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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."
I've got nothing
Its difficult to survive on resources in a time zone after you expire. But I guess its fun to look anyway..
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.
Science made a mistake? Since when is that supposed to happen? Lololol
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.
Fail troll is FAIL
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.
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!
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
Science makes a mistake? Who knew?
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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
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.
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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
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.
Our moon itself is barren yet we are so close ... I still don't understand.
"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?
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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.
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!
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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.
"In that case, the universe is very severely fucked." We already knew that. The universe at large is very hostile to life, has enormous distance filled by pretty much nothing. Anthropic principle , my ass.
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.
Hortas are the children of the Flying Spaghetti Monster. They just have smaller meatballs.
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