Talk:Extraterrestrial life

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Fact: no extrateresstial life found[edit]

I took off some apparent vandalism: "Aliens have been found hovering over the skies of africa, asia, and europe. They have attacked about 10 people and are on their way to australia..."


I missed a simple statement right at the beginning that until today there has been no scientific proof for et-life. Better also add the fact that some extreme local life forms found can be traced back to earth-life. What is the purpose of the whole article if it doesn't state anywhere if the topic has been found or not. Crass Spektakel (talk) 08:42, 17 June 2011 (UTC)

The third sentence addresses this: It is currently unknown whether any such forms of life exist or ever existed. Barnabypage (talk) 11:20, 17 June 2011 (UTC)

I added this back in, I think it's important. Kaspuhler (talk) 21:09, 18 July 2011 (UTC)kaspuhler

Actually NASA found alien bacteria fossils in one martian rock they have found.Well that was one proof but not so big at all. — Preceding unsigned comment added by Elaizaleen (talkcontribs) 11:27, 15 February 2012 (UTC)
Unlikely. Please provide a link. Rwessel (talk) 23:50, 15 February 2012 (UTC)
You must be referring to the ALH84001 meteorite, and the scientific consensus is that there was no bacterial fossils in it. Cheers, BatteryIncluded (talk) 16:29, 21 February 2012 (UTC)

Extraterrestrial life isn't necessarily the only thing called aliens y'know. Humanity are aliens. Alien is not a race is a description of something of an unknown origin, with an unknown cultural and unknown name. So I think alien should be removed as a second name. Because it looks like it points out that humans in this sentence "It is often also referred to as alien life, or simply aliens (or space aliens, to differentiate from other definitions of alien or aliens). These hypothetical forms of life range from simple bacteria-like organisms to beings far more complex than humans." are hypothecial forms and that we are bacteria-like organisms.--03:51, 3 March 2013 (UTC) — Preceding unsigned comment added by 58.164.136.30 (talk)

ALH84001 reserach remains inconclusive, albeit the evidence so far leans heavily to a biogenic explaination. That is very different from "no fossils", it means "looks like fossils, but we are not entirely sure". In addition to that there is the paper from Richard Hoover, from which NASA distanced itself. He was ridiculed in the media but i have still to come across a study wich conclusivly dismissed the points raised by Hoover. In addition to that there is the spectroscopy research on cosmic dust by Hoyle and Wickramasinghe, that latter recently working together with Hoover to produce the highly controversal paper on the Polonaruwa meteorite. Then there is the work of Gilbert Levin, the engineer deigning the Labled Release Experiment for the Viking probes, who, to this day, remains convinced the gathered data points to an active metabolism in martian soil. These claims have only been bolstered in the recent years, namely by discovering that Mars possesed a magnetic field in ancient times, as well as recently the indentivication of ancient riverbeds by the Curiosity rover. Even NASA now officially proclaimed Mars being a habitable world in the past - habitable in the meaning as habitable for humans, not unlike Earth today. In addition to that the findings that certain microbes can survive space conditions during tests performed abourd the ISS and possibly remain viable for billions of years, potentially being capable to reach other star systems in VIABLE form are staggering, to say at least. All subsequent studies, such as impact and reentry tests suppotrt this scenario. Albeit all those claims are not totally conclusive evidence is mounting in favour of a biosphere exceeding planetary, if not solar boundaries. Fossilized filament mats with carbonate cores are very hard to explain by abiotic causes. So arguably, depending on your position in this debate, there IS evidence. The question is merely if there is ENOUGH evidence to cause a paradigm shift.

217.89.117.154 (talk) 09:18, 18 April 2013 (UTC)

Arsenic-based life in Mono Lake, US[edit]

Recent discovery of arsenic-based life in Mono Lake, US; suggests an earth-based life form inconsisent with other forms of life - a possible "life 2.0" candidate. Apologies for lack of formatting.

