Astronomer "100% certain" of life on exoplanet

[Eldritch]

Alien life certain to exist on Earth-like planet, scientists say

The chances of alien life existing on a newly-discovered Earth-like planet are 100 per cent, an astronomer has claimed.

Gliese 581g was discovered orbiting a nearby star at a distance that places it squarely in the "habitable zone" where liquid could exist on its surface. Of around 500 planets that astronomers have found outside Earth's solar system, this is the first to be considered habitable.

The planet is a similar size to Earth and its mass indicates that it is probably rocky with a definite surface and has enough gravity to hold an atmosphere, according to Prof Steven Vogt, who led the team that discovered it.

It is as yet unknown whether water does exist on the planet or what kind of atmosphere it has. But because conditions are ideal for liquid, which is always a precursor for life on Earth, Prof Vogt believes that life will undoubtedly have begun there.

"Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent," he said during a press briefing. "I have almost no doubt about it."

The findings are based on 11 years of observations by ground-based telescopes at the W. M. Keck Observatory in Hawaii.

The close proximity of Gliese 581g and the fact that it was found relatively early in the astronomers' search suggests that there may be billions of other habitable planets like Earth in the universe.

Prof Vogt estimates that as many as one in five to 10 stars in the universe have planets that are Earth-sized and in the habitable zone.

With an estimated 200 billion stars in the galaxy, that means that around 40 billion planets could have the potential for life, he said.

The new findings by Prof Vogt and Paul Butler, of the Carnegie Institution in Washington, will be published in the Astrophysical Journal.

The paper reports the discovery of two new planets around the nearby red dwarf star Gliese 581.

The most interesting of the two new planets is Gliese 581g, which has a mass three to four times that of Earth and an orbital period of just under 37 days.

Gliese 581g is located 20 light years away from Earth in the constellation Libra.

The planet is tidally locked to the star, meaning that one side is always facing the star and basking in perpetual daylight, while the side facing away from the star is in perpetual darkness.

The researchers estimate that the average surface temperature of the planet is between -24 and 10 degrees Fahrenheit (-31 to -12 degrees Celsius).

Actual temperatures would range from blazing hot on the side facing the star to freezing cold on the dark side.

The surface gravity would be about the same or slightly higher than Earth's, so that a person could easily walk upright on the planet, Prof Vogt said.

Link. (http://www.telegraph.co.uk/science/space/8033930/Alien-life-certain-to-exist-on-Earth-like-planet-scientists-say.html)

Right. Prof. Vogt is not sure if this planet has water in liquid form, or what kind of an athosphere it has, but he is 100% sure there is life on it. :rolleyes2:

[Saruman]

It is atm very difficult to find such a proof, and it's not relevant for as long as stars are unreachable, but I'd say it's extremely probable that there is life somewhere. Most who doubt that are some religious people as in most religions Earth is center of the entire universe.

[Cato]

Alien life does not mean intelligent alien life or even complex non-intelligent alien life.

[Saruman]

Alien life does not mean intelligent alien life or even complex non-intelligent alien life.

No but it could. Consider how big space is, how many planets with potential similar conditions to earth alone, it quite likely that the life exists elsewhere. Of course the ultimate skeptic will require a proof, however currently one cannot prove that there is no extra-terrestrial life, as simply technology blocks us from checking any non-solar system, or even few moons in our system where some have speculated that life might exist. So the discussion is not relevant, firstly we need to advance ourselves sufficiently to make inquiries.

[Wyn]

I must be the only person who isn't that concerned about "alien life" and so on. :shrug: I just don't find it that interesting.

[Beorn]

Zacharia Sitchen (http://en.wikipedia.org/wiki/Zecharia_Sitchin) and Austin are one step closer to Nirvana.

http://markc1.typepad.com/.a/6a00d83451bb2969e20120a545ddc8970c-800wi

[ikki]

well the "holy spirit" on religious paintings have to have come from somewhere (depicted as UFO:s), already since atleast 1400s.

[Loddfafner]

What the hell is a scientist doing making a claim of 100% certainty?

[Agrippa]

What the hell is a scientist doing making a claim of 100% certainty?

Absolute nonsense, he can't say that, even less so if reading:

The researchers estimate that the average surface temperature of the planet is between -24 and 10 degrees Fahrenheit (-31 to -12 degrees Celsius).

