Slashdot Mirror
Proposed Indicator of Life On Alien Worlds May Be Bogus
sciencehabit (1205606) writes with bad news for anyone hoping to use the spectral signatures of exoplanets to determine if their atmospheres have life-enabling compositions. "Call it the cosmic version of fool's gold. What was once considered a sure-fire sign of life on distant planets may not be so sure-fire after all, a new study suggests. The signal—a strong chemical imbalance in the planet's atmosphere that could only be generated by thriving ecosystems—could instead be the combined light from a lifeless exoplanet and its equally barren moon."
Uhmmm. What?
If we found an exoplanet with signatures that suggested the atmosphere might support life, billions and billions of astronomers would be analyzing light/gravity/etc from every possible angle.
So it isn't like it wouldn't get unprecedented peer review (remember how initial lander photos of Mars showed a blue sky, as an example).
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
That's no moon.
Assuming we actually FIND something/someone to talk to out there..
We will NEVER be able to get there, or ever hope to even send something there (where ever there might be) and they are not coming here. We'd be better off trying to catch their attention by doing the cosmic equivalent of yelling (i.e. sending strong radio pulses) at them. But it's going to be like trying to get the attention of a rock fan in the mosh pit from the back row in the stadium using your cupped hands. Not to mention that it's going to take about 9 years to get a response if we found a habitable planet around Alpha Centauri, which so far has not been forthcoming. (Nearest possible place is 20+ Light years round trip).
It may be fun to look, but it's pretty much useless.. We are here to stay at this point. At least until we can figure out how to go faster than the speed of light, safely. And if we can do that, we can get out of black holes too...
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
I don't think we could know up front what good life indicators are. Basically we see if anything looks odd or promising, form theories, and investigate more to strengthen or falsify such theories with new data and tests.
Mars' goofy and teasing soil and rock chemistry* should have taught us that searching for life is likely a long and winding road (barring a direct landing party with a big lab).
* This includes seasonal changes that looked like vegetation seasons to early telescopes (turned out to be seasonal dust patterns), Viking's "positive" results, the "magnetic worm" meteorite, methane detection, etc. Bill Clinton even jumped the gun with a "life!" press release.
Table-ized A.I.
And if we find 3 planets with the signature in the same system? Or we find 100 systems with the signature? How likely is the planet/moon signature? It seems that, it may be proof enough if we find it in the right way.
As an earthling (a clumsy term for our planetary residents at best), any information that suggests we are farther along the great filter than probability would dare suggest is welcome news.
If there is no other life in our perceivable light cone, we just might be the universe's best shot at a colonizing species!
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
A strong indicator of life would be continents that spell out "Go Home Yankee!" (Or "Go Home Yankees" if occupied by Red Sox fans.)
Table-ized A.I.
If there is no other life in our perceivable light cone, we just might be the universe's best shot at a colonizing species!
In that case, the universe is very severely fucked.
Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
These planets are so far away from Earth, the only way humans would get to them would be through Oculus Rift. Some people believe humans will figure out faster than light travel, but this is a fantasy. Human beings can't even figure out how they can stop burning their planet for energy.
I find that rather disappointing rather than welcome news. I would much rather learn we are at best average and have the potential to massively accelerate ourselves through encountering others further along the curve.
It sure has a chemical imbalance, but then again, I had Taco Bell for lunch...
"Unheard of means only it's undreamed of yet,
Impossible means not yet done." ~~ Julia Ecklar
So let's say you're an advanced interstellar civilization looking about for other worlds with life for trade and/or colonization. You have system spanning optics capable of resolving individual planetary systems and resolving the atmospheric spectra thereof. And you find a small yellow star with 8 or 9 planets, including a couple of respectable gas giants and three rocky planets in the habitable zone. Two of those rocky planets clearly have stale atmospheres that have long ago achieved chemical steady state. But the third has an interesting mix of O2, CO2 and CH4, along with multiple other hydrocarbons, all apparently far from a stable state.
But alas, that planet has a HUGE moon... a well-known explanation for the spectra, and the cause of many, many failed planetary exploration missions.
The investment bureacrats HATE uncertainty. If you take a risk and it fails, it will cost your entire clan their wealth and status. You instead decide to commit your finite resources to explore planets with more exploitable natural resources than humongous gas giants and small rocky planets deep within the stellar gravity well.
I can see the fnords!
Wouldn't that be ironic, with all our frailties and foibles, we're the Universe's best plan for creation of its own observer.
Kind of intimidating, really.
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
We just give them a high intensity focused radio broadcast of "Big Bang Theory" or "The Office" and wait for them to become hooked.
Like Futurama aliens getting hooked on "Single Female Lawyer".
The rest handles itself. Two way communication is highly overrated anyway!
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
Comment removed based on user account deletion
Well --- we kinda know what the bad for life indicators ARE!
1) Tidally locked gas giant with orbit of star = 3 days = sucks.
2) Shitty ice planet 15 AU from star = sucks.
3) Super Earth orbiting Pulsar and Blackhole Pulsar = Sucks
4) Hot Planet 318 the size of Jupiter = Sucks
Etc.