There's been no such claim. ALL life as we know it has been based on carbon. HammerFilmFan (talk) 23:04, 4 September 2012 (UTC)

Why is this article very long?[edit]

Why not? It isn't that long compared to some other articles, and I'm not aware of any guideline saying "keep it short just to keep it short." Also, could you please leave more of a message than a new section title and sign your posts with four tidles (~~~~)? Ian.thomson (talk) 00:37, 30 March 2010 (UTC)
A long article for an important subject. It fits. --Againme (talk) 21:18, 5 May 2010 (UTC)

"Although no samples have been found"[edit]

What about that news conference when Bill Clinton was president? They found bacteria samples that were from Mars, didn't they? That seems like a sample. — Timneu22 · talk 12:08, 3 May 2010 (UTC)

I think you are refering to the Allan Hills 84001 meteorite. I'll edit the article so the reflect this. --Againme (talk) 16:01, 3 May 2010 (UTC)

They found stuff that might be alive (and also may have been of terrestrial origin) on a meteor from Mars. Whereas it is an intriguing sample you cannot call it a sample of extraterrestrial life until A LOT of testing is done (ie they won't ever confirm this one way or another). -kaspuhler — Preceding unsigned comment added by Kaspuhler (talkcontribs) 21:02, 18 July 2011 (UTC)

Lede image change requested[edit]

Is it possible to find a better image for the lede; one that illustrates the subject more clearly than a postage stamp? All is One (talk) 16:30, 28 May 2010 (UTC)

It might be that wikimedia commons hasn't a better image to represent the subject. I was surprised when I clicked on the image, that many wikis in other languages also use it. You can always propose a new one although I do like this image and its somewhat abstract representation of ET life. GaussianCopula (talk) 07:12, 29 May 2010 (UTC)
Yeah...the stamp pic is a little lame. SolarWind123 —Preceding unsigned comment added by SolarWind123 (talkcontribs) 21:39, 26 June 2010 (UTC)
About us not transmitting anything into deep space -- we do! We beam sounds and ligh pulses into deep space. The line about us not doing so is just plain wrong. —Preceding unsigned comment added by 121.127.201.138 (talk) 06:26, 21 July 2010 (UTC)
Plain wrong is an incorrect term. You should use the term "without exotic ingredients wrong" instead.96.49.102.179 (talk) 14:47, 23 October 2010 (UTC)
Agreed. A much better photo could be used for this page... Especially for a topic as huge as this one. (User: Daniellelynettehardy) —Preceding undated comment added 14:19, 28 September 2011 (UTC).

Yes check.svg Done! I've removed the fantasy Soviet stamp image and replaced it with a montage that's a visual summary of the current government/science consensus (no evidence yet) and the three major efforts in the search as outlined in the White House document Tom-b (talk) 17:14, 13 September 2012 (UTC)

Yes, the new lede image (& caption) seems much better - Thanks for your efforts - and - Enjoy! :) Drbogdan (talk) 18:44, 13 September 2012 (UTC)
Thanks! Tom-b (talk) 12:46, 14 September 2012 (UTC)

Lifeless moons[edit]

I'd like some comment on this diff. To me seems fairly obvious that the moons still appear lifeless, and will continue to appear like that until someone finds evidence of life on them. User:Kalidasa 777 modified in "initially appeared", implying that they now appear somehow inhabited. I don't want an edit war, so some comment would help. Thanks. --Cyclopiatalk 01:45, 15 June 2010 (UTC)

How do you suppose a world with microbial life would appear to a space probe flying by, or orbiting overhead, or landing without instruments specifically designed to search for organisms? Hasn't Titan, in particular, recently been yielding the sort of data (re levels of hydrogen, acetylene, ethane near the surface) that would be expected from a Titan-like world that does have life? No-one is saying this proves living things are there... but, does it now appear lifeless, or does it now appear possible for life? Kalidasa 777 (talk) 05:56, 19 July 2010 (UTC)

"Appear lifeless" means "there are no obvious signs of life". That's the case. No obvious signs: there are faint, remote clues. So they appear lifeless to all practical purposes. Note that "possible for life" and "appear lifeless" are not contradictory: the Atacama desert is possible for life, but it appears lifeless nonetheless. --Cyclopiatalk 10:42, 6 August 2010 (UTC)

Existence is the wrong question[edit]

Whether life exists in any other place is an unsophisticated question for a scientist. A better question would be what is the frequency or density of life in the universe. How often does it form? In how many forms does it form. We have a lot of data already, because we all agree that life exists in the universe, on Earth. The question of density already has an answer. We have life on Earth. If we discover life in other places, we will have even more data. The question of whether life exists is also already answered. To separate life on Earth from all other potential life is more religious than scientific. The question of existence will not have an answer until we find extraterrestrial life. If that happens then the answer will be yes, it exists, and the new question will be about frequency or density. Why wait? —Preceding unsigned comment added by 68.2.47.164 (talk) 07:50, 1 August 2010 (UTC)