Actual temperatures would range from blazing hot on the side facing the star to freezing cold on the dark side.

Doesn't sound to me like it would be "ideal" for the development of life in any form. Possible? Sure.
Likely? I'm not sure.
Life is there with 100 percent certainty? For sure not.

I always "laugh" when I read such crap and then compare it to "studies" or "scientists", ideologists, authors and politicians, which claim that there "is no proof for race or racial differences", and of course no proof for "differences in intelligence".

If comparing the proofs for such biological facts with the absurd ideas of some scientists which want to make it desperately into the media, especially those from the UK are often of that kind, one can just ask whether they are mad and what kind of science they're actually practising.

Prostitutes for the mass media and establishment I guess.

On the other hand I think I know why they are so "excited", because it's the first planet which could be a "more serious candidate", so they just exaggerate things.

[Wulfhere]

He's right, of course. If the planet was "earth-like", it would have life. Because having life is the defining feature of earth. The question is, are there any earth-like planets out there?

[poiuytrewq0987]

He's right, of course. If the planet was "earth-like", it would have life. Because having life is the defining feature of earth. The question is, are there any earth-like planets out there?

It would be illogical to believe that the planet we inhabitant on is the only planet in the entire universe with habitable conditions.

[Wulfhere]

It would be illogical to believe that the planet we inhabitant on is the only planet in the entire universe with habitable conditions.

Why? We have precisely no evidence of any life out there, so the logical position is to assume there isn't any, until any evidence emerges.

[Tomasz]

Why? We have precisely no evidence of any life out there, so the logical position is to assume there isn't any, until any evidence emerges.

Yes but we must also remember that lack of proofs doesn't necessarily mean that something isn't true.

Example: police tries to arrest me and I say "you can't arrest me, I didn't commit any crime - nobody found any proof for it". It's obviously flawed thinking because I could commit crime, evidence could have just not been found yet.

As for this very case, I think this "astronomer" exaggerated thing a lot. Especially this fragment showing extremely varying temperatures. I wouldn't exclude the possibility of life forms being there, however it can be hardly called "100% certain" that life evolved there.

[Wulfhere]

Yes but we must also remember that lack of proofs doesn't necessarily mean that something isn't true.

Example: police tries to arrest me and I say "you can't arrest me, I didn't commit any crime - nobody found any proof for it". It's obviously flawed thinking because I could commit crime, evidence haven't just been found yet.

As for this very case, I think this "astronomer" exaggerated thing a lot. Especially this fragment showing extremely varying temperatures. I wouldn't exclude the possibility of life forms being there, however it can be hardly called "100% certain" that life evolved there.

The example I always use is of the football-sized chocolate asteroid orbiting between Neptune and Pluto. We have no proof that it doesn't exist, but that doesn't mean we are obliged to believe it does.

[Tomasz]

The example I always use is of the football-sized chocolate asteroid orbiting between Neptune and Pluto. We have no proof that it doesn't exist, but that doesn't mean we are obliged to believe it does.

Sure but I think that the existence of life on the other planet is much more possible than existence of this chocolate asteroid. :) If I wouldn't have any reason to believe there might be some life forms outside of Earth, I wouldn't bother even thinking about it. But there's a high probability that somewhere in the universe, there might be a life (not counting our planet).

[Eldritch]

The example I always use is of the football-sized chocolate asteroid orbiting between Neptune and Pluto. We have no proof that it doesn't exist, but that doesn't mean we are obliged to believe it does.

But ee do have proof that the Earth exists, and that other planets and solar systems exist. Therefore it is perfectly reasonable to speculate on the probabilities of other Earth-like planets existing.


What the hell is a scientist doing making a claim of 100% certainty?

Answer: an ex-scientist, currently a quack.

[Svanhild]

http://img193.imageshack.us/img193/7886/nerd1.gif
"Dad, my programm asks if life can be found on Giese 581b?"

http://static.tvtropes.org/pmwiki/pub/images/Mad_scientist.gif
"Yes my son! My experiment reveals that there's life on Giese 581. I'm almost 100% certain, the liquid tells me!"

[Germanicus]

I read about this in todays Daily Mail, in the article it was said that if we could travel one tenth the speed of light we could reach the planet in 200 years:eek:

[Psychonaut]

Why? We have precisely no evidence of any life out there, so the logical position is to assume there isn't any, until any evidence emerges.

