When will we know we have found extraterrestrial life?

This is the "South Pillar" region of the star-forming region called the Carina Nebula. Like cracking open a watermelon and finding its seeds, the infrared telescope "busted open" this murky cloud to reveal star embryos tucked inside finger-like pillars of thick dust. Credit: NASA

(Phys.org)—As we become more advanced in astronomy, continuously searching and finding lots of potentially habitable extrasolar planets that could harbor alien life, it seems that it's not a matter of if but when we will find extraterrestrial organisms. However, the real tough problem here is: How we could determine if the alien life has really been found? "The question is not so much 'when will we find extraterrestrial life?' But 'when will we know we have found extraterrestrial life?'" Terence Kee, the President of the Astrobiology Society of Britain told Phys.org. "My feeling is that we may indeed find signs of life in a few decades, but whether we will be unambiguously able to identify it as 'extraterrestrial life' - as opposed to terrestrial contamination or abiotic far-from-equilibrium processes - in such a short time-frame, I'm not so sure."

Kee noted that we are able in any realistic sense to detect only forms that have a terrestrial-based biochemistry, so we would probably bet on bodies that have liquid water and some form of geological free energy source. He puts his hopes on space probes looking at out-of-equilibrium gas distributions in exo-planetary atmospheres. However, any potential findings revealed by these probes would be only an indication, without the capability to definitively determine the existence of alien lifeforms.

We could also turn to meteorites in the ongoing search for E.T. and hope that these rocks came from a parent body that may have harbored life. If we're lucky, relics of life are contained within that sample and have not been destroyed. Kee surprisingly admits that luck is really the key condition here.

"As most of these relics are likely to have been fossilized in some way, we would need to cash in on some more luck so that we can demonstrate sufficient differences between such relics and potential abiotic mechanisms of formation on earth—chemical compositional differences, isotopic ratio's mineral morphologies or, most valuable perhaps, presence of specific molecules which could only be produced by biogenic processes, etcetera," he said.

The biggest challenge is to clearly identify if the existed on the studied meteorites a long time prior to re-entry into the Earth's atmosphere. Before that is established, any new finding would be just a potential signature of extraterrestrial life. For example, in 2011, Richard B. Hoover, an astrobiologist of NASA's Marshall Space Flight Center, claimed he had found the remains of living organisms from a parent celestial body in a rare class of meteorites, called CI1 carbonaceous chondrites.

"The complex filaments found embedded in the CI1 carbonaceous meteorites represent the remains of indigenous microfossils of cyanobacteria," Hoover claimed.

His team used Environmental (ESEM) and Field Emission Scanning Electron Microscopy (FESEM) to analyze the samples, studying internal surfaces. For comparison, Hoover compared the samples to those of terrestrial minerals and biological materials.

Hoover's claims sparked controversy and NASA distanced from his conclusions, pointing out his lack of expert peer reviews. The findings were soon debunked after publication.

More recently, two scientists suggested that the comet 67P/Churyumov-Gerasimenko, which is studied by the European Space Agency's Rosetta spacecraft, hosts microbial alien life. The University of Buckingham's Chandra Wickramasinghe and his colleague, Max Wallis of the University of Cardiff, insist that the characteristic features on the comet, including a black, carbon-containing crust and underlying ice; large, smooth 'seas'; flat-bottomed craters and a surface peppered with mega-boulders, might only be explained by the presence of life.

But the last week's claims also sparked skepticism among other scientists specializing in the search for , debunking the newly presented hypothesis. The researchers rejecting the new findings emphasize that complex organics are generated in many places in the solar system through photochemistry and this is evidence for anything other than abiotic chemistry.

So far, we haven't found any convincing proof of embedded in meteorites. However, Kee, undeterred by the long-lasting search and continuous skepticism, is looking to the future with hope.