1) New stuff goes at the bottom.
2) This is not a general discussion forum but a venue to discuss how to improve the article.
3) The article is not supposed to investigate questions, but simply report what is in sources. See the neutral point of view policy. It is also not supposed to speculate, see this section of the essay "What Wikipedia is not."
4) Please sign your posts in talk pages with four tildes (~~~~). Ian.thomson (talk) 17:48, 1 August 2010 (UTC)
The point raised in the unsigned comment above has to do with the way astrobiology is conceived, as explained on the page astrobiology. I've added a few words to this Extraterrestrial Life article, briefly clarifying that life on Earth (viewed in its astronomical context) is also within the field of astrobiology. Kalidasa 777 (talk) 03:45, 6 August 2010 (UTC)

Possible impact on Earth by extraterrestrial beings?[edit]

Sorry but this section is irrelevant. To me they are oppinions not fact. Maybe we should say it is Stephen Hawkings opinion? Steahl (talk) 20:46, 25 September 2010 (UTC)

Keep section. Suggest renaming it to avoid speculation. All is One (talk) 20:13, 27 September 2010 (UTC)
I'm for keeping it as well. Autumn Veil 07:45, 1 October 2010 (UTC) —Preceding unsigned comment added by Autumn Veil (talkcontribs)
I'm for keep but why is the section so short? I remember the PBS program NOVA having at least three separate episodes on how the world may react to knowledge that life exists off of earth (not even intelligent life..). There are books, newspaper articles, and religious commentary on the subject. Why do we only have one scientists opinion stated....or am I missing a link to the larger article? —Preceding unsigned comment added by 97.112.13.62 (talk) 16:39, 5 December 2010 (UTC)

Someone with write privileges, please add that life on earth can also be based on Arsenic; NASA recently discovered this: http://www.nasa.gov/home/hqnews/2010/dec/HQ_10-320_Toxic_Life.html —Preceding unsigned comment added by 24.161.73.14 (talk) 23:11, 12 December 2010 (UTC)

It has not been "discovered", it has been claimed as a result of a controversial experiment that some peers have harshly criticized, so we cannot yet state that life can be based on arsenic instead of phosphorus. -- Boing! said Zebedee (talk) 20:30, 28 February 2011 (UTC)

This article has just been published and outlines a number of possible scenarios: http://arxiv.org/ftp/arxiv/papers/1104/1104.4462.pdfTotorotroll (talk) 20:51, 18 August 2011 (UTC)

Requirements[edit]

Life on earth does not require carbon, oxygen, phosphorus and so on, that entire premise is as outdated as phrenology. Discuss removing or modifying it. 99.236.221.124 (talk) 01:53, 17 December 2010 (UTC)

Does it not? Please explain. -- Boing! said Zebedee (talk) 23:41, 22 January 2011 (UTC)
I think the person who started this thread meant life in the Universe, see Arsenic related threads. The point is that animate matter can arise in material evolution on a basis different from what has happened on the Earth. Life is simply animate matter, not animate matter life that which evolved here. A priori only a narrow anthropocentric viewpoint requires it to be carbon based because we happened to evolve from such a chain. Any active organization based on another element that climbs the stages of control metasystem transition from the first molecular combinations could lead to an alternate basis for "organic chemistry" and could evolve intelligent animals based on that chemistry, e.g. Arsenic, Silicon, etc. Those stages being: control of position - motion, control of motion - irritation, control of irritation - reflex, control of reflex - association, control of association - thought, control of thought - culture.

However, it's correct I think that the Arsenic using molecular phenomenon observed don't amount to such a line or even a basis for an alternative organic chemistry, so that those observations and conjecture/speculation that life could have taken that route here what should be cast as like phrenology.198.255.198.157 (talk) 11:46, 24 December 2013 (UTC)

Arsenic[edit]

I've reverted the addition of factual statements that those "arsenic bacteria" can use arsenic as a substitute for phosphorous. The claim has been made, but it's highly controversial, and some peer reviewers have criticized the experimental methods. Factual claims of its being a "discovery" are therefore way premature. -- Boing! said Zebedee (talk) 23:37, 22 January 2011 (UTC)

Edit request from 173.77.78.122, 14 February 2011[edit]

{{edit semi-protected}} The author of "Sefer HaBrit" (first published in Holland, 1797) is the eminent 18th century kabbalist, Rabbi Pinchas Eliyahu Horowitz of Vilna. This book was one of the primary sources for scientific knowledge among early 19th century Jewish religious scholars; encyclopedic in scope, it discusses the secular science of the author's day from a kabbalistic point of view in Part I, and outlines certain basics of Kabbalah, as well as the mystic's quest for Divine revelation in Part II.

