to be empty of all other stars, all other planets, all other moons all of its energy to decrease the chances of life elsewhere to nil. It is abundantly clear, in the billions of billions clear, that the forces of creation leading to life is universal.

[Waspie_Dwarf]

I think there IS DEFINITELY life on other planets, based on the odds.

Which only demonstrates that you don't understand either what odds are OR what definitely means, in your case probably both.

[taniwha]

Which only demonstrates that you don't understand either what odds are OR what definitely means, in your case probably both.

If there was only one other star and one other planet in the entire universe the odds of life being outside earth would still be 50/50

[+Noteverythingisaconspiracy]

If there was only one other star and one other planet in the entire universe the odds of life being outside earth would still be 50/50

Wouldn't that depend very much on what kind of planet and what type of star ?

If we use your kind af logic there is allways a 50/50 chance of winning the lottery: Either you win or you don't.

Well I am off to buy a lottery ticket.

[Waspie_Dwarf]

If there was only one other star and one other planet in the entire universe the odds of life being outside earth would still be 50/50

As Noteverythingisaconspiracy has already shown you are just reinforcing the fact that you don't understand what odds are and how they work.

If there was only one other star and one other planet we still wouldn't know what the odds of their being life on that planet would be because we still don't know exactly what conditions are necessary for life.

One planet or trillions, it doesn't matter, you still can not extrapolate from a single data point.

Edited September 14, 2014 by Waspie_Dwarf
typo.

[psyche101]

There is a huge problem with the Rare Earth hypothesis (it most certainly is not a theory). That huge problem is exactly the same one that the argument that life must be common has... they both rely on a huge number of assumptions based on a sample size of one.

The reality is we know that life exists on one planet only, Earth. What we don't know is which, if any, of the features of Earth are actually required for life.

Subscribing to the view that the universe is teeming with life or, conversely, that it is rare are, for the moment, both not much more than guess work.

What exactly is "teeming"?

I have heard the term used in so many ways by so many people since the late great Sagan popularised the saying, and some seem to indicate it means if we look up, we should see an alien flying by, yet in a universe with billions of Galaxies, even one species per Galaxy could be regarded as "teeming" It seems to mean a great many things to many people, is there a "teeming" upper and lower limit? Even the term itself seems to be guesswork?

[taniwha]

Wouldn't that depend very much on what kind of planet and what type of star ?

If we use your kind af logic there is allways a 50/50 chance of winning the lottery: Either you win or you don't.

Well I am off to buy a lottery ticket.

Your lotto analogy made me laugh. Of course i didnt explain the rules of the game but for fun lets look at your logic...a lottery chance to find an exo planet?... Has been found...a lottery chance of finding an exo planet within a habitable zone?... Has been found... a lottery chance of finding an exo planet in a habitable zone that is earthlike?... Has been found...a lottery chance of finding an earthlike planet in a habitable zone orbiting a sunlike star?

Found,found,found,found,found!!! ...Etc etc etc, The odds of finding life....greater and greater and greater The tech we are using to do this? Better and better and better nevertheless...

...you are right it surely does depend, lets just say its a sunlike star with an earthlike planet shall we? Lets say its a coincidence but lets play fair

The rules of the game then are that there is only ONE other planet to consider in the universe so the chance of it having life is simply, from a distance 50/50. So the odds of winning or losing? the result IS known, it is the same as flipping a coin. However there will always be 100% uncertainty until the result is known.

Now the odds of winning 6 numbers and the powerball? About 1/38 million! Good luck with that ticket, friend

[Lilly]

One planet or trillions, it doesn't matter, you still can not extrapolate from a single data point.

This pretty much says it all. From just one known instance of life arising we can't extrapolate *zip*. Life could be common or rare. We simply have no way of knowing at this point in time.

[+Noteverythingisaconspiracy]

Your lotto analogy made me laugh. Of course i didnt explain the rules of the game but for fun lets look at your logic...a lottery chance to find an exo planet?... Has been found...a lottery chance of finding an exo planet within a habitable zone?... Has been found... a lottery chance of finding an exo planet in a habitable zone that is earthlike?... Has been found...a lottery chance of finding an earthlike planet in a habitable zone orbiting a sunlike star?

Found,found,found,found,found!!! ...Etc etc etc, The odds of finding life....greater and greater and greater The tech we are using to do this? Better and better and better nevertheless...

...you are right it surely does depend, lets just say its a sunlike star with an earthlike planet shall we? Lets say its a coincidence but lets play fair

The rules of the game then are that there is only ONE other planet to consider in the universe so the chance of it having life is simply, from a distance 50/50. So the odds of winning or losing? the result IS known, it is the same as flipping a coin. However there will always be 100% uncertainty until the result is known.

