Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Earth As an Extrasolar Planet

timothy posted about 4 years ago | from the how-else-to-test dept.

Space 83

sciencehabit writes "Astronomers have a theory that they can detect whether a planet light years away will be habitable by just looking at how its sun is reflected in its atmosphere. To test the idea, they pretended that they were observing Earth from a distant object — in this case, the moon. And sure enough, they picked up critical components for life in Earth's atmosphere: ozone, oxygen, sodium, and nitrogen."

cancel ×

83 comments

Sorry! There are no comments related to the filter you selected.

Why not point Cassini back at us? (1)

Pikoro (844299) | about 4 years ago | (#33011820)

Why not point Cassini back at us and take some readings.. that should also give some good results.

Re:Why not point Cassini back at us? (3, Insightful)

Tablizer (95088) | about 4 years ago | (#33012010)

Cassini is probably not designed to be sensitive to those signatures. It's built for Saturn and co. It cost a lot to add & launch extra's outside of mission objective.

Re:Why not point Cassini back at us? (2, Informative)

st0nes (1120305) | about 4 years ago | (#33019170)

extra's

extras

Only works on eclipsed light. (5, Interesting)

pigeon768 (589860) | about 4 years ago | (#33012058)

This technique only works on light that passes through the planet's atmosphere. In this case, during a lunar eclipse, they pointing a telescope at the part of the moon that was reflecting the light that had traveled through the Earth's atmosphere. They found that the moon had absorption lines resulting from interactions with Earth's atmosphere.

The technique would work if the Earth occulted the Sun from Cassini's viewpoint, but such occultations are rare.

Re:Only works on eclipsed light. (0, Flamebait)

snowgirl (978879) | about 4 years ago | (#33012240)

This technique only works on light that passes through the planet's atmosphere. In this case, during a lunar eclipse, they pointing a telescope at the part of the moon that was reflecting the light that had traveled through the Earth's atmosphere. They found that the moon had absorption lines resulting from interactions with Earth's atmosphere.

The technique would work if the Earth occulted the Sun from Cassini's viewpoint, but such occultations are rare.

So... the light went through the Earth's atmosphere, into a reflector on the moon, which reflected it back... to the Earth's surface? Like... THROUGH the atmosphere that they were trying to detect anyways?

If it simply needed to pass through the atmosphere, I could do that in my back yard, why reflect it off the moon? Why involve anything other than a sensor on the Earth's surface? If "zomg, we have to be all mythbusters sciencey on this", then why not just a LEO satellite... each one, I'm sure receives more than enough light passing through the earth's atmosphere... I think it's like 16 sunsets a day, or something like that.

Seriously... cool science, cool results, but essentially just mast stroking...

Re:Only works on eclipsed light. (2, Insightful)

pigeon768 (589860) | about 4 years ago | (#33012298)

So... the light went through the Earth's atmosphere, into a reflector on the moon, which reflected it back... to the Earth's surface? Like... THROUGH the atmosphere that they were trying to detect anyways?

Yes. Part of calibrating a spectroscope involves adjusting for the fact that every result you'll ever get ever will have passed through Earth's atmosphere, and will demonstrate roughly the same absorption lines as a result. This is mitigated partially by the fact that spectroscopic analysis is usually performed somewhere at an observatory on the top of a mountain in some dry region with relatively stable weather, but considerations must still be made. Otherwise, every single star in the sky demonstrates molecular nitrogen and oxygen absorption lines - which would be surprising, to say the least.

This is usefulish science - one day, we may be in a situation where an Earth-like mass planet with an Earth-like orbit around a Sun-like star will occult. We have more information about what we need to do then.

Re:Only works on eclipsed light. (1, Informative)

Anonymous Coward | about 4 years ago | (#33013202)

We're finding a few planets like that with the kepler mission. I'm sure we'll have some spectroscopy results published this decade.

Re:Only works on eclipsed light. (1, Informative)

Anonymous Coward | about 4 years ago | (#33012336)

You miss the point, most sensors we have for detecting extrasolar planets are still placed within the atmosphere. What they simulated was detecting an earth-like planet placed two moon-distances away from earth trough the earth atmosphere.
Except for the distance beeing way too short by at least a factor of 10^10 this is something that could be useable.

Re:Only works on eclipsed light. (1)

snowgirl (978879) | about 4 years ago | (#33035834)

The technology and science necessary to make the equivalent observation of an extrasolar planet that we made of the Earth necessary requires a knowledge level that would circumscribe this technology.

In other words, "by the time we can actually make the detections necessary for the extrasolar case, we necessarily would have all the knowledge necessary to produce this test."

Which is kind of a retarded way of saying "we're going to have this technology first."

But having plenty of time left before it's even useful? Eh, a reasonable amount of criticism.

Basically, I suppose I object to this being NEWSWORTHY, rather than being science.