No.

Absence of evidence is not necessarily (http://en.wikipedia.org/wiki/Argument_from_ignorance#Distinguishing_Absence_of_ evidence_from_Evidence_of_absence) evidence of absence. And, in a situation like this, where less than a fraction of a percent of the cosmos has been observed, the latter certainly doesn't follow from the former.

[Loki]

His 100% certainty is not so far-fetched as it would first appear ...

http://www.bbc.co.uk/news/science-environment-11444022



Dr Vogt agreed: "The number of systems with potentially habitable planets is probably on the order of 10 or 20%, and when you multiply that by the hundreds of billions of stars in the Milky Way, that's a large number," he said.

"There could be tens of billions of these systems in our galaxy."


Now ... this is in a single galaxy, the Milky Way. There are probably more than (http://en.wikipedia.org/wiki/Galaxies) 170 billion (1.7 × 1011) galaxies in the observable universe.

You'll likely end up with a probability of 99.999% followed by billions of 9 decimals. That's pretty close to 100% I'd say. For all practical purposes it is. So, I agree with him.

EDIT: I realise he is talking about the one specific planet. In that case, yes he is exaggerating and jumping to conclusions of certainty too soon.

[Grumpy Cat]

I hope there's a Tim Hortons on that planet.

[Wulfhere]

No.

Absence of evidence is not necessarily (http://en.wikipedia.org/wiki/Argument_from_ignorance#Distinguishing_Absence_of_ evidence_from_Evidence_of_absence) evidence of absence. And, in a situation like this, where less than a fraction of a percent of the cosmos has been observed, the latter certainly doesn't follow from the former.

Absence of evidence is evidence of absence.

[Eldritch]

Absence of evidence is evidence of absence.

Nigga what ?!?

One would think that even with no training in formal logic, anyone would be able to deduct that they are not the same thing, since "absence" and "evidence" are not synonymous.


Absence of Evidence is a condition where no valid conclusion can be inferred from the mere absence of detection, normally due to doubt in the detection method.

Evidence of absence is the successful variation: a conclusion that relies on specific knowledge in conjunction with negative detection to deduce the absence of something. An example of evidence of absence is checking your pockets for spare change and finding nothing but being confident that the search would have found it if it was there.

[Wulfhere]

Nigga what ?!?

One would think that even with no training in formal logic, anyone would be able to deduct that they are not the same thing, since "absence" and "evidence" are not synonymous.

We're not talking about "formal logic", or the ridiculous example you used. If, after reasonable investigation, there is no evidence for something, then that is evidence (not proof) of absence.

Use your common sense.

[Eldritch]

We're not talking about "formal logic", or the ridiculous example you used.

You'd rather talk about chocolate Easter eggs floating around Pluto then?


If, after reasonable investigation, there is no evidence for something, then that is evidence (not proof) of absence.


Where did that "reasonable investigation" bit come from all of a sudden?

[Loddfafner]

Considering that it is not all that clear that intelligent life exists on earth, why should we expect it anywhere else?

[Stygian Cellarius]

Gliese 581g was discovered orbiting a nearby star at a distance that places it squarely in the "habitable zone" where liquid could exist on its surface. Of around 500 planets that astronomers have found outside Earth's solar system, this is the first to be considered habitable.

1/500, not bad.


"Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent," he said during a press briefing. "I have almost no doubt about it."

I think he makes it clear that he is aware how claims of one-hundred percent sound. That is why he made a point to include that a variable in his belief are his "personal feelings". This would make his statement something like this:

Translation: Based on science, life on Gliese 581g is highly probable, viz. the conditions required for life and the conditions of this planet match, bringing probablity to ~75%. However, scientific probability is not completely aligned with my intuition/feeling/heart/gut. Given my cathexis as an astronomer, there is no ~25% doubt registering in my personal feelings (feelings don't work that way anyhow), thus my emotions register positive for life on Gliese 581g and when translated into a number, that number would be 100%.

If he was asked: What are the chances of life on Gliese 581g? And was prohibited from altering the question by offering his "personal feeling" in response. He would have probably given a different answer.


The close proximity of Gliese 581g and the fact that it was found relatively early in the astronomers' search suggests that there may be billions of other habitable planets like Earth in the universe.

I betcha there are.


Prof Vogt estimates that as many as one in five to 10 stars in the universe have planets that are Earth-sized and in the habitable zone.