(Perhaps this should be mentioned after citing the book as a Jewish work that mentions extraterrestrial life.)

173.77.78.122 (talk) 00:41, 14 February 2011 (UTC)

Not done: That information does not appear to be relevant to this article; here, all we are really concerned with is the books comments about extraterrestrials. Qwyrxian (talk) 14:06, 14 February 2011 (UTC)

NASA scientist finds evidence of alien life[edit]

Today's news. NASA scientist finds evidence of alien life and 72 news articles today. Have fun! CarolMooreDC (talk) 05:01, 6 March 2011 (UTC)

Added a related note & refs to the main article - entirely ok to improve wording, location, etc as needed of course - in any case - enjoy! :) Drbogdan (talk) 19:09, 6 March 2011 (UTC)

Who says Mercury might have life?[edit]

I was surprised to see Mercury in the list of bodies in the solar system which have been suggested as possibly having life. I checked the reference given. MESSENGER Scientists 'Astonished' to Find Water in Mercury's Thin Atmosphere It talks about "water-related ions" in the extremely tenuous atmosphere, and about possible reservoirs of water ice near the poles. But ions are charged molecules, and water molecules (charged or otherwise) don't necessarily say anything about life. As I understand it, liquid water is the stuff astrobiologists have in mind when they talk about "following the water" in the search for life; and I couldn't see any reference in the article to liquid water being a possibility on Mercury. Nor could I see any direct statement (one way or the other) about prospects of life there... If anyone can find a statement by a planetary scientist actually saying that Mercury might have life, then yes, great, include Mercury in the list... Otherwise, I have to say that this comes under the heading of Original Research by a Wikipedian. Kalidasa 777 (talk) 07:08, 16 April 2011 (UTC)

I'd like to see any such reference as well. I, for one, was under the understanding that Mercury was very similar to Earth's Moon, albeit somewhat more massive and orbiting the Sun independently. The Mysterious El Willstro (talk) 06:54, 18 May 2011 (UTC)

Minor correction[edit]

Mentions of finite (especially known and finite) numbers of anything in the whole Universe are never strictly speaking correct, because we have no way of knowing all of our continuum, which apparently is nearly Euclidean (which would provide infinite volume as per geometric laws) and if anything slightly parabolic rather than elliptical. So, any such mention of a total number of galaxies or galaxy clusters should be stated in terms of the Observable Universe, IE the part of the Universe that is close enough to Earth that light has had time to reach us already since the Bang. (Granted, the density of the Universe is apparently low enough to tend toward continued "expansion," reduction of density of the Universe even lower, if the Observable Universe is any guide at all.) The Observable Universe is the only part of the Universe about which we can know anything at all, so certainly it's what Hubble is showing. I've clarified this. The Mysterious El Willstro (talk) 07:07, 18 May 2011 (UTC)

Arecibo message[edit]

The arecibo message shown has a wrong caption. It talks about the attempt of human contact with aliens or something like that, but on the actual Arecibo message wiki article it talks about it actually being a way of showing the strengths of the technology they had. Please correct that. --Roflmaoshizmp (talk) 18:51, 6 June 2011 (UTC)

I think the former is a prerequisite for the latter. That is, your message first need to be received by the aliens before you can attempt to demonstrate your technological level. Hence, I don't the caption is incorrect as written. Regards, RJH (talk) 15:53, 9 August 2011 (UTC)

False assertion[edit]

The following statement appears to be a false assertion:

Because Earth and other planets are made up of "stardust"; that is, relatively abundant chemical elements formed in stars, it is very probable that other planets may have been formed by elements of a similar composition to the Earth's.

First, gas giants are primarily composed of hydrogen and helium, which are relatively scarce in the Earth. Hence, this statement can only be made with regards to terrestrial planets. Second, simulations show that there can exist a diverse range of terrestrial planet types:

Bond, Jade C.; O'Brien, David P.; Lauretta, Dante S. (June 2010). "The Compositional Diversity of Extrasolar Terrestrial Planets. I. In Situ Simulations". The Astrophysical Journal 715 (2): 1050–1070. Bibcode:2010ApJ...715.1050B. doi:10.1088/0004-637X/715/2/1050. 