"In order to receive Willy Wonka's Golden Ticket of Astrobiology, we would need to be ready to search as many meteorites as we can get hold of, which we already do. Overall, I reckon we would need to be lucky. But hey, many people have won the lottery. The trick is to keep buying the tickets," Kee concluded.

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Jul 10, 2015
I am pleased that all these recent wild theories are proving to be baseless. Particularly in regard to another article on this site that spoke about how bias and expectation of a result in science (which has prevailed upon the scientific process for some time) leads to rather inaccurate results.

Playing the lottery is also greatly misleading to the odds that face circumstantial spontaneous emergence of life from non-living matter. Odds that make winning the lottery look as if it's a certainty. At least some scientists out there realize that these odds make the discovery of life or even the emergence of it so unlikely that if it is how we arrived there is horrifically diminishing odds that it would occur a second time. So much so that if an article claims to have found life I feel safe in assuming contamination created by our own probe.

It's also why every time an article about finding life comes out I don't hold my breathe.

Jul 10, 2015
First, I really wish reporters didn't go off on crackpots. Hppver and Wickramasinghe are two nuts of the same case, Hoover has 'found' life 3 times [ https://en.wikipe...._Hoover ] and only creationist and conspiracy theorist Wickramasing knows how many times he has 'found' it.

Second, detecting life is no different from other observations. There can be conflation, but also not. Specifically here we already know are atmospheric combinations like O2 in combination with H2O and CH4 which testably differ from abiotic conditions.

Finidn local life is possible and interesting, but also much more difficult. We know how to constrain Earth fossils so that there are no confounding geological processes. We don't know how to do that for meteorites.

Jul 10, 2015
Speaking of crackpots, observing life has nothing to do with how rare emergence would be. And of course Pasteur could reject creationist random "spontaneous (poof) emergence" already 2 centuries ago. Not that creationists care...

We already know from the short time it too life to emerge on Earth that it is not a difficult evolutionary process. In fact the now reigning fuel cell theory is already well tested and is high likelihood.

Jul 10, 2015
Speaking of crackpots, observing life has nothing to do with how rare emergence would...

Until the object is actually living natural selection just does not occur. What if find in the end most evolutionary theorists break down to is one statement, "however life started, we are here so proof."

Proof that life merely is, not how it arose. Also so quick to simply disregard math which is a fundamental process of science, yes including probability!

If it was an open and shut case fuel cell theory would be prevalent but there is no accord among evolutionary theorists so no there is no hard definition on how life started. No evolutionist has ever given me a scientifically satisfying answer. Simply put because the credible scientific community acknowledges it does not know how life emerged. So don't talk about theories as if they are facts.

Jul 10, 2015
Speaking of crackpots, observing life has nothing to do with how rare emergence would be. And of course Pasteur could reject creationist random "spontaneous (poof) emergence" already 2 centuries ago.

Oh? Elaborate.

Jul 10, 2015
Syndicate, thank you for your well thought-out comments. Scientists like Torbjorn have a very narrow worldview, and take theory almost as fact. Really sad. It is called a man-centric worldview.


That's rich coming from a young earth creationist that thinks the bible is a science text.

Jul 10, 2015
I am pleased... I feel safe in assuming...I don't hold my breathe.

We don't really give a shit what you think or feel, so STFU.

Jul 11, 2015
youtube dot com/watch?v=z16B3IP1Bbg

Millions have opened the Billy Meier site, theyfly dot com and read The Pleiadian Mission by US psychologist Randolph Winters, based on the Meier's 70+ years ongoing et contacts in Switzerland. Many here share common ancestry with this et race, descended from an ancient race from the Lyra Constellation, sun Vega. This group of et now claim to be 3,500 years ahead of us in tech, medicine and knowledge The Creational Laws. They have given us 1000s of pages of data!

Jul 11, 2015
Does it matter? Climate change has been known about since 1981, at least, but if you pay enough people to say the right things you create your own reality. It's still debated. You can discover very reliable evidence for extraterrestrial life tomorrow and I'll wager my last thin dime that it's been debated in 500 years.