I don't really doubt this, but I wonder what that is based on because they just said that only 1 in 500 Planets thus far are considered habitable.

Also, I wonder why they spelled out "one and five", but wrote the number "10"? hmm :shrug:


Gliese 581g is located 20 light years away from Earth in the constellation Libra.

That is not that far at all. When can I pack my bags?


The researchers estimate that the average surface temperature of the planet is between -24 and 10 degrees Fahrenheit (-31 to -12 degrees Celsius).

Useless information.


The planet is tidally locked to the star, meaning that one side is always facing the star and basking in perpetual daylight, while the side facing away from the star is in perpetual darkness.


Actual temperatures would range from blazing hot on the side facing the star to freezing cold on the dark side.

Okay, cool, so there is a belt around the Planet inbetween the two that is a perpetual Eden. Pick your temperature of choice fellows and migrate to that belt.

I would imagine that the temperature differential would create "pressure void" on one side of the Planet that the higher pressure side would constantly fill = high winds, circulating heat around the Planet. Which would warm up the "freezing" side and vice versa.

[Wulfhere]

You'd rather talk about chocolate Easter eggs floating around Pluto then?



Where did that "reasonable investigation" bit come from all of a sudden?

Reasonable investigation is what you would have to perform in order to talk about any evidence at all.

[Guapo]

well the "holy spirit" on religious paintings have to have come from somewhere (depicted as UFO:s), already since atleast 1400s.

gSp1zUkJSfo

[Wulfhere]

Also, I wonder why they spelled out "one and five", but wrote the number "10"? hmm :shrug:


Because standard practice in English, at least with regard to newspapers, is to spell out one to seven, but use the numeral from 8 upwards.

[Eldritch]

Reasonable investigation is what you would have to perform in order to talk about any evidence at all.

Or its absence. But what I actually asked was how come you chose to introduce the concept into the discussion at this point in the first place.

Remember that you said "absence of evidence is evidence of absence", and not "absence of evidence after reasonable investigation is evidence of absence".

[Wulfhere]

Or its absence. But what I actually asked was how come you chose to introduce the concept into the discussion at this point in the first place.

Remember that you said "absence of evidence is evidence of absence", and not "absence of evidence after reasonable investigation is evidence of absence".

Indeed. Without actually bothering to check, it cannot be said that there's an absence of evidence.

[Liffrea]

Mathematically it is improbable that earth is the only life bearing planet in the universe.

Personally I expect life to be common but I’m less convinced that intelligent life is all that common or if it is then perhaps its survival rates are not at all high. 20ly isn’t far astronomically a space faring civilisation capable of a tenth of the speed of light (we could probably have the technology within a couple of hundred years) could cover that in 200 years or so.

I think our putative friends on Gliese 581g would have to be less advanced than us, long dead, so advanced to be beyond our thought or (more likely) never there in the first place. Human colonists (more likely post-humans) will probably find bugs, diseases (interesting to speculate if and how alien bacteria would affect humans, different ecosystems they have evolved in…) and not much else. Perhaps the ruins of a long dead civilisation, maybe one of our star farers could be of a poetic mind. Worse for them if they only have bows and we have laser cannons, natural selection is both beautiful and cruel, of course they could be on their way here with a death star…..

[ikki]

Guapo, more like this:

http://www.crystalinks.com/ufojesus2.jpg
http://www.crystalinks.com/ufomaryhead1.jpg
http://www.crystalinks.com/ufosummer.jpg

amongst those a bit harder to explain away.

[Norse Sword]

There are galaxies that contain 3 trillion stars. There are possibly 500 billion galaxies. That is allot of chances for life to happen in the same way it happened here, no matter what your personal reflection of creation would be.
Only a total buffoon would bet against those odds.

I doubt a God would waste such a Immense space on just us. That would be about the most arrogant thing a being could say.

This scientist is a moron though. It is possible the atmosphere on those planets is extremely toxic to all life forms as we know them.

Unless there is a profound acceleration of technology, none alive today will witness the landing of a Human spacecraft on a distant habitable planet.
Indeed, you would assume if space travel between habitable worlds is possible by intelligent life, we would have had verifiable proof of such visitations within at least the last 10,000 years.


If it did occur, then it may even take radically advanced life forms,many thousands of years to go between star systems.