Thus, many terrestrial planets may exist that do not have a similar composition to the Earth. I think the claim should be reworded. Any suggestions? Just stating that the terrestrial planets are made of star dust doesn't seem very useful. RJH (talk) 20:34, 8 August 2011 (UTC)

That paragraph and the next few appear to be original research... In the mean time, perhaps
Terrestrial planets, such as Earth, are formed from "stardust" in a process which allows for the possibility of other planets having formed with compositions similar to Earth's."
Seems to be what the author(s) were trying to say, but is clearer and doesn't appear to contradict the information you've cited. Ian.thomson (talk) 22:03, 8 August 2011 (UTC)
Yes, that should work. Thank you. Regards, RJH (talk) 22:06, 8 August 2011 (UTC)

additional article requests related to the topic[edit]

i think we need an article called "list of extra terrestrial life forms" because that way it will be a proper list a.k.a not fictional aliens i can't help though cause i'm doing other stuff but i still think it should happen Ace10000 (talk) 12:12, 20 August 2011 (UTC)

The list has been made: It is empty. It is accurate. BatteryIncluded (talk) 16:39, 21 February 2012 (UTC)

Overlap with astrobiology article[edit]

The division of content between this article and astrobiology seems a bit fuzzy to me. What is the intended rationale, if any? -- Beland (talk) 03:59, 22 August 2011 (UTC)

Agree, from what I can tell there are key differences though (although I agree, this article should redirect to astrobiology) All of the same topics are covered there, the only notable exceptions being:
  • Early philosphy of life elsewhere in the universe
  • UFOlogy and Conspiracy theories - Area 51, Roswell, Alien abduction and related pseudo-sciences. These are best kept to the UFO articles. The link to extraterrestrial life is a stretch, the realm of popular culture
  • Science Fiction (Orson Welles etc) also pop culture - film etc

The topic in my opinion is too broad, these pseudo-scientific and philosophical topics rub shoulders with scientific topics. Wikipedia is an encyclopedia, so in my opinion the topic of extraterrestrial life should be kept to its scientific study. --EvenGreenerFish (talk) 05:17, 15 November 2011 (UTC)

It's pretty broad, but where you put the material on beliefs and fiction and such if this article was turned into "Science of extraterrestrial life" or something like that? Dicklyon (talk) 06:10, 15 November 2011 (UTC)

Halo effect[edit]

While I don't necessarily object to its inclusion in the article, I fear that the few sentences mentioning the unsupportable conjecture of such perceived luminaries as Stephen Hawking and Jared Diamond gives undue weight to the negative side of the debate over the possible effects of extraterrestrial contact. As a physicist, Hawking is, to put it bluntly, simply out of his depth. His understanding of the fate of American Indians after contact with Europeans seems extremely shallow at best. Hawking isn't the only physicist or astronomer to make such comparisons, but most seem to be under the mistaken impression that native peoples and cultures were somehow destroyed as a result of these contacts. In fact, cultural persistence in the face of such adversity is nothing short of remarkable. Where and when peoples and cultures did die out, the did so as a result of disease, something which both humans and advanced alien lifeforms have a much more fundamental understanding of than fifteenth century Europeans or Indians. As for Diamond, as an anthropologist he would, at first blush, appear to be somewhat more credible regarding such an unanswerable scenario, but his notions of why various groups of New Guinea or pre-Columbian North America "failed" are similarly simplistic and ahistorical. Keep such information if you must, but better balance should be sought, lest the name-recognition value of Hawking or Diamond might lead people to believe that there is something approaching a consensus on the matter. To the stars, Shorbu!--172.191.0.104 (talk) 04:16, 7 October 2011 (UTC)

We can't travel to the stars in any time frame less than millenia, so please calm thyself; and if you think the cultures of North America "survived" the contact with white European civilization, think again. Oh, there are meager remnants, but for all intents and purposes those cultures were wiped away in both intentional and unintentional actions. You don't have to be a chicken to judge an egg, and Hawking is a bright enough man to ponder this issue and get respect for his beliefs. HammerFilmFan (talk) 23:12, 4 September 2012 (UTC)
Not sure how you ascertained my state of mind from that, but, regardless, the fact remains that Hawking's popular reputation as a physicist gives his opinions on this (and other matters, like, oh...God) undue weight. Why the hell would you want a chicken to judge an egg, anyway? Get an ornithologist, please, or at least someone that knows about chickens. Hawking is free to ruminate on anything he chooses, but it isn't safe to just assume that he knows what the hell he is talking about. Besides that, even if you're so-called "meager remnants" notion were true (which is debatable), it would be because of the aforementioned epidemic diseases, not because these cultures collectively curled up into a ball and shat themselves upon contact with a more advanced civilization, which is exactly the idea being professed here: not disease, not malice on the part of our new alien overlords, but the fact that our puny human pea-brains would not be able to comprehend a culture/race more advanced than we are. Thus, even if the historical examples of culture shock-induced decline were valid (which is, again, debatable) to extrapolate this into some great governing "law" for all time is inappropriate.--172.190.50.161 (talk) 03:30, 2 April 2013 (UTC)

