New habitable planet discovered ?

[renormalised (Carl)]

Originally Posted by xelasnave

I feel I can out drivel anyone at thunderbolts
alex

I don't think so, Alex. They have driveling and dubious thought down to a very fine and specific art. Most are masters at it

[Sylvain (Jon)]

What we will see and learn in the process is going to open up so much to us and in the process of getting there, we will discover and invent things that we can't even begin to dream of today. That's why we need to take that first step, now.

This is so true! Just imagining all that we could discover...it's just beyond imagination! I would love to live in such an era!!! Let's hope (foolishly?) that it is to happen in the years to come.
I always hope that one of our radio-telescope will catch some kind of signal...it could change everything!

Fascinating thread by the way, thanks everyone!

[snas (Stuart)]

Also maybe what we consider to be habitable places an unnecessary restriction upon life as where we can expect to find it...maybe in other places is not so.

Alex, I agree. Since we are now touching on my area (biology) I feel I am somewhat qualified to pass comment. All the talk of planets in the habitable zone, presence of water, oxygen, carbon etc is all very well if you are searching for Earth-like life. But, as we have seen on Earth life has been found to flourish in "uninhabitable" locations such as in the superheated, high pressure water around volcanic vents in deep ocean and even flourishing in pools of sulphurous "magma". The bacteria found near volcanic vents are called thermophiles (heat loving) and have been shown via their DNA to be related to all other life on Earth via the "single common ancestor".

So if life can survive in such places, who is to say that life has to occur only in certain places, on certain types of planets. It is possible that life may be possible on a wide variety of planets, either Earth or Jupiter sized, with an Earth like atmosphere or a Jovian etc etc etc like atmosphere, close to a sun-like star or farther away from a very different star.

However the current research on thermophiles indicates that they probably adapted to life in their current environments, rather than being the "original" life form themselves. If this is true, then maybe life is required to form on an Earth like planet before it can gradually evolve to life such as thermophiles.

Paul Davies (Arizona State University) has (or maybe by now that should be had??) a theory (or perhaps hypothesis would be more correct) that life on Earth developed and was wiped out on several occasions during the 'early period of heavy bombardment.

The suggestions that follow on from this is that, if life did form on Earth on several separate occasions then:

1. Life WILL form if it is at all possible for it do so.
and therefore
2. Life MUST exist elsewhere in the Universe.

Again, these are suggestions, but the point is that if something so apparently unlikely can happen several times over on one planet, then the drive for life to form from abiotic substrates would appear to be so strong as to make life almost a certainty. Or....would it???

The converse of this is that, if life did only form on Earth once, then maybe we truly are alone.

Or......are we?

Stuart

[xelasnave]

Sometimes I like to indulge my imagination with things folk dismiss as impossible and on one of those times I imagined that there could be very very intelligent life on Mars... so intelligent that after years of technical and industrial development they realized to save themselves they had to take all the remaining water and atmosphere under the surface of the planet. so maybe such could be so..what the mind can conceive always has a chance at being a reality I like to think...and of course all life on Earth does similar in so far as it will adapt to the conditions available...now being surface dwellers we perhaps find such a prospect unreasonable. Anyways it would be funny if one of the Mars landers fell down a ventilation shaft and into a subterranean civilization more advanced than us.... mmm now would that not be a great movie plot.

I think the DNA thing is extraordinary and for me suggests that life will probably be everywhere in the universe...it is the universal floor plan and with it life can build whatever body it needs to fit certainly anything available on Earth and I suspect any place out there really...well maybe not the Sun but who knows for sure.

alex

[adman (Adam)]

Originally Posted by Jay-qu

No need to wait for FTL drives Renormalised, we just need to hit 1g sustained acceleration.

By my calculations, a trip to Gliese 581 (20light years) should take ~5 years (due to relativistic time dilation), though in Earth time it would be more like ~22 years. So a round trip, while only taking 10 years (+time to explore) will return you 44 years after you left..

can I just back up a few paces here - how fast would you be going if you accelerated at 1g for 5 years (or is that 22 years?)? And how the hell do you slow yourself from this velocity to a safe landing velocity?

I think you might make a good projectile like the one that kicked up all that water on the moon! At least the resulting spray might give us some good data about the composition of the planet - although you would have to make allowances for the organic matter of the unlucky astronauts.....

Seriously though - there seems to be a lot of thought given to acheiving a high velocity to shorten the trip, but little consideration of how to stop at the other end. What are the options for slowing a spacecraft?

Adam

[snas (Stuart)]

I think the DNA thing is extraordinary and for me suggests that life will probably be everywhere in the universe...it is the universal floor plan and with it life can build whatever body it needs to fit certainly anything available on Earth and I suspect any place out there really...well maybe not the Sun but who knows for sure.

Alex,

I think it's pretty fair to say that any compounds required for life are not going to do to well on or in the sun.

But then, ........

Regards
Stuart

[CraigS]

The existence of Gliese 581g is disputed !

Doubt cast on existence of habitable alien world

Last month, astronomers announced the discovery of the first potentially habitable extrasolar planet. But this week at an International Astronomical Union meeting, doubts were raised about the existence of this exciting new planet said to be orbiting the star Gliese 581.
…
“Simulations on the real data have shown that the probability that such a signal is just produced 'by chance' out of the noise is not negligible, of the order of several percents,” Pepe said. “Under these conditions we cannot confirm the presence of the announced planet Gliese 581 g.”

The 'f' planet is disputed as well:

“We haven't made a detailed analysis yet, but at first glance no statistically significant signal [for planet f] is emerging from our data set,”

Have we been manipulated by the media, yet again ?

Cheers

[mswhin63 (Malcolm)]

Somewhat of a chance, but could be someone jumping the gun, getting all excited.

[drsimmo (Simon)]

Tricky situation... one thing that is definitely true is that multi-planet systems are very hard to find and confirm. A fair bit more debate about these planets to come I suspect.

Also, a disclaimer: I collaborate with Paul Butler and Steve Vogt, but not on this particular system.