Do you think we will discover life somewhere other than earth in my lifetime?

Started by Curt, June 29, 2017, 06:19:08 AM

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xSilverPhinx

Yes, we are mesophiles, which means we like to live in medium conditions. I think my favourite extremophile (which live in extreme conditions) would the the hyperthermophiles, mostly Archea and some strains of bacteria who thrive in temperatures ranging from ~ 60 to 100 degrees Celsius.

In biotechnology some of their enzymes are used in PCR because they can stand such high temperatures.
I am what survives if it's slain - Zack Hemsey


Dave

Quote from: xSilverPhinx on June 29, 2017, 05:34:22 PM
Quote from: Gloucester on June 29, 2017, 06:50:55 AM
I look forward to hearing an oxygen rich atmosphere has been found on another planet - an almost certain indicator of life.

Is it? :notsure:

If a planet is so close to it's star then it could be heavily radiated with ultraviolet light, which breaks water (relatively abundant in the universe) into oxygen and hydrogen. Planets may exist where hydrogen, with less mass than oxygen, can escape an atmosphere but the oxygen can't, leaving an oxygen-rich atmosphere but with no life.

Also, when simple life arose on planet Earth they were most likely oxygen-intolerant anaerobes. O2 is such a vicious molecule that it takes a bit of evolving in order to deal with it, and even so, it eventually gets the best of us.

As Tank said oxygen is very reactive and, in our current models, needs plant life to repleish it.

Your heavily UV irradiated planet, Silver, would surely have to be so far out of the "Goldilocks zone" for that particukar star that life (as we know it, Jim) would be pretty unlikely. But, since UV seems to be highly mutagenic and light is the energy driving photosynthesis . . . .

But supposing there is high IR as well, or does this star radiate "cool'" UV only? Hmm, high UV star further away?  So the other factors, if measurable, would mitigate against deciding life was present.

Speculation is the enemy of sleep! Too bloody early!
Tomorrow is precious, don't ruin it by fouling up today.
Passed Monday 10th Dec 2018 age 74

xSilverPhinx

Quote from: Gloucester on July 01, 2017, 06:41:58 AM
As Tank said oxygen is very reactive and, in our current models, needs plant life to repleish it.

The problem with extrapolating what we know is that it's just a sample of one (planet Earth). In any other field that would be  statistical nightmare.

QuoteYour heavily UV irradiated planet, Silver, would surely have to be so far out of the "Goldilocks zone" for that particukar star that life (as we know it, Jim) would be pretty unlikely. But, since UV seems to be highly mutagenic and light is the energy driving photosynthesis . . . .

So what if it's out of the Goldilocks zone?  :P Take Jupiter's moon Europa, for instance, it's speculated that there could be simple life below its ice sheets due to the gravitational heating that Jupiter provides, even if it's outside our habitable zone.

It's not just UV radiation that ionises molecules. A magnetosphere could direct charged particles into a planet's or orbiting moon's atmosphere and that could be the source of oxygen in the atmosphere, such is the case with Saturn's moon Rhea and Jupiter's moons Europa and Ganymede.

While it's true that ionising radiation does destroy molecules such as DNA there are lifeforms that can resist such processes, such as the extremophile Deinococcus radiodurans. Maybe if somehow life got jumpstarted on another planet and managed to evolve into something resistant it could have resulted in an organism that could survive such high UV radiation. 

:notsure: As far as I know plant life on Earth does not use UV radiation for photosynthesis...they use mostly wavelengths corresponding to red and blue light.

QuoteBut supposing there is high IR as well, or does this star radiate "cool'" UV only? Hmm, high UV star further away?  So the other factors, if measurable, would mitigate against deciding life was present.

Speculation is the enemy of sleep! Too bloody early!

Yes, it's too early for this! It's not even 4 in the morning yet! :P
I am what survives if it's slain - Zack Hemsey


Dave

Silcer said:
QuoteSo what if it's out of the Goldilocks zone?  :P Take Jupiter's moon Europa, for instance, it's speculated that there could be simple life below its ice sheets due to the gravitational heating that Jupiter provides, even if it's outside our habitable zone.