Science will never trump the herd mentality. We breed more for that herd every day and they are not original thinkers. Be the farmer or be the livestock. You either dominate people or you are dominated. Knowledge is *only* useful to the extent that it is power. Knowledge for its own sake is worthless.

Inv #8030401

Jul 11, 2015
The Quantum erasure experiment shows that history is adjusted to support the observed reality.
We observe life here on Earth, therefore history is adjusted to support the observation.

Accept the results of the Quantum Erasure Experiment and all becomes clear. Nothing random, no other history possible because we observe life here now.

If we observe other life, then history will have been adjusted to support the observed life, no matter how improbable the mathematical odds are.

Jul 11, 2015
Millions have opened the Billy Meier site

Millions are gullible idiots that need to be culled.

Jul 11, 2015
A true skeptical scientist kneels before the empirical evidence. No matter how outrageous.
If someone observes a UFO then history and all of physics has to be adjusted to support that observation.
Regardless of anyone's sensibilities.
Once the observation is made.
The unwanted precocious child of science, Quantum Physics, has driven a wooden stake through Materialism.
It is going to take some time to die.

Jul 11, 2015
Hopefully, you'll be different. How's tomorrow?

Jul 11, 2015
Millions have opened the Billy Meier site

Millions are gullible idiots that need to be culled.

That includes the investigators at JPL in the utube, right?

If you know it's all bullcrap, that's fine. We all have our own truth.

Jul 11, 2015
@Egleton Note your inclusion of 'UFO'. The part about 'physics ...adjusted...' is not strictly true.
Example; many (good) UFO reports the erratic movement but no sound and speeds up 9000 mph have been recorded again, no sound.
Speeds less than mach 1 don't have serious air flow problems because the sound 'alerts' the air in front etc. >mach 1 shock waves build up because the air doesn't receive 'a signal' that an object is coming hence a sonic boom. But suppose some a way is found to 'alert' the air in front, thereby not creating a sonic boom? Now I wonder what travels faster than sound that could be used to send a 'signal'?
Okay, the above isn't rigorously accurate but you can see where I'm going on this. One doesn't have to think about 'anti grav' or 'neg grav' machines so although there may be some different method of actual propulsion it may be that our physics need not be adjusted.

Jul 11, 2015
What an incredibly scientific post ren...why does an all merciful all loving god of peace and harmony need an army of angels? Why does an omnipotent god capable of magic and miracless even need them? Couldn't he just cast those who oppose him into hell?
Your god sure has funny ways of doing things. Why has god been so quiet in the affairs of men lately? He talked and interacted with people in bible times regularly. What made him suddenly stop following after us influencing us as he'd been then?

Jul 11, 2015
@jsdarkdestruction Ha! and what happened to end of days etc at the point of 2000.

Jul 11, 2015
He talked and interacted with people in bible times regularly. What made him suddenly stop following after us influencing us as he'd been then?

.. referred to as the Gods were Lyrian ets. Why would somebody in those days consider a human arrivng in a beamship otherwise.

Et example. What locals could have known our sollar system rotates around the Pleiades once every 25,827.5 years. How could those locals build the Great Pyramid, in 71,344BC, with the base diagonal of 12,913.75 Pyramid", 1/2 the Rotation time around Pleiades?

One need to climb out of the matrix/box and realise what's happened in our past. The Smithsomian model of chimp 4M years ago, to Lucy in Ethipia, who goes on a 20K Km stroll and becomes Indian, Chinese, Eskimo etc is all smoke and mirrors to put you off balance.

Isn't there a gentleman who arrives regularluy on a S Pacific island in his Cessna 182 and is worshipped as a god?

Jul 11, 2015
Millions have opened the Billy Meier site

Millions are gullible idiots that need to be culled.

....and just ask every single one of those "millions" if they believe in Dark Matter & the positive response rate will be in the 99% range, which oddly enough is just a about the quantity of mass DM Enthusiasts claim is missing throughout the Universe.