It's like those scientific tests that find that attractive people have more potential mates. Good science can be done, but it's hardly really stunning news that the public needs to be let known about.

Re:Only works on eclipsed light. (1)

BudAaron (1231468) | about 4 years ago | (#33013254)

More importantly it only applies to carbon based life I would assume. How about silicon based life - as an example?

Re:Only works on eclipsed light. (3, Insightful)

Jarik C-Bol (894741) | about 4 years ago | (#33013542)

yes of course, lets worry deeply about detecting (from light years upon light years away) a form of life that has only be theorized to be possible, and if exists is most likely in an environment that is totally incompatible with ours, thus making any contact with such life forms extremely difficult at best..

or you know, we could figure out how to detect life forms similar to our own, then try and branch out from that knowledge base once we accomplish that.

Re:Only works on eclipsed light. (1)

juasko (1720212) | about 4 years ago | (#33014892)

If you consider the complexity of life to even form and then consider the complexity of the planet + solar system to even support life.

Then consider what is the correct circumstances in a galaxy to allow such solar systems to emerge. And you find out that the possibility of life to spontaneously have started on those FEW! planets in our whole universe, you realize that is pathetic to search for extra terrestrial life.

Viewed in this perspective our universe is not huge at all though it's huge to us humans, still to small to contain enough planets for life to emerge on. And if there is life on an other planet in our universe I've would strongly consider that it was created.

But then few even see it that way, not even so called scientists. Those scientist should interest themselves of other science groups to actually se the whole picture. Math, Physics, Astronomy, Biology, Geology.

Just a few examples

The solar system needs to be at a certain distance from the galaxy core, why?

  1 ) Because if it's to close to the galaxy core radiation would kill any life that would have emerged the cosmic radiation would be to strong not even earth would be habitable in such condition. The distance would vary from galaxy to galaxy.

  2 ) If it's to far from the galaxy core there will not be enough matter to even form life. Eg, Iron would not be available and Iron is needed to form life and to protect life. A planet without a Iron core will not protect it's inhabitants from cosmic radiation that is totally hazardous to life. Earth has an iron core that generates a magnetic field that shields life on earth from most of the cosmic radiation.

The planet it self need to have it's temperature within a certain range to be able to inhabit life. It would also need to have a certain tilt ,as earth toward the sun, to be habitable. This tilt makes earth having a well temperated climate and allows life to exist around the whole globe. Without this steady tilt there would only be a small area where life could emerge on such a planet, and that area might move around and not be stable!

Then next Evolution should have actually started out which is full of "Which came first, egg or hen" paradoxes. Eg RNA,DNA and many others.

Nope, I do not believe in extra terrestrial life the possible amount of planets that have the right circumstances are way to few, and the possibility for evolution to happen on those few planets makes the chance for extra terrestrial life incredible small.

In my view this science is interesting as in how to find planets where we humans one day could exploiter on, but the searching for life on other planets is in my view totally pathetic and waste of time. I have once done the calculations based on some studies I have read and anyone can do them.

I'm not an scientist so don't take my word for it but, dig in to all those studies made on what makes life possible on earth and transform them into checkpoints of the environment that is needed on an extra terrestrial planet. And you'll see our huge universe is not huge at all it's small.

I don't say that such planets would not exist I believe they do but they are not enough in numbers to allow a second planet with life in our universe. Statistically out of the chart of possibility.

Re:Only works on eclipsed light. (1)

Antisyzygy (1495469) | about 4 years ago | (#33029610)

You fail to consider the option that extra-solar life could be completely dissimilar to anything on earth. Different metabolism, different nutritional needs, different respiratory gas, ect. ect. Also, your argument that life is so uncommon is flawed in that no-one actually knows how many of the trillions of stars out there have a reasonably stable planet in its orbit that could develop life. By "stable planet" I mean a planet that has a reasonable stable environment on it, free of random events like gamma ray bombardment or massive eruptions on short timescales like every million years or so. Even a planet that is constantly being bombarded by gamma rays can be considered "stable" since it must be possible to have life that is immune to such effects. Life could evolve such as a super hardy anaerobic bacteria or spore creature that uses gamma rays like plants use the sun, or hell, even something that isn't bacteria, nor virus, nor cell such as a mineral crystal that can self-replicate. Consider the fact that there are somewhere between 10^22 and 10^24 stars that are estimated, and that number is going up now that they have made a recent discovery that they cant even see a large part of the universe. Its hard to interject statistics into this since our sample size is 1, but I would wager my life that there is other life out there, but not necessarily intelligent ones.

Re:Only works on eclipsed light. (1)

juasko (1720212) | about 4 years ago | (#33066596)

I really doubt that life in univerce can have many different builds due to it's complexity in how it's buildt.

Anyway pathetic to serarch for it when there is now way to know how to search for it. And the posibility of finding life similar to ours is as earlier explained allready pathetic.