Hmm, but taking a "cold" body and warming it, by whatever means, untill we think life might be possible seems more likely than its possibility on a heavily irradiated one to me. But then...

OK, we are working on a definition of conditions required for life that fit our current understanding - which has been stretched somewhar from that of a hundred years ago!

Yes, forgot thst UV is not used in photosynthesis, but it is a very energetic form of radiation in terms of a star's long distance output for creating chemical change. As with splitting water rather than merely vaporising it!

And I suppose that energetic radiation is energetic radiation, no matter its source, nature or wave-length!

http://photobiology.info/Albarracin.html
Tomorrow is precious, don't ruin it by fouling up today.
Passed Monday 10th Dec 2018 age 74


Arturo

I would "like" for life to be discovered elsewhere than our planet, but that doesn't mean it will happen. A very unlikely circumstance is we explore the entirety of the universe, finding that we are alone.
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No one

I am going to wholeheartedly disagree with that, the universe is far too large for humans to be alone. 

Arturo

Quote from: No one on July 08, 2017, 05:47:57 PM
I am going to wholeheartedly disagree with that, the universe is far too large for humans to be alone.

It's unlikely for humans to be alone according to the Fermi Paradox->
Yet we found nothing.

People said Trump would never be elected, look at where we are now...
It's Okay To Say You're Welcome
     Just let people be themselves.
     Arturo The1  リ壱

No one

Hence the enormity of the universe. The distances are fantastically vast. Our nearest star other than the sun,  is 4.3 light years away. And there are roughly 70 billion trillion other stars out there. Earth can not be the only planet with life.

Arturo

Quote from: No one on July 08, 2017, 08:27:05 PM
Hence the enormity of the universe. The distances are fantastically vast. Our nearest star other than the sun,  is 4.3 light years away. And there are roughly 70 billion trillion other stars out there. Earth can not be the only planet with life.

I'm not saying there aren't. I never said that. All I was saying is if that somehow it was empty, that would be disappointing.
It's Okay To Say You're Welcome
     Just let people be themselves.
     Arturo The1  リ壱

No one


Arturo

It's Okay To Say You're Welcome
     Just let people be themselves.
     Arturo The1  リ壱

Old Seer

I don't think so. Bee-ing a physicist I'd say highly unlikely but possible you'd be around. I'm sure they're out there but the distance is to great. I was thinking of this just the other day coincidentally.
I based my reply on the vastness of the universe. I thought of --if (in my opinion) they came into existence around the same time we did, and considering the speed of electromagnets at the speed of light, and if it hasn't gotten here as yet, they would have to be a very long way from here. In this case it would of course, depend upon the rate of evolution they developed under. The change you have being here my be minimal, and as it is the distance has already proven the be very very great between us. But, there's no exact telling and I'm sure you already understood that. You can calculate how far the magnetics would have to be from here to reach in time for when you are still here.
The speed of light times this, that and the other. If picking a time in history, IE 10000 bc to now, how long would it take for their  radio waves to be here. But, evolution can take millions of years.
The only thing possible the world needs saving from are the ones running it.
Oh lord, save us from those wanting to save us.
I'm not a Theist.

Old Seer

Quote from: No one on June 29, 2017, 04:38:08 PM
Well,  life is extremely unpredictable and can end in the blink of an eye. So, anyone's lifetime can end in the next few seconds, which almost certainly ensures that life outside of earth would not be discovered in said lifetime.

Also, alien life be discovered, and that discovery being disclosed to the general population, are two entirety different things.
Wow, I didn't think of that. They could have been and already blew themselves to smithereens. But they're radio waves would still be on the way.
The only thing possible the world needs saving from are the ones running it.
Oh lord, save us from those wanting to save us.
I'm not a Theist.

Arturo

Also something that crossed my mind - how do we even know they evolve? What if they just came into existence and stayed that way??? We could be sending messages to an alien version of a bacteria. Because I mean there is no guarantee that they have sex so how could they evolve??
It's Okay To Say You're Welcome
     Just let people be themselves.
     Arturo The1  リ壱