NASA about to announce flowing water on Mars?

[prand]

Guvernator said:

That's not to say that there might not be life in other forms, for instance it's been suggested that silicon based life might also be another possibility but since there aren't any examples on Earth and we've not encountered it yet, it will be harder to find and in a universe that's as vast as the one we occupy, it probably makes a lot more sense, at least initially to try to find life that's similar to our own basic composition before we start looking for it elsewhere.

I agree, strange the scientist had to pause in his answer, as in the same way there are billions and billions of galaxies and billions of planets that could sustain life as we know it, the odds would also suggest that there would be other element based life forms out there too.

But we're perhaps not so used to searching for them, recognising the signs, such as we're focusing on searching in the goldilocks zone around suns for planets with the right temperature and gas signatures which would be good for human habitation, not looking for super gas giants or frozen worlds which would be difficult to sustain human or other carbon based life.

[travel is dangerous]

There are some fundamental properties of silicon that make its chemistry really quite different to carbon. These tend to prevent the formation of complex silicon compounds analogous to the carbon based compounds that comprise living things.

However, NH3 is not so different from H2O and it's conceivable that this could be a suitable solvent for life.

[footnote]

Cheers all - clarified a "life, but not as we know it" scenario

[Eric Mc]

I've always liked this cartoon (I first came across it around 50 years ago) -

[skeeterm5]

footnote said:

Not being a scientist myself, I thought Humphreys had asked a great question but the scientist's hesitation prompted me to raise the same question on here.

I'm guessing that the evidence for the argument that all life is water-dependent is exclusively based on our current knowledge of life on earth and that there's no proof for either side of the argument - it's just beyond current human knowledge?

If the universe is truly infinite then the answer has to be yes, there must be life that is not water dependent.

S

[Einion Yrth]

skeeterm5 said:

If the universe is truly infinite then the answer has to be yes, there must be life that is not water dependent.

S

Only if the existence of such life is consistent with the physical laws of the universe; in an infinite universe, anything that is physically possible will occur an infinite number of times, nothing impossible ever will.

I don't know whether life not dependent upon water is possible, or not.

[Simpo Two]

footnote said:

I caught a few minutes of John Humphrys chatting with a scientist on R4 this morning and although I missed the beginning, it seemed to be about water on Mars and the general necessity of water for life - as we know it.

The scientist mentioned a NASA dictum - "Follow the water" meaning, if you find water you are more likely to find life.

Humphreys self-deprecatingly queried, while he accepted it may be a very stupid question, was there any possibility of life anywhere that did not depend on water.

Scientist went silent - possibly perplexed or bemused or stumped - hard to tell, and eventually replied that he believed that life was probably always going to be water-dependent, although he acknowledged that some critters lived in the most difficult of environments.

Not being a scientist myself, I thought Humphreys had asked a great question but the scientist's hesitation prompted me to raise the same question on here.

I'm guessing that the evidence for the argument that all life is water-dependent is exclusively based on our current knowledge of life on earth and that there's no proof for either side of the argument - it's just beyond current human knowledge?

I heard it too. The scientist hesitated because there's no known life that doesn't use water as the solvent. However if you switch from known biology to pure chemistry, ammonia is plausible. Human knowledge is very limited but chemistry is chemistry!

Note that only about 1% of journos know anything about science. Why would they? They did media studies...

[footnote]

Simpo Two said:

footnote said:

I caught a few minutes of John Humphrys chatting with a scientist on R4 this morning and although I missed the beginning, it seemed to be about water on Mars and the general necessity of water for life - as we know it.

The scientist mentioned a NASA dictum - "Follow the water" meaning, if you find water you are more likely to find life.

Humphreys self-deprecatingly queried, while he accepted it may be a very stupid question, was there any possibility of life anywhere that did not depend on water.

Scientist went silent - possibly perplexed or bemused or stumped - hard to tell, and eventually replied that he believed that life was probably always going to be water-dependent, although he acknowledged that some critters lived in the most difficult of environments.

Not being a scientist myself, I thought Humphreys had asked a great question but the scientist's hesitation prompted me to raise the same question on here.

I'm guessing that the evidence for the argument that all life is water-dependent is exclusively based on our current knowledge of life on earth and that there's no proof for either side of the argument - it's just beyond current human knowledge?

I heard it too. The scientist hesitated because there's no known life that doesn't use water as the solvent. However if you switch from known biology to pure chemistry, ammonia is plausible. Human knowledge is very limited but chemistry is chemistry!

Note that only about 1% of journos know anything about science. Why would they? They did media studies...

Ha ha - sadly, the odds on anybody at the Beeb having a degree in media studies are fairly slim - accessibility is something of an issue there - with most entrants being Oxbridge educated.

Humphrys is a famous exception of course, not having been to university at all, but at 74, it's fair to say he's picked up a bit of knowledge along the way.