I think we know the definition of sucks = most of the ones we've found so far since our current methods tend to find the gigantic ones, so we certainly know what NOT to look for!!!
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
Can't remember who said it, but someone once said, on looking up at the stars "A sorry spectacle: if they be inhabited, what a scope for misery and folly. If they be uninhabited, what a waste of space".
Whoever it was, was a pessimist.
"The greatest lesson in life is to know that even fools are right sometimes" - Winston Churchill
If there is no other life in our perceivable light cone, we just might be the universe's best shot at a colonizing species!
In that case, the universe is very severely fucked.
Only if you think nature a fool: Adapt or become extinct. The universe shapes the form of its inhabitants, not the other way around. Perhaps you fail to consider that organics are merely a tool to produce more flexible and durable inorganic life forms capable of surviving the harshness of space, similar to the way chemistry and entropic reduction is merely a tool to cause the self assembly of organic forms, similar to the way the laws of physics are merely a tool to crystallize matter out of energy.
You see, we cyberneticians can transport a simulated intelligence into reality by simply replacing their simulated sensors and frames with real cameras and chassis in the physical world. However, if the intelligence is easily serializable as a string of bits then one can simply copy the intelligence from the simulation directly into a waiting body in the greater reality.
Naturally, one wouldn't see but a single source of intelligent life per universe, as this would not be conducive to differentiation in the output optimized machine intelligence that emerges therein. Multiple instances of life tend to coalesce into a single species or single organism over time (as evidenced by your own multicellular body). It is more humane to use artificial isolated simulations to produce new ideas and perspectives than to enforce permanent loneliness through mandatory ignorance of a divided universal mind.
This idea would only work if either the planet's moon was right in front of it from out point of view, just going behind it or just coming out from behind. That means that even if the orbit was oriented just right, we'd only get the filtering effect intermittently. Of course, it's possible that the planet's orbit is such that we only see it at just the right time, but that's pilling one unlikely coincidence on top of another.
Good, inexpensive web hosting
We tell the Corporations any planet with interesting chemistry contains Unobtanium.
Embarrassing if alien life was checking Slashdot. The editors would convince them there is no intelligent life on Earth.
"of of" indeed.
Never answer an anonymous letter. - Yogi Berra
Well where I'd have to disagree, is that we know what sucks... We know what sucks for life, that evolved in the conditions of earth. We can't even imagine what life outside of our conditions are, assuming it is possible. Sometimes I think assuming that the nearest life, is most certainly going to be needing a water ritch atmosphere with oxygen hydrogen and CO2 in the atmosphere, is similar to coming to the conclusion that if we find inteligent life similar to us, we should expect them to speak chinese, because that is what the majority of inteligent life capable of complex communication in which we are familair with speaks
This news says absolutely nothing about the chance of life elsewhere in the universe... it only says something about our chance of being able to detect it as such.
File under 'M' for 'Manic ranting'
Seems like a bit of a stretch... if we discover a world, and if that world has an atmosphere and if that atmosphere has one of the chemical compounds associated with life and if that world has a moon and if that moon has an atmosphere and if that atmosphere happens to have an equivalent/opposite chemical compound associated with life and if those two bodies happen to line up so we can sample both atmospheres at the same time, THEN we might falsely conclude there is evidence for life.
Seems like our current situation might be much more common...a world with life and a moon devoid of any atmosphere....
Well, you probably agree that life is likely to be made of molecules, right?
If you agree that life is made of molecules, then you need to have an environment that can form complex molecules and that it needs to do it during a period of a several billion years.
1) A boiling planet isn't going to form complex molecules the same way plasma doesn't form complex molecules (plasma = too hot to keep electrons).
2) A 3-degrees above absolute zero planet isn't going to form complex molecules in a trillion years because super cold makes everything into a solid that would react very, very slowly at best.
3) The star system better not emit intense bursts of energy 15-times per second, like a pulsar that emit high intensity radiation like xrays that knock apart chemical bonds and rip molecules apart.
So sure, maybe there is life around that is unusual compared to ours, but if it is made of molecules, we sure know what doesn't support stable evolution of chemical complexity in a reasonable period of time (several trillions years for a cold planet to facilitate reactions means everything in the entire universe except some small red dwarfs will have long died out).
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
But you are ruling out Hortas, dude
Table-ized A.I.
OK, this research based upon the observation of planets and the number we have visited, wait, what, it is just based upon hypothesis which in turn is based upon hypothesis because we have as yet to reach planets in the habitable zone of other suns so as to confirm or deny hypothesis and convert them into factually scientific theory.
As far as I am concerned the logically reality is every planet that is in a similar envelope of sun age, sun type and distance from the sun is not only inhabitable but inhabited (baring probabilities of total extinction impacts and the time required to recover). As soon as they start visiting other planets either directly or remotely, based upon what they actually discover rather than guess about, I might or might not have to revise my hypothesis.
Chaos - everything, everywhere, everywhen
"These are not the spectral signatures you are looking for."
Have gnu, will travel.