Now the odds of winning 6 numbers and the powerball? About 1/38 million! Good luck with that ticket, friend

Doesn't change the fact that we only knows of one planet with life. There is no way that the chance of life can be said to be 50/50 when we have no other data to base it on. That makes you statement wrong and no amount of backpedalling can change that.

Like people have said to you before, maybe you should think before you post.

[taniwha]

Doesn't change the fact that we only knows of one planet with life. There is no way that the chance of life can be said to be 50/50 when we have no other data to base it on. That makes you statement wrong and no amount of backpedalling can change that.

Like people have said to you before, maybe you should think before you post.

There is only two possible outcomes. There is life on the other planet or there isnt. Why confuse the issue? If there was no life on earth to begin with, the chances of no life on the other planet is still 50/50. There wont be life, or there will be life.

We know that life does exist on an earthlike planet arond a sunlike star, just as we know ( from evidence to date) that life does not exist on a marslike planet around a sunlike star. Life has a way of existing as it also has a way of non existing.

At what point do you think the chance of life on another planet becomes 50%? What about 70% or 99%? Or do you think there is NO chance at all unless its slapping you in the face?

Do you imagine that if the earth didnt exist, that would mean the entire universe is become lifeless? I didnt think so.

You see, because of the enourmous amount of planets out there, odds of finding life need to be reduced by a large degree, so its only logical to search for and explore earthlikes first before extending to other planet types. And i think we will be rewarded soon enough.

[taniwha]

This pretty much says it all. From just one known instance of life arising we can't extrapolate *zip*. Life could be common or rare. We simply have no way of knowing at this point in time.

Wise words Lilly. Life is numerous and varied, its persistant and stubborn, its here to stay.

I think life might be on a universal scale common, just as suns are common, and planets are common and moons are common.

Common being the common theme.

[+Noteverythingisaconspiracy]

There is only two possible outcomes. There is life on the other planet or there isnt. Why confuse the issue? If there was no life on earth to begin with, the chances of no life on the other planet is still 50/50. There wont be life, or there will be life.

We know that life does exist on an earthlike planet arond a sunlike star, just as we know ( from evidence to date) that life does not exist on a marslike planet around a sunlike star. Life has a way of existing as it also has a way of non existing.

At what point do you think the chance of life on another planet becomes 50%? What about 70% or 99%? Or do you think there is NO chance at all unless its slapping you in the face?

Do you imagine that if the earth didnt exist, that would mean the entire universe is become lifeless? I didnt think so.

You see, because of the enourmous amount of planets out there, odds of finding life need to be reduced by a large degree, so its only logical to search for and explore earthlikes first before extending to other planet types. And i think we will be rewarded soon enough.

My entire point is that you can't put a statistical probability on anything based on just one data point. How is that so hard to understand ?

What you are doing is not statistics, it is your opinion.

By the way I do agree that there is most likely life elsewhere in the universe, but it is just that - a belief !

[Waspie_Dwarf]

taniwha, you continue to make the same mistake in thread after thread, believing that what you think is important, it isn't, it really, REALLY isn't.

Science is not some sort of democracy where all opinions are equal, it is a dictatorship of fact and evidence in which opinion counts for little.

Worse still, even for the little that opinion does count, the opinion of the experts hugely outweighs the opinion of the unknowing, the ignorant and the uneducated.

The opinion of someone that doesn't know what a shadow is, or who calculates that every star has 4000 habitable planets orbiting it and sees no problem with this, is totally irrelevant.

I am at peace with the fact that my opinion is almost entirely worthless, it's why I post on topic links to evidence or the opinion of real experts when I post. It istime you can to peace with the fact that yours has absolutely no value at all

[taniwha]

What exactly is "teeming"?

I have heard the term used in so many ways by so many people since the late great Sagan popularised the saying, and some seem to indicate it means if we look up, we should see an alien flying by, yet in a universe with billions of Galaxies, even one species per Galaxy could be regarded as "teeming" It seems to mean a great many things to many people, is there a "teeming" upper and lower limit? Even the term itself seems to be guesswork?

I think the universe might be "teeming" with plant life. Perhaps there is one such planet hosting oceans full of forests, swaying back and forth, patiently soaking up the starlight for millions of years, rainbows of beautifully flouresent dancing colours, evolving intelligence befitting of sea creatures, majestically oblivious to the approaching asteroid....lol.