Only real use for this science is to know where we ourselves can one day settle down. I'm not against the science in it self, just find the strong believe in extra terrestial life out there pathetic, as the chances for it are so incredible minimal due to what i explained earlier.

No known protain is immune to cosmic radiation.

Re:Only works on eclipsed light. (1)

MokuMokuRyoushi (1701196) | about 4 years ago | (#33015722)

I believe(I may be reading this wrongly) this is for observing which planets might be habitable for humans. Sure, it would be a bonus to see if silicon-based life might have beat us there, but, not the objective. Seeing as we're carbon based.

Re:Only works on eclipsed light. (2, Interesting)

gstoddart (321705) | about 4 years ago | (#33021100)

More importantly it only applies to carbon based life I would assume. How about silicon based life - as an example?

You know, someone asks this in almost every thread where the search for extra terrestrial life comes up.

The reality of it is, we don't know anything about what a hypothetical silicon-based life-form would look like, or what kind of environment it would need.

Since we know nothing about this life-form, how do you propose we look for this? The simple answer is, we can't because we don't know what to look for.

When you don't have any actual testable hypotheses, it's simply not possible to conduct science. What you're describing is essentially science fiction since you start with the position that there must be silicon-based life and we should be looking for it.

Methinks you've watched too much Star Trek.

Looking for life that is similar to ours, we can at least say "well there is life on Earth which could live under those circumstances, so maybe there's something there". The whole point is to narrow the search, not needless widen it to conditions that, at present, represent nothing more than mere conjecture.

In short, searching for silicon-based life is currently futile and a waste of resources.

Re:Only works on eclipsed light. (0)

Anonymous Coward | about 4 years ago | (#33013376)

Not at all. Spectra from eclipsed and reflected light are complementary, if you know the one you know the other (in theory).

The Galileo probe already did this (4, Informative)

De_Boswachter (905895) | about 4 years ago | (#33012546)

"A search for life on Earth from the Galileo spacecraft", Nature, 1993 C. Sagan et al., http://www.nature.com/nature/journal/v365/n6448/abs/365715a0.html [nature.com]

Re:The Galileo probe already did this (4, Informative)

interactive_civilian (205158) | about 4 years ago | (#33013020)

For those without access to Nature, a Google Scholar search turns up a freely downloadable PDF of the full article.

PDF Link [uiowa.edu]

I remember reading about this in Sagan's "The Pale Blue Dot", and thought it was such an awesome idea. I'm looking forward to reading the original paper. :)

Just wondering (-1, Offtopic)

hyades1 (1149581) | about 4 years ago | (#33011830)

Now if they could only find an algorithm to distill out drunken assholes, perhaps they could even figure out whether intelligent life actually existed on these planets...

I'm pretending to leave a comment (-1, Offtopic)

OverlordQ (264228) | about 4 years ago | (#33011836)

Holy crap it showed up! It works!

fail (1)

OrangeTide (124937) | about 4 years ago | (#33017268)

You were never taught about pretending were you?

new life hard to predict (1, Insightful)

Anonymous Coward | about 4 years ago | (#33011870)

http://en.wikipedia.org/wiki/Jupiter#Possibility_of_life
http://www.youtube.com/watch?v=uakLB7Eni2E
http://www.thelivingmoon.com/41pegasus/02files/Critters_Carl_Sagans_Cosmos_Life_on_Jupiter.html

Besides extremophiles, there may entirely new systems of life.

co3Uk (-1, Troll)

Anonymous Coward | about 4 years ago | (#33011892)

This just in (5, Funny)

gmuslera (3436) | about 4 years ago | (#33011908)

NASA has finally proved that planet Earth is (still, at least) habitable! We knew that all that investment will bring us new knowledge some day.

Not NASA (2, Insightful)

pigeon768 (589860) | about 4 years ago | (#33012088)

Astrophysicist Alfred Vidal-Madjar and colleagues at the Institut d'Astrophysique de Paris decided to test the idea...

Granted, NASA does have the firepower and crack soldiering skills necessary to invade and occupy Paris, but they haven't done it. (yet)

Re:Not NASA (1)

Smooth and Shiny (1097089) | about 4 years ago | (#33012634)

Astrophysicist Alfred Vidal-Madjar and colleagues at the Institut d'Astrophysique de Paris decided to test the idea...

Granted, NASA does have the firepower and crack soldiering skills necessary to invade and occupy Paris, but they haven't done it. (yet)

I am happy to know that NASA has soldiering skills. That means we will be able to fend off any alien invasion for sure!

Re:This just in (1)

youn (1516637) | about 4 years ago | (#33012330)

Oh don't worry, we're working on it... we've been delayed by those green people... not the martians of course, the martians did a good job at turning their planet into a big desert :)... I wish they were still around so we could speed up the process :)... sheesh, saving the planet... what are they thinking?