There is a rumor going about that "Beyond GR" will soon appear as a peer reviewed paper with never before seen Field Equations relegating Einstein's thesis of General Relativity to the ashbins of science history. It supposedly contains a complete revision even of the non-linear PDE's in GR & provides hard numbers to things even Einstein was not able to do. In short, "Beyond GR" will become Billy Meier's holy book brought to you by his prophet(ess) JeanTate.

Jul 11, 2015
It seems to me that we will need to be able to recognize intelligence on this planet first, no matter how alien and bizarre, before we start lifting the figleaf on other planets.

For instance, how many would be willing to entertain Kenneth McKenna's transcript of The Mushroom speaks?
If not, why not?
It speaks to a failing on your part if your mind has ossified.

Jul 11, 2015
Dark Destruction:

Actually, there are voids of as much as 400 years between some of the prophets, and another 200 something years between the last recorded OT prophet and Jesus.

However, to answer your question, God talks to people all the time in modern times.


He doesn't "need" them. They are another created race, just like humans but in a different manner of creation. He chooses to allow us to exist and have free will, often times harming one another, etc. So it is no small wonder that he may also choose to allow some angels to be evil (demons/fallen angels whatever you want to call them) and allows others to fight them.

Just because God is omnipotent does not mean he automatically chooses to micro-manage every action and thought of every being.

We are created in the image and likeness of God. We have to power to do good and evil, and the power to procreate, and we even have the power to create other lifeforms in our own image and likeness: A.I.

Jul 11, 2015
Why do authors write books with "good guys" and "bad guys"? Why is the social normal for books and movies such that the "good guys" always win?

Like it or not, and whether or not you realize it, you are just emulating the behavior of the omnipotent God: You create "characters" in your own image and likeness, or not, perhaps some are good, perhaps some are evil, some are superior, some are inferior.

Why do you question God's authority to do the same things you and other human beings do every day?

Jul 11, 2015
I don't really care how long we've been here (I'd like to know, as I'm sure everyone would,) and I don't care how many races of angels or other intelligent alien beings there might be. We'll never meet them all in this life anyway. None of those things change the cosmological argument in the least.

Jul 12, 2015
Problem. ALL scientists would like to be the 'first' to discover. However if any ONE claims to find life and IS credited for it, then NO other scientist or group will ever be able to claim its discovery ever again except as 'number two. In this game, WINNING is not just the idea, it is like football. It is the ONLY thing. So if one claim is made, then ALL other scientists eager for funding and money will attack that claim with a fury borne of greed, selfishness, envy, and hatred of the success of others. For this reason and principally so, our research and discovery aims are flawed if altruism is not mandated by law so that no matter WHO claims life, the whole species of humans are equally given credit. For NO education is given in a vacuum, but all educated persons are dependent on society for their gifts however hard won.

Jul 12, 2015
@Returners, Ha you obviously had the 'free will' to ignore the commandments. People who talk about 'religious free will' are following an excuse to do as they please. 'Thou shall NOT kill' etc hardly allow for your interpretation of 'free will'.

Jul 13, 2015
@Returners, Ha you obviously had the 'free will' to ignore the commandments. People who talk about 'religious free will' are following an excuse to do as they please. 'Thou shall NOT kill' etc hardly allow for your interpretation of 'free will'.

The fact that the commandments can be broken, and are broken all the time by pretty much everyone, proves you have free will.

How can you be so clueless?

Jul 14, 2015
I would expect the range of morphologies of alien life to be similar to that of Earth life, especially if it is carbon-based AND under the assumption that it has the functionality of a Eukaryotic cell, whether having a mitochondria equivalent or whether it does the job of the mitochondria on its own. If the life form has solved this problem, either way, then its morphology will be predictable because the forms found on Earth are already nearly idealized in the case of most organisms we normally think about; the torpedo shape of sperm, whales, sharks, etc. The fins of fish analogs to the wings of birds. Therapods and quadrupeds, hey maybe they are tripodal or pentagonal (like starfish), but those forms are predictable, especially if it is carbon-based.