I think it's true that most journalists know little about science (also statistics and finance) but it's also true that many scientists know little about how to communicate their subjects effectively to a non-scientist (but not children) audience.

They seem to only appear whenever there is a big project needing funding (or a 'discovery') and very often present beliefs as facts, no doubt in an attempt to dumb the subject down enough for the dafties to understand but it can make many of their media appearances seem a bit bullstty.

The media always focus on the zany and sometimes the scientists seem to follow that lead rather than focus on the subject.

[travel is dangerous]

one of the issues with ammonia as a solvent for life is that it forms weaker hydrogren bonds than water does.

the formation of these bonds between water molecules (and the breaking of them between water molecules and large macromolecules) is why your proteins (e.g. haemoglobin, which carries oxygen around in your blood) which are just long chains of amino acids can reliably and regularly (or even at all) fold into the correct 3D shape for them to work.

If you replace water with ammonia it's quite likely that although ammonia is a perfectly good solvent for organic molecules, the thermodynamic driving force for protein folding will be totally removed and big biological macromolecules won't be able to exist in the same way in ammonia as they do in water.

[MartG]

footnote said:

I think it's true that most journalists know little about science (also statistics and finance)

Quite a few of them appear to know little about spelling and grammar either

[footnote]

MartG said:

footnote said:

I think it's true that most journalists know little about science (also statistics and finance)

Quite a few of them appear to know little about spelling and grammar either

I think there's an issue there in differentiating between qualified journalists and people who have a media presence but may not be trained but as you'll already know, a knowledge of spelling and grammar is no longer deemed essential for many people these days.

My favourite science story on R4, the one which nearly made me give up radio, was about some 'new discovery' and the scientist being interviewed was outlining a device which would or could somehow travel back in time and take photographs of the past - at least that's how it was presented in conversation with the journalist.

I was fascinated to know what would happen if they went back in time and photographed Christ.

I haven't heard any more about this great discovery - if anybody knows what it was, I'd love to know more. This was probably a couple of years ago when I heard about it. I don't think it's in the shops yet. But I suspect its capabilities may have been oversold somewhat.

Edited by footnote on Friday 24th November 17:03

[skeeterm5]

Einion Yrth said:

Only if the existence of such life is consistent with the physical laws of the universe; in an infinite universe, anything that is physically possible will occur an infinite number of times, nothing impossible ever will.

I don't know whether life not dependent upon water is possible, or not.

I am not sure that you can state that; in an infinite universe there must be room for the possibility of things that we consider "physically impossible" How are you defining impossible in this context?

I think that your argument demonstrates the common homo sapien centric view of the universe, a little like a modern day "the earth is at the centre of everything".

Edited by skeeterm5 on Friday 24th November 19:54

[skeeterm5]

Einion Yrth said:

Only if the existence of such life is consistent with the physical laws of the universe; in an infinite universe, anything that is physically possible will occur an infinite number of times, nothing impossible ever will.

I don't know whether life not dependent upon water is possible, or not.

double post

Edited by skeeterm5 on Friday 24th November 19:53

[Einion Yrth]

skeeterm5 said:

Einion Yrth said:

Only if the existence of such life is consistent with the physical laws of the universe; in an infinite universe, anything that is physically possible will occur an infinite number of times, nothing impossible ever will.

I don't know whether life not dependent upon water is possible, or not.

I am not sure that you can state that; in an infinite universe there must be room for the possibility of things that we consider "physically impossible" How are you defining impossible in this context?

I think that your argument demonstrates the common homo sapien centric view of the universe, a little like a modern day "the earth is at the centre of everything".

Edited by skeeterm5 on Friday 24th November 19:54

No, some things are possible, others are not; I do not presume to judge into which category any "unknown" thing falls. It does appear that the universe follows rules, if it doesn't then no prediction is possible, and if the universe obeys rules then some things will be impossible, infinity notwithstanding. What I believe has no bearing on these facts.
My definition of impossible is quite simple - anything that cannot happen given the laws that govern the universe (which I certainly don't know all of).

[ReverendCounter]

footnote said:

I haven't heard any more about this great discovery - if anybody knows what it was, I'd love to know more.

Was it something to do with a prediction that Einstein made relating to a device, which depended on tachyons, that he thought would enable time travelling images to be captured? Or summat?

[footnote]

ReverendCounter said:

footnote said:

I haven't heard any more about this great discovery - if anybody knows what it was, I'd love to know more.

Was it something to do with a prediction that Einstein made relating to a device, which depended on tachyons, that he thought would enable time travelling images to be captured? Or summat?

That sounds plausible!

It was very much a 'reality lite' type of report on R4 with a gushing scientist being whipped up by the presenter who sounded as if she believed this was going to be like a version of a camera on a long selfie-stick that could be passed along the 'Time Tunnel' back to whatever time you fancied.

I mean, it's a great idea when presented in that way but... well, who knows?

Maybe one day! I guess it's this kind of report that makes science sound exciting and appealing to some people and farcical to others.