Re:This just in (3, Funny)

Arancaytar (966377) | about 4 years ago | (#33012338)

Well, they needed a control experiment to compare their findings to when they prove otherwise in 20 years.

Re:This just in (1)

Kvasio (127200) | about 4 years ago | (#33015150)

NASA has finally proved that planet Earth is (still, at least) habitable! We knew that all that investment will bring us new knowledge some day.

now, if only we had means to find out if there is intelligent life.
Personally I doubt that.

Proving What (1)

MrOctogon (865301) | about 4 years ago | (#33011954)

From the moon, you have a pretty good view of earth. You can make out oceans and continents, and even manmade features if you have a good telescope. It looks like they focused on only measuring certain atmospheric things, but this proves nothing as far as extrasolar planets go. The distances involved make the earth-moon distance a piss-poor analogy for drawing any conclusions from this about anything light years away.

Re:Proving What (3, Informative)

MichaelSmith (789609) | about 4 years ago | (#33012040)

It looks like they focused on only measuring certain atmospheric things, but this proves nothing as far as extrasolar planets go.

Free oxygen on any planet tells you that something is making oxygen. In our case it is the plants which we treat so badly: turning them into newspapers, etc. Oxygen is so reactive that its presence tells you something must be going on. Mars used to have free oxygen but it combined with iron in the soil, turning it red: Iron Oxide.

Re:Proving What (1)

Yvan256 (722131) | about 4 years ago | (#33014554)

Mars used to have free oxygen but it combined with iron in the soil, turning it red: Iron Oxide.

So life originated on Mars, we screwed things up, were able to move to earth and now we're screwing things up again. Great.

Re:Proving What (2, Interesting)

buchner.johannes (1139593) | about 4 years ago | (#33017912)

It looks like they focused on only measuring certain atmospheric things, but this proves nothing as far as extrasolar planets go.

Free oxygen on any planet tells you that something is making oxygen. In our case it is the plants which we treat so badly: turning them into newspapers, etc.

The issue is burning down large areas of rain forest to get more short-term farmland, which uses up oxygen as well as permanently destroys the source for oxygen. The newspaper is not so relevant, since it is partially recycled and partially grown for the purpose.

You're very shortsighted (2, Insightful)

dreamchaser (49529) | about 4 years ago | (#33012168)

They are testing techniques for detecting elements that may signal the existence of life as we know it. You have to learn to walk before you learn to run.

If everyone had your attitude we'd still be living in caves and worshiping the spirits all around us.

Re:You're very shortsighted (2, Insightful)

snowgirl (978879) | about 4 years ago | (#33012216)

You have to learn to walk before you learn to run.

Right, but learning to walk is not the first steps towards crossing an ocean.

This test is trivial at best, because the data present themselves so readily. We can't even isolate extrasolar planets from their sun. Could we even detect this stuff from a more reasonable distance away. If this detects elements in the atmosphere, then we can use it on Venus, too, right? Which would be a lot more meaningful since it is relatively faint from the Earth surface, and LEO.

Not like much of this really means jack anyways, we already knew that elements absorb light in specific frequencies.

So, now to apply this to an extrasolar planet, we have to have the planet reflect the light of its sun back at the Earth, which means that their sun is already between them and us (counting "between" as being able to project the vector from here to their sun upon the vector from here to the extrasolar planet, and result in a vector of lesser magnitude than the vector from here to the extrasolar planet). And we're supposed to be able to isolate any of the light from that planet apart from its sun?

Most of the planets we can't even detect directly yet anyways.

So, yay! Someone tests a theory that will be completely non-applicable for at least decades. It's like having internal combustion engine before the wheel... mostly useless. (Yeah, I know the ICE uses wheel-type devices in it, leave me alone, it's supposed to be a lame analogy.)

Re:You're very shortsighted (0)

Anonymous Coward | about 4 years ago | (#33012308)

Venus

faint

...

Re:You're very shortsighted (1)

maxume (22995) | about 4 years ago | (#33012736)

As we speak, an optimistic slug is oozing his way towards a nice canoe-sized tree.

RTFA (3, Informative)

pigeon768 (589860) | about 4 years ago | (#33012892)

So, now to apply this to an extrasolar planet, we have to have the planet reflect the light of its sun back at the Earth, which means that their sun is already between them and us (counting "between" as being able to project the vector from here to their sun upon the vector from here to the extrasolar planet, and result in a vector of lesser magnitude than the vector from here to the extrasolar planet). And we're supposed to be able to isolate any of the light from that planet apart from its sun?

You misunderstand the experiment. For this idea to work, the planet has to be between us and the star. Exactly between - as in, the planet is eclipsing its sun, from our point of view. They're not detecting light that's been reflected off a planet, they're detecting light that's been filtered through a planet's atmosphere.