Habitability vs. Inhabited and other Weasels[edit]

I feel strongly that the "Background" section (if not the whole article) needs a re-write as I perceive the use of some weasel wording (WP:Weasel) that distorts the original scientific meaning. One example is:

"Suggested locations at which life might have developed, or which might continue to host life today, include the planets Venus[5] and Mars, Jupiter's moon Europa,[6] and Saturn's moons Titan and Enceladus.[7] In May 2011, NASA scientists reported that Enceladus "is emerging as the most habitable spot beyond Earth in the Solar System for life as we know it".[8][9] Life may appear on extrasolar planets, such as Gliese 581 c, g and d, recently discovered to be near Earth mass and apparently located in their star's habitable zone, with the potential to have liquid water."

The Most obvious one is the incorrect use (and assumption) that habitability equals inhabited. Planetary habitability is the measure of a planet's or a natural satellite's potential to sustain life. That means that a planet can be habitable and be completely sterile.

The paragraph above also indicates that they might continue to host life. Continue? It was never determined they EVER hosted life al all. How can they "continue"? Regarding extrasolar planets, the same weasel wording is used. No scientist has published that "Life may appear on extrasolar planets". Experts are only starting to collect data on possible "habitability" or on environments friendly to host life (if it was introduced). The article goes on to mention "extraterrestrial objects" - That is a very wide statement. What is that?? Is it a StarTreck phaser handgun (inexistent) or meteorites (existent)?

These are just a couple of observations on many inaccuracies and weaseling in this article. I would spend time editing it for scientific accuracy but since we already have the Astrobiology article, it'd make this one redundant - if fixed. I am tempted to propose a merge with the Astrobiology article and move/merge all the assumptions (non-scientific material) and "beliefs" in an appropriately named article. What say you?BatteryIncluded (talk) 17:19, 21 February 2012 (UTC)

Don't we begin our search for in "habitable" places instead of "inhabitable" places? We are at that very opint right now: considered whether Life As We Know can exist on various bodies in our solar system, based on conditions found there, which are either habitable or inhabitable. Kortoso (talk) 00:59, 27 November 2013 (UTC)

Life on Venus?[edit]

"The planets Venus and Mars, along with several natural satellites orbiting Jupiter and Saturn, and even comets, are suspected to possess niche environments in which life might exist." I have no quarrel with most of this statement, except for having included planet Venus in this category. Venus was a candidate for extraterrestrial life a long time ago. Since the Venera missions new data was collected. Today we know much more about the climate and surface of Venus to discard many of the more optimistic theories about life in Venus. We know, for example, that it is not possible for life as we know it, to live in the surface of Venus, it is an Inferno with 92 atmospheres of pressure and 900 degrees Fahrenheit, cooking all there is and it is extremely dry. Actually there are only a few defenders of the theory that life may exists in the lower strata of Venus atmosphere, namely, Carl Sagan, David Grinspoon and Dirk Schulze-Makuch, but it is worth mentioning that Sagan died in 1994 and he was relying on data that was publicize in the 70's. So his hypothesis will probably have change in light of new data today. The other two, namely Grinspoon and Schulze-Makuch, both publicized their hypothesis more than a decade ago with the exception of Schulze, who did it in 2004, but to my knowledge there has been no follow up of this idea, particularly when new data has shown that Venus is so dry that if you were to squeeze it, all the water in the planet (including its atmosphere) would amount to no more than a 3cm-high ocean. Moreover, we know that Venus looses a great part of its atmosphere due to solar winds, which makes it even drier. So, even leaving aside the possibility that there may be some form of life still resilient enough to live in this super-dry environment, it would not be water based. Given the above, it is safe to assume that probabilities rule out the scenario of life thriving or even been able to exists in Venus Atmosphere. Therefore, to say that "Venus is suspected to possess a niche environment in which life might exist" is actually false. There is no reasonable chance for suspecting that life may exists in Venus given what we know of Venus' atmosphere and surface today. — Preceding unsigned comment added by Sandokant (talkcontribs) 14:41, 19 November 2012 (UTC)

Please read WP:No original research. Editors do not argue with sources, they simply present reliable sources and what they say. If you properly cite sources saying that this hypothesis is not considered tenable by the scientific community, we can add that after the current line. Ian.thomson (talk) 14:49, 19 November 2012 (UTC)

One of my main sources is: "Assessing the Plausibility of Life on Other Worlds" by Louis Neal Irwin and Dirk Schulze-Makuch. Astrobiology. June 2001, 1(2): 143-160. doi:10.1089/153110701753198918.