Thus I would expect most alien life to look just like Earth life. There will be mostly prokaryotes or something functionally similar, and once in a while you might find something similar to a eukaryote.

Jul 14, 2015
However, if the life is not carbon-based, the possibilities become strange.

Consider a slica or metallic based life form, like a solar-powered robot which is inclusively fit and able to replicate itself. It fits the defintion of life, especially if it is able to adapt to it's environment in addition to self reproduction.

Unsure how this life form might exist? Hey the same Creator who made us could easily have made us as solar-powered metallic robot-like beings, but the Creator didn't do that in our case.

We can easily imagine something like the Terminator or the Synths in the new series "Humans", and we can easily imagine that the Creator set in motion "life forms" which may emulate those characteristics.

Imagine an "animal-like" life form which is composed of silicon and metal-based cells which convert solar power to energy, chemistry, and motion....an "organic machine", but not carbon-based.

When I say not carbon-based I don't mean it has "no carbon".

Jul 14, 2015
Far fetched?

I don't think so.

Humans have created "robots" which are formed of collectives of smaller member robots (usually cubical constructions) which attach to one another and form structures none of them can make individually, such as an arm with 6 degrees of freedoom, or wheels, or legs to move around. It is the same principle as "cellular life", but scaled up so that humans can work with it in terms of the computers and machine components we understand.

Carbon-based Cellular life does all this at the microscopic level.

There is no reason a metallic-based life form couldn't do the same thing, provided it has a way to do chemistry with its environment and absorb energy with the environment either through solar power, or through consuming chemicals which produce exergonic reactions. It might eat/breathe sulfur or hydrochloric acid, like some microbes on Earth do, or it might simply survive by converting thermal energy to electro-bio-chemical energy, etc.

Jul 14, 2015
However, morphologies are mostly predictable:

Plant-like morphologies:
soft-wood trees: Tall and slender.
Hard-wood trees: shorter, but fatter and spreadingi branches more broadly.
"Leaves" obviously to collect sunlight and atmosphere.

Then you have othe rlife forms like mosses, molds and lichens.

If you want to predicta alien life, all you need to do is study present-day and past Earth life, AND assume that the life on Earth is a sub-set of all possible life; alllow a little room for abstraction and so forth.

If the alien life has not developed cell membranes and cell walls, then it may be a hap-hazard collection of free-floating organelles which work together ina collective. I would not expect such a system of life-components to be very reliable or successful, but there is no good reason it can't exist.

Jul 14, 2015
Far fetched?

Yeah, it is, but it is what you do to while away the hours between treatments.


You are the only couyon I know who can write more postums that everybody skips overs than Zephir-Skippy can write to him self. You are up to 30 or 29 today Cher, don't you want to take a nap?

Jul 14, 2015

Try to let your mind expand, your consciousness expand to develop new ideas, instead of only parroting what other people do.

To develop ideas is not pride. It is an acceptance of what you are, without being enslaved by other people's narrow-minded biases.

If you want to know what alien life might look like, just become an oceanographer, and then add some imagination.

Jul 14, 2015

Try to let your mind expand, your consciousness expand to develop new ideas, instead of only parroting what other people do.

I am the independent operator, I do what I do.

To develop ideas is not pride. It is an acceptance of what you are, without being enslaved by other people's narrow-minded biases.

But it makes it hard to find an honest job. All humble idea developing I mean. I got the really good job. You don't even have a really bad job.

If you want to know what alien life might look like, just become an oceanographer, and then add some imagination.

Well if it is in the ocean, it's not alien then is it Cher?

Jul 14, 2015
P.S for you Returnering-Skippy. Who is this Gilligan-Skippy you keep bringing up?

Jul 14, 2015
Hooyeei Skippy good night.

Jul 27, 2015
We shall know too late.

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