This is something we've already done [wikipedia.org] with large gas giant planets. The 'new' thing is that we did it with a planet the size of earth, with its significantly thinner atmosphere.

Re:RTFA (1)

snowgirl (978879) | about 4 years ago | (#33035904)

So, now to apply this to an extrasolar planet, we have to have the planet reflect the light of its sun back at the Earth, which means that their sun is already between them and us (counting "between" as being able to project the vector from here to their sun upon the vector from here to the extrasolar planet, and result in a vector of lesser magnitude than the vector from here to the extrasolar planet). And we're supposed to be able to isolate any of the light from that planet apart from its sun?

You misunderstand the experiment. For this idea to work, the planet has to be between us and the star. Exactly between - as in, the planet is eclipsing its sun, from our point of view. They're not detecting light that's been reflected off a planet, they're detecting light that's been filtered through a planet's atmosphere.

This is something we've already done [wikipedia.org] with large gas giant planets. The 'new' thing is that we did it with a planet the size of earth, with its significantly thinner atmosphere.

At twice the distance of the Earth and moon, I don't think the observable difference in thickness of the atmosphere is particularly significant. (I haven't done the math, but it strikes me as so.)

Even if there were a significant difference in the measurement required, then what? We've managed to prove that technology has gotten more precise at taking measurements? Whoopdidoo! Slow news day news!

Re:You're very shortsighted (0)

Anonymous Coward | about 4 years ago | (#33012562)

With that attitude we'd ALL be living in caves and worshiping spirits -- instead of just 40% of us.

Re:Proving What (1, Interesting)

Anonymous Coward | about 4 years ago | (#33012702)

uh, you do realize they were looking at the light reflected off the moon that was "coming" from earth ( light comes from sun to earth, bounces off, hits moon, and then they measured it, simulating a large distance since the moon is not super reflective (and neither is the earth)).

Re:Proving What (3, Informative)

murdocj (543661) | about 4 years ago | (#33012708)

The Slashdot summary was really, really bad. They didn't pretend to be observing the earth from the moon, they analyzed the spectra of light passing through the earth's atmosphere and reflected off of the moon. The idea is that this is similar to analyzing the light passing through a planet's atmosphere as it transits in front of a star. So it's not as crazy as it sounds.

What a waste of money (0, Troll)

LynnwoodRooster (966895) | about 4 years ago | (#33011982)

They could have just given me a few hundred thousand and I'd confirm for them that the Earth is hospitable for humans!

Re:What a waste of money (2, Funny)

Tablizer (95088) | about 4 years ago | (#33012022)

They could have just given me a few hundred thousand and I'd confirm for them that the Earth is hospitable for humans!

Until the point that American Idol and Fox News is detected ;-)
       

Narrow-minded folks (1, Insightful)

Anonymous Coward | about 4 years ago | (#33012052)

wHo says that life needs oxygen? Even on our planet are living beings who do not need oxygen at all. Black smoker bacterias for example.

Life develops according to outer circumstances. Darwin. Read it.

it's just plain stupid to believe extra-terrestial life can only develop on Earth 2.

Re:Narrow-minded folks (0)

Anonymous Coward | about 4 years ago | (#33012094)

I wouldn't call it stupid, it's just something that's easier to see since we understand it. We weren't looking for light in the non-visible spectrum until we knew it existed and understood better how to detect and interpret it, did we? Another reason for looking primarily for planets that have our building blocks is well.. because we might be able to go there.

Re:Narrow-minded folks (2, Insightful)

MichaelSmith (789609) | about 4 years ago | (#33012102)

People are chucking around the idea of life on Titan, with Hydrogen taking the place of Oxygen. The thing you have to look for is an environment out of balance. Plant life on Earth turns sunlight and carbon dioxide into oxygen. Our free oxygen gives the game away and would be obvious to a good telescope many light years away. I think we would look first for free oxygen, but other combinations would raise alarm bells too.

Re:Narrow-minded folks (5, Insightful)

cheesecake23 (1110663) | about 4 years ago | (#33012108)

wHo says that life needs oxygen? Even on our planet are living beings who do not need oxygen at all. Black smoker bacterias for example. Life develops according to outer circumstances. Darwin. Read it. it's just plain stupid to believe extra-terrestial life can only develop on Earth 2.

Thank God we have enlightened ACs teaching scientists how to do things! I'm sure they never considered the points you raised.

To address your point: they do NOT assume that life needs oxygen. However, the presence of significant amounts of oxygen in a planetary atmosphere is a strong indicator of life. This is because the gas is so reactive that it gets removed from the atmosphere very quickly. The only reason we have oxygen in our air is because it is continuously put there by photosynthesis.

Re:Narrow-minded folks (2, Funny)

deusx (8442) | about 4 years ago | (#33013306)

And besides, finding life that uses oxygen means we're more likely to find life similar to ours, so we can have sex with it.