But I also want to stress, that by the very nature of the question it is extremely difficult to address the untenability of this hypothesis in the scientific community, because there are simply no polls that show what are the thoughts on the matter about this in the scientific community (as there are none about the possibility of life on the Moon). In any case, I do not think that it would be necessary for saying, for example, that Carl Sagan was one of the few scientists who thought that there may be forms of life thriving on Jupiter's atmosphere, although actually almost nobody in the scientific community would be giving it much thought nowadays. The question is not if I am doing original research, which I am not, but if the statement in the article, as it has been put, really reflects current scientific views on the matter, that is: If "Venus is suspected to possess a niche environment in which life might exist" and if the scientific community really believes it so. That is a statement, which anyone interested in the search of extraterrestrial life will certainly answer with a definite NO. Which, by the way, does not rule out that possibility, but that was not the question. Listen, the only thing I am arguing is the framing of the statement, which does not reflect the main scientific perspectives on the matter, not that there is no possibility of finding life on Venus, which is an entirely different matter altogether. (After all, the statement "there could be life on the Moon" has not been refuted by science, but it does not mean that believing that 'there could be life on the Moon' reflects the main scientific perspectives on the matter). Just change the framing of the statement by saying that it is a possibility, but does not reflect the main trends in current scientific research of extraterrestrial life in the Solar System and many of us would be more than happy with the result. I can do it myself, without omitting the opinion of scientists who, like Sagan, defended or still defend that view (which still does not reflect the main scientific opinion on the matter) Thank You.Sandokant (talk) 03:06, 20 November 2012 (UTC)

Life before Earth?[edit]

relevance:extraterrestrial life, panspermia, origin of life, evolution, Moore's Law http://arxiv.org/ftp/arxiv/papers/1304/1304.3381.pdf 217.89.117.154 (talk) 08:58, 18 April 2013 (UTC)

Curiosity illustration - Mission is not an attempt to find life[edit]

Why is Curiosity used as an illustration when it is not equipped to or designed to find life ??? Its mission is to find evidence of past habitability. --EvenGreenerFish (talk) 05:33, 13 May 2013 (UTC)

FWIW - seems the Curiosity (rover) may not have instruments capable of detecting life forms directly - unless the life forms could be imaged of course - but the rover seems to have sufficient ability to determine some conditions of habitability that may allow (certain?) life forms to survive - see => Timeline of Mars Science Laboratory#Evidence for ancient habitability (and Lichen#Overview and lichen survives Mars conditions) - this limited rover ability is, at least, on the way toward finding life on Mars I would think - in any case - Enjoy! :) Drbogdan (talk) 14:09, 13 May 2013 (UTC)

Citations not needed?[edit]

In "Indirect search" para 1, two statements are flagged as needing citation. The first (that putative extraterrestrials might not be broadcasting comprehensibly to Earth, or at all) is self-evident if one accepts the mathematical laws of probability, and the second (that electromagnetic signals received from distant astronomical bodies would have been created in the far past) is a consequence of the finite speed of light, as per Special Relativity. Both are part of fundamental scientific knowledge. Does the editor doubt them? 121.99.93.160 (talk) 01:01, 29 June 2013 (UTC)

Whacky underground alien speculation[edit]

Removed this speculative claim:

Subterranean tunnels in the United States have also been investigated for extraterrestrial life.[73] Due to advances in Gravimetry, colorful images are available to assist scientists in uncovering potential underground cities.[74][75]

Citations were provided, but they did not support the claims. Such claims are pseudoscientific, based on conspiracy theories and though they are technically a form of SETI have little basis of fact. Even if was plausible that an advanced alien species could have hidden bases on Earth, to specifically claim that there could be "cities" underground in the United States is a pretty enormous stretch.--EvenGreenerFish (talk) 06:01, 8 July 2013 (UTC)

Malware Link Removal[edit]

--Gary Dee 18:21, 21 July 2013 (UTC)

Not neutral[edit]

"The failure so far of the SETI program to detect an intelligent radio signal after decades of effort, has at least partially dimmed the prevailing optimism of the beginning of the space age. Notwithstanding, the belief in extraterrestrial beings continues to be voiced in pseudoscience, conspiracy theories, and in popular folklore, notably "Area 51" and legends. It has become a pop culture trope given less-than-serious treatment in popular entertainment with e.g. the ALF TV series (1986–1990), The X-Files (1993–2002), etc."