You didn't exclude Jupiter or Saturn in your list of issues. So should we expect to find some giant gas-bags on Jupiter eventually?
Learn to love Alaska
I truly hope not.
We probably should clean up our own house and get our act together before even considering exporting our poison to other unsuspecting corners of the universe.
potential to massively accelerate ourselves through encountering others further along the curve.
To those further along the curve.... our species might seem like pests; mosquitos to be controlled to limit our ability to reproduce and spread disease throughout the cosmos.
Like mosquitos, we can be stopped by making sure not to leave any planets around with standing water, air, or carbon based compounds in their atmosphere or near their surface.
The thing that bugs me about all these claims of planets and star wobble and theories on how to predict life and all are all based on the latest iteration of conjecture.
The light being examined is really, REALLY ancient. There's no (as far as I can tell) any leeway given to what may be between the star and us - like dust, or any other thing like dark matter (which is a theory) between us and the exoplanet - Honestly?
To me all this planet discovery is about as verifiable as the canals of mars were when I was a kid.
A star "wobbles" after 15 million years of the light traveling to where we can observe it - and It's as definable as the canals of mars were 40 years ago?
Really? I can't say that the people declaring plants and life are wrong - but then again, science about the near planets is woefully lacking.
How can we definitively say that life exists light years away when we're fucking clueless about what is going on under the surface of Europa?
_ _ _ Go for the eyes Boo! GO FOR THE EYES!
Yeah, but the absence of life out there sort of implies to me that it might be harder for us to actually colonize alien worlds. Creating a viable ecosystem is a lot more than just seeding plants/animals/genetic matter in a previously lifeless environment. You'll have to start out with the most primitive unicellular life our planet ever produced (you know, the first living cells to come out of the primordial soup?) - then, when they've altered the lifeless planet enough to make it tolerable, you'll need to introduce life that can survive in that nearly lifeless environment . . . in short, you'll have to try to compress several billion years of evolutionary changes to the ecosystem into something resembling a human lifetime or less.
If there's life already present, a lot of the preliminary work may be done for us - as long as we don't run into anything that's 1) smarter then we are, and 2) thinks we're just delicious.
Delicious, especially when broiled and smothered in BBQ sauce.
so you think that a species so incredibly advanced as to be able to cross the vast regions of space giving them almost unlimited resources and advancements in technology with the ability to swat us like flies would really give a shit about squashing us? at worst I would expect complete indifference from them as to our existence, should they exist and they considered us a threat we would be dead already.
There is no way Earth is the only planet with life in the universe. Even if you reduce the probability of life on a given solar system to almost nothing, like winning the lottery, the sheer size of the universe with its almost endless amount of stars and galaxies makes the odds for life somewhere in space and time extremely favorable.
Now the odds of that space and time being close enough to our little bubble of existence for us to take notice, that is a different matter.
Here is a non-paywalled version (any time you see a paywalled astronomy article, you can always find a free version on arxiv.org).
I've only skimmed the article, but I did not see any mention of doppler shifts in it. I would imagine that a planet+moon system would exhibit a time-dependent doppler shift of the moon atmosphere relative to the planet atmosphere, which would make it possible to disentangle the two. However, for an Earth-Moon situation, with a relative velocity of 1 km/s, the doppler shift will only be lambda/(delta lambda) of about 3e5, which is much smaller than the spectral resolution they are assuming (1600), so perhaps it doesn't work.
Indeed, they need to realize just how much greenhouse gas interstellar spaceships create.
A lot
Pigs in Space?
Colonizing an alien world would be difficult indeed, and colonizing a dead alien world orders of magnitude more difficult than that.
It's not that we'd expect no other life in the universe. We're exploring the premise that we've evolved further than most other examples the universe has to offer, leaving us with the obligation to fulfill the role of settler of the whole shebang.
If advanced life, with the big brain and the good hands is ubiquitous, it is likely we have some future step in the cull of the filter that we are infinitesimally likely to overcome.
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
Hortas are the children of the Flying Spaghetti Monster. They just have smaller meatballs.
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
Why is that? Within living memory, we left the atmosphere for the first time. It's a little premature to look at budget negotiations and NASA's budget and conclude that we will NEVER EVER EVER colonize space. You and I would consider waiting another thousand years for humans to colonize another planet depressingly long, but considering the universe is something like 16 billion years old: it's not in any hurry.
should they exist and they considered us a threat we would be dead already.
Pest does not mean threat.
They may have already obliterated us, or the last carbon-based species, by dropping their antibio weapon on mars millions of years ago, but a pocket if their adversary survived the first attempt at extermination and hasn't been detected so far.
Also.... we might be on the endangered species list now.
your thinking is too constrained by the struggles and tribulations that result from the limited resources, space and political bickering that we have on a crowded planet. You could give every person on the planet their own galaxy of billions of stars and their would still be no reason to ever even come across another species or for them to be concerned about us. The idea that other species are somehow going to act in the same way we do is silly. It is like suggesting Obama would send the US army to exterminate a newly discovered ant species at the south pole because one day they may evolve into a threat or a pest in the US.