Re:Narrow-minded folks (1)

Tablizer (95088) | about 4 years ago | (#33014728)

And besides, finding life that uses oxygen means we're more likely to find life similar to ours, so we can have sex with it.

But some days I'll settle for anything with suction cups.
   

Re:Narrow-minded folks (2, Insightful)

chichilalescu (1647065) | about 4 years ago | (#33012118)

they're not saying life can only develop this way. but if they find an earth-like planet, there's a pretty good chance it might have life. by the way, they're looking for habitable planets, not life.
the science of a class of systems "X" is always hard when you have just one example; there's no need to call them stupid.

Re:Narrow-minded folks (1)

Vahokif (1292866) | about 4 years ago | (#33012136)

Do you know any other characteristics we can look for?

Re:Narrow-minded folks (1)

PolygamousRanchKid (1290638) | about 4 years ago | (#33012212)

Do you know any other characteristics we can look for?

Porn? That's a dead give away that some hanky panky is going on . . . and where there is hanky panky . . . there is life.

So NASA should build some, um, probes, that detect porn on extrasolar planets. Then we'll know if there is really life there.

Probably . . .

Re:Narrow-minded folks (1)

LynnwoodRooster (966895) | about 4 years ago | (#33012296)

That's an easy problem to solve, just need to get a few of the investigators at the FTC to transfer over to NASA and we're set!

Re:Narrow-minded folks (0)

Anonymous Coward | about 4 years ago | (#33012376)

What would extraterrestrial porn look like?

Re:Narrow-minded folks (1)

khallow (566160) | about 4 years ago | (#33012538)

I'll field this one.

What would extraterrestrial porn look like?

You'll know it when you see it.

sodium (2, Funny)

Anonymous Coward | about 4 years ago | (#33012066)

It's natrium, you insensitive clod!

Re:sodium (1)

Tablizer (95088) | about 4 years ago | (#33014600)

My buddy and I nicknamed it "Nadium" in chem class to better match the periodic table symbols. One day one of us slipped and put it on a pop-quiz. It came back with triple red question marks.

Don't mix training and test data! (1)

cgenman (325138) | about 4 years ago | (#33012080)

So they take Earth, which has life, and use that to train up an algorithm to detect if other planets have life. Then they test this algorithm against... earth.

This is not how you're supposed to train systems. You need to keep your training and test data separate. Couldn't we have at least thrown one of those self-sustaining fish-globes up into space, and test that for life?

no training involved (1)

yyxx (1812612) | about 4 years ago | (#33013096)

The researchers formulated a hypothesis based on first principles ("training data"), then tested that hypothesis by applying it to earth ("test data"). So, they didn't mix training and test data.

Seems freakishly obvious... (0)

Anonymous Coward | about 4 years ago | (#33012556)

If you had asked me as a high-school student (15+ years ago) how to detect the makeup of a planet's atmosphere, my first guess would have been to check how light is refracted through, or reflected off, it. This seems like a "well duh" exercise to me. Am I missing something?

This is scientific heresy!!!! (0, Troll)

xmorg (718633) | about 4 years ago | (#33012588)

Take this off slashdot! It has no place in science! There are no other habitable planets! you are talking nonsense.

ummm (0)

Anonymous Coward | about 4 years ago | (#33012660)

Isn't that the same method they used in one of the Star Trek next gen episodes ..... its amazing how much science fiction ends up becoming science

WTF? (5, Funny)

mcneely.mike (927221) | about 4 years ago | (#33012662)

I for one welcome our new Earth overl-...... wait a second.....HEY, that's me!

Re:WTF? (0)

Anonymous Coward | about 4 years ago | (#33014322)

Not unless you're Jewish.

Not new at all (2, Interesting)

chebucto (992517) | about 4 years ago | (#33012676)

This is spectroscopy. They've been doing it for years, and it is the reason we know the chemical composition of everything from stars to planets to gas clouds. It's a fundamental tool of astronomy. The only novelty re: extrasolar planets is the resolution required, but even that isn't new, afaik.

The article quotes the boffin as saying

"The surprise was that we succeeded with extremely sparse observations under relatively bad weather conditions," Vidal-Madjar says. "But seeing how easily oxygen was seen strongly argues in favor of high-spectral-resolution searches [of Earthlike extrasolar planets]."

So it seems that the news here is that it's easier than expected to measure oxygen.

Gaseous Elements (-1, Troll)

pipingguy (566974) | about 4 years ago | (#33012750)

Was carbon dioxide detected? And while we're pretending, what life forms did they imagine to exist in a sodium and ozone environment (in addition to the N2 and O2, of course)? Could these imaginary life forms be carbon-based, or just some kind of woo-woo amazing aliens that have maybe possibly been visiting Earth for the past decades (well, since 1947) and probing innocent bystanders up the butt. Am I anti-science or ignorant/arrogant for demanding proof of aliens? So many questions.