That hardly sounds neutral. No source, obviously an opinion representing a more cynical point of view, while implying that pseudoscientists, conspiracy nuts and sci-fi fans are the only groups of people believing in extraterrestrials. Meanwhile, there are legitimate astronomers, physicists, and mathematicians, who believe that extraterrestrials are not only likely, but statistically sure to exist. Not to mention the amounts of proof pointing to it. Even people like Hawking, Kaku, and countless others have supported the "pro-ET" stance on numerous occasions, and I wouldn't call them "pseudoscientists" (while some may think that being a popularizer of science somehow makes a person a bad scientist, it's not really the case). And while I doubt they're among us "Men in Black style", the support for their existence is hardly coming only from pseudoscience, conspiracies, and sci-fi. That whole paragraph is unwarranted, not needed, untrue, and doesn't really add anything of value to the article. It should either be rephrased, removed, or moved to a section about skeptical views on the matter.

http://www.telegraph.co.uk/science/space/7631252/Stephen-Hawking-alien-life-is-out-there-scientist-warns.html http://www.huffingtonpost.com/2013/03/19/aliens-the-definitive-guide_n_2909012.html

I agree it could benefit from a source. But I don't think its central point - that the "profile", if you like, of ETs in popular culture is significantly higher than in science - is a terrible one to make, and the article elsewhere does give plenty of space to serious scientific support for the concept. Barnabypage (talk) 09:57, 4 October 2013 (UTC)
No experiment is a failure if it returns data. That said, SETI is still in its infancy, and has yet to scratch the cosmic surface, so to speak. Kortoso (talk) 01:02, 27 November 2013 (UTC)

Simple minded error of knowledgeability, elementary Arithmetic, and as ever ... .[edit]

9.7 +- 2.5 is not "billions of years before the earth formed". The Earth is 4.5 billions years old. This universe is 13.5. You cannot take the minus end of the range like that, it needs to be qualified by "possibly" instead of stated as if the 7.2 value of the range was an established fact. That's why it's an interval and not a simple number. The facts as stated just as positively support the first life arising elsewhere after it did on the Earth. in as much as life on Earth is itself billions of years old. Animal life here is only about a half a billion and assuming the same time is generally required it's quite possible this is the first world on which animal life developed, just numerically unlikely, assuming the Copernican principle. Given the stated data, current best understanding of things, the earliest time that life could have reached the animal stage is about 2.5 billion years ago by which time it was well established on the Earth so this is more typical crowd sourced misinformation. This shows why they're called the ignorant masses. Lycurgus (talk) 18:08, 18 December 2013 (UTC)

FWIW - Seems like a lot of uncited opinion (and/or presumptions?) - (WP:OR?) (WP:NOTAFORUM may apply?) - re sourced material in the main article - unclear how your comments help improve the main article - worthy text material supported by WP:RS, WP:CITE and/or related - to improve the main article - welcome of course - in any case - Enjoy! :) Drbogdan (talk) 13:57, 18 December 2013 (UTC)
Mein Herr Doktor, the use of the honorific in your username is telling (of an apparent intent to pettifog). 198.255.198.157 (talk) 20:52, 18 December 2013 (UTC)
Thank you for your comments - nonetheless - any sourced text & related to consider for the main article welcome of course - in any case - Enjoy! :) Drbogdan (talk) 22:34, 18 December 2013 (UTC)

NASA-TV (07/14/2014-2pm/et/usa) - Search for Life Beyond Earth.[edit]

NASA-TV - Monday, July 14, 2014 (2:00-3:30pm/et/usa) - panel of leading experts to discuss plans leading to the "discovery of potentially habitable worlds among the stars" => < ref name="NASA-20140710">Brown, Dwayne (July 10, 2014). "MEDIA ADVISORY M14-117 - Leading Space Experts to Discuss the Search for Life Beyond Earth". NASA. Retrieved July 10, 2014. </ref> - Enjoy! :) Drbogdan (talk) 17:17, 11 July 2014 (UTC)

FOLLOWUP - NASA VIDEO REPLAY - Space Experts Discuss the "Search for Life in the Universe" (86:49) at => http://www.youtube.com/watch?v=GNjuz6MO0eU - Enjoy! :) Drbogdan (talk) 12:47, 15 July 2014 (UTC)