The vacuum of space, and distances involved, are a incredibly efficient barrier for space travel, especially for frail life forms such as ourselves. If there are "Aliens" traveling space, they most likely are in a form that does not succumb to the extreme number of physical limitations that prevent us from migrating to the stars.


If life happened here, and attune to evolutionary concepts, If it only takes the formation of liquid water, a radiation barricaded atmosphere, and simple formation of amino acids to begin formation of self replicating life, it is CERTAIN to have happened elsewhere.

However, seeing there has only been one form of life here on earth that we know of, that can even claim to have stepped into space, the ability to do so, over interstellar distances may be extremely rare, if at all for intelligent, carbon based life forms. At any rate, we may NEVER know if other planets are
habitable, some things may ALWAYS remain out of our reach, simply by the form humans take.

[Psychonaut]

If there are "Aliens" traveling space, they most likely are in a form that does not succumb to the extreme number of physical limitations that prevent us from migrating to the stars.

Heaven help us if there's a larger version of something out there like our own water bears (http://en.wikipedia.org/wiki/Water_Bears) that can survive in any and all environments including the vacuum of space:

http://www.wired.com/images_blogs/wiredscience/images/2008/09/08/tardigrade3.jpg

[Norse Sword]

I must be the only person who isn't that concerned about "alien life" and so on. :shrug: I just don't find it that interesting.

You would be really concerned if Aliens landed tomorrow.


Stephen Hawking suggests that we should avoid contact with alien life, simply because it is most likely the same reason, what we would do if human kind traveled to a distant planet, and found it occupied by a primitive life form.

We would end up with space monkeys in our zoos. The same may happen to us if such a extremely advanced alien race landed here!

Personally, I would not want anyone getting probed like those alien abduction people! :thumb001::thumb001::thumb001:

[Norse Sword]

Heaven help us if there's a larger version of something out there like our own water bears (http://en.wikipedia.org/wiki/Water_Bears) that can survive in any and all environments including the vacuum of space:

http://www.wired.com/images_blogs/wiredscience/images/2008/09/08/tardigrade3.jpg

Like I said, a Intelligent life form that can travel interstellar space, will most likely be something far removed from ourselves.

I just hope they don't eat carbon based life forms.

WATER BEARS, they could be your great great grandfather to the 25th power.

[Stygian Cellarius]

Heaven help us if there's a larger version of something out there like our own water bears (http://en.wikipedia.org/wiki/Water_Bears) that can survive in any and all environments including the vacuum of space:

http://www.wired.com/images_blogs/wiredscience/images/2008/09/08/tardigrade3.jpg

Heaven help us? I just wanna give that thing a hug! :p

So that's the little feller they sent in space? I didn't know he/she looked like that. Gives me a good idea for a new stuffed animal though, Water Huggy Bears.

[Svipdag]

This astronomer is banking very heavily on the exobiologists' fundamental article of faith:that, given suitable physical and chemical conditions,life will inevitably arise. There is not a shred of evidence that this is true.

It is a statement of faith, not of fact. Evidently, this astronomer shares in their faith. I don't care what he BELIEVES. What are the FACTS ? The facts indicate that there is a narrow transitional zone between the light and dark hemispheres of Gliese 581g in which life could survive.

THIS PROVES NOTHING . It does not, in the absence of other evidence,
indicate that there IS life in that zone or that life has actually originated
in that zone. This man's assertion that he is "100% certain" that there is life on Gliese 518g means only that he BELIEVES that there is life there. and his
"certainty" is based on nothing but irresponsible speculation.

It is interesting that conditions on part of Gliese 518g PERMIT the existence
of life there.Now, where and what is the evidence that it DOES exist there ?

[Liffrea]

Originally Posted by Norse Sword
Stephen Hawking suggests that we should avoid contact with alien life, simply because it is most likely the same reason, what we would do if human kind traveled to a distant planet, and found it occupied by a primitive life form.

The laws of physics apply everywhere in the observable universe, it isn’t illogical to presume that the laws of life do as well.

If that is the case Hawking is correct in my opinion. Any species will expand unless prevented and will do so at the expense of other forms, here on earth man is the most successful form of life, like it or not many species are now on borrowed time (perhaps including humanity).

One of the reasons I’m sceptical about alien intelligence is because we are still here. Ten billion years is a long time, someone should have colonised the galaxy by now.