How about (0)

Anonymous Coward | about 4 years ago | (#33013498)

We have the aliens snap a picture from their planet. You know... like when a tourist asks a stranger to take a picture of him with the missus?

Sodium? (1)

walter_f (889353) | about 4 years ago | (#33013630)

Hmmm.

Sodium (Na) a necessity in the atmosphere of a planet in order to make life (in a form similar to the one we know) possible?
If so, what about the minimal content of Tungsten (again, in a planet's atmosphere)? Barium, anyone's guess?

Just wondering...

Earth is heaven... (2, Interesting)

nulled (1169845) | about 4 years ago | (#33013730)

Now if only people, including Scientists of all fields, would realize that Heaven already exists and anyone that is alive is living in it. It is called planet EARTH.

No other place in the known universe has such a perfectly tuned atmosphere, able to support intelligent life. Let alone any type of life. Below is a list of traits the Earth has, which are rare, yet essential for life to spawn and be sustained.

1) A large moon to make stable the earths rotation (seasons), make oceans slosh which is said to have helped stir up the primordial soup to create chemical life.
2) A magnetosphere. Most planets/moons do not have one. Without one the atmosphere would blow away due to solar wind from the sun. Mars as an example.
3) In the goldie locks zone. Only Earth and Mars are known to exist in one, keeping water as a liquid. Not too close or far from the sun.
4) Orbiting a fairly stable Star called the SUN. Most stars are too large and burn out too fast.
5) Calm solar system, with very few cosmic impacts from comets/asteroids, allowing life to evolve and thrive in time for us to create anti-asteroid technology.
6) Earth is not too large or too small. If too small will cool down too fast and loss it's molten core and hence Magnetic Field. Example is Mars.
7) Jupiter did not ignite into a star. (Did not have enough mass) Yet, jupiter is large enough to vacuum up many objects that could have hit the Earth and killed us.
8) Large amounts of H20, carbons, Nitrogen, Iron, etc. Life needs a nice mix of elements to create an Atmosphere and life. Missing a key element and life would not be.
9) Solar system not too close to other stars/clusters to avoid Super Nova's and other hazardous stars which could kill us all.
10) Pure chance that anything else I missed that Earth has going for it to allow life to Evolve and invent technology to allow Internet and myself to type to YOU.

Now, you tell me if Earth is not a Heaven? Tell me that all of these things are not extremely good things to have happened to Earth and whether or not you think we are damn lucky yo even be alive. If not, you need to seriously consider looking into science more and learning about all the amazing things the Earth has going for it to allow you to exist at all.

We are all in Heaven as far as I am concerned. It was in front of our face the whole time, if one only puts down the ego and learns about these things.

Re:Earth is heaven... (1)

SheeEttin (899897) | about 4 years ago | (#33015518)

We evolved to make use of our environment. What makes you think life on other planets can't be, say, sulfur-based instead of carbon-based? (Yeah, something about carbon bonds with other elements, I know. It's an example.)
And why need an atmosphere at all? Burrow around in the crust, you'll do just fine. You just won't be respiring. Or swim in the ocean, and respire something other than oxygen. Say, hydrogen.

Sure, Earth is a paradise--but only if your concept of "life" is limited to what's on Earth.

Re:Earth is heaven... (1)

endymion.nz (1093595) | about 4 years ago | (#33016132)

Silicon forms many of the same types of bonds with other elements as carbon, you were probably thinking of that instead of sulfur. :)

Re:Earth is heaven... (0)

Anonymous Coward | about 4 years ago | (#33017302)

So you take all those astronomical odds, and multiply them together. Chance for a large moon (1/10000000) x chance of a magnetosphere (1/1000000) etc (numbers completely made up).

Now you take this damn-near-zero number and multiply it by the number of massive bodies in the Universe.

And that number that is damn near zero is now damn near 1.

Drake's Equation.

Re:Earth is heaven... (1, Informative)

Anonymous Coward | about 4 years ago | (#33017622)

1- We don't know how rare if at all for a planet like earth is to have a large moon, based in our solar system that may be the norm and Venus being the rarity.
2- Again, not true, mercury has one, earth has one, Mars had one, same with the non rocky planets, Venus being the exception.
3- by the actual sample of extrasolar planets it looks as if the goldie locks zone it is a good orbit for planets to form and as yourself mention our own solar system has two in that orbit
4-by the latest data it also looks as if single sol type stars are more numerous than expected, also nothing prevent much more stable stars e.g. red dwarfs to have planets
5-how rare is that, can you produce evidence that they are not common? and calling the solar system calm is also an overstatement with craters and impact marks all over the place and impacts happening even now.
7- again by the latest data it looks as if rocky planets are the norm rather than the exception.
8-those elements are as common as mug, we are detecting amino acids even in gas clouds.
9-Just like a few millions of stars around the periphery of our galaxy.
10-It did already happened several times on earth, we know of several extinction events, life seem to be very hardy once it takes hold and perhaps the earth may not be the best place for life after all, there may be better places elsewhere.

Re:Earth is heaven... (1)

nulled (1169845) | about 4 years ago | (#33018296)

I am not saying that another Earth is not possible.

In fact, I know there is one. The universe is infinitely huge, so the math says so.

What I am trying to say is that so far it is the ONLY planet we know of. We will not be traveling to any planets anytime soon. It takes light years to get to the nearest star. And the nearest star may not have planets.

Planet Earth may not be rare but it is very far to the next one. And no, Worm holes are not proven to exist. And if worm holes do exist there is no way to travel through one.

There is a chance we can travel near the speed of light and time will nearly stop, allow us to possibly get to distance places a possibility. Or even freezing our bodies in suspended animation. but, again, the technology is not there yet and may not be if ever.

To just assume there is another Earth and we can get there, is being incredibly niave and arrogant. Earth is our only home and may never be another one. To assume otherwise is complete egocentric nonsense.

Re:Earth is heaven... (1)

DigiShaman (671371) | about 4 years ago | (#33018346)

Most likely, life started in/around hydrothermal vents via a process known as chemosynthesis. Life in the universe might not be so uncommon so long as you have liquid water, geothermal energy, and necessary elements.

I'm a fossil! (0)

Anonymous Coward | about 4 years ago | (#33013884)

Originating on a planet that has an atmosphere of 78% Nitrogen, 21% Oxygen, and 1% other gases I am surprised at this discovery. Where is the Hydrogen? Where is the Carbon? Where did the Sodium come from? What happened to CHON!?

Maturana and Varela and Prigogine (1)

fritsd (924429) | about 4 years ago | (#33014534)

I think it was Maturana and Varela, but I can't for the life of me figure out where I left that book, who had the hypothesis that life has a tendency to modify its surroundings, so that the surroundings are subsequently more suitable for that life to exist.
Think about worms; they eat the earth, but in the process they make the earth more aerated and more suitable for worms to live in, as anyone with a compost heap can attest.
I think this ties in nicely with the idea of Ilya Prigogine that life is a process which is thermodynamically far out-of-equilibrium, i.e. a steady state: as long as you feed a lifeform (e.g. sunlight if it is a plant) it lives, but when it has no more food it dies, i.e. reverts to chemical equilibrium.
If you combine both ideas, you can get to the point I want to make:
  • Life on earth is in a constant state outside of (chemical) equilibrium
  • Life on earth modifies its surroundings to better suit it (20% Oxygen atmosphere and flammable plants!)
  • Therefore, a spectrogram of an planetary atmosphere with a composition that is out of chemical equilibrium is an indicator of life on that planet

It seems the gist of this article is a bit how occultation gives a good opportunity to take the spectrogram of a planet, but I think they missed saying why finding an out-of-equilibrium atmosphere is an indicator of possible extraterrestrial life.

Re:Maturana and Varela and Prigogine (1)

nulled (1169845) | about 4 years ago | (#33015742)

What you are trying to say is this...

Every one of us, (Humans, plants and animals) are connected. If one group dies, the rest will die as well.

Re:Maturana and Varela and Prigogine (1)

fritsd (924429) | about 4 years ago | (#33022022)

No.. not really what I meant.. more that, if everything would die, the composition and spectrum of our planet's atmosphere would become more boring, more like most planets, as it quickly goes to chemical equilibrium.
What you're saying, that we are all connected, is a bit more in line with James Lovelock's Gaia theory. I don't really know what to think of that. I think there is some ecological idea about "keystone" species [wikipedia.org] of ecosystems, maybe we're one of them.

earth as a replaceable commodity (0)

Anonymous Coward | about 4 years ago | (#33015036)

good luck with that.

meanwhile (seems like it's been way too long already); the corepirate nazi illuminati is always hunting that patch of red on almost everyones' neck. if they cannot find yours (greed, fear ego etc...) then you can go starve. that's their (slippery/slimy) 'platform' now. see also: http://en.wikipedia.org/wiki/Antisocial_personality_disorder

never a better time to consult with/trust in our creators. the lights are coming up rapidly all over now. see you there?

greed, fear & ego (in any order) are unprecedented evile's primary weapons. those, along with deception & coercion, helps most of us remain (unwittingly?) dependent on its' life0cidal hired goons' agenda. most of our dwindling resources are being squandered on the 'wars', & continuation of the billionerrors stock markup FraUD/pyramid schemes. nobody ever mentions the real long term costs of those debacles in both life & any notion of prosperity for us, or our children. not to mention the abuse of the consciences of those of us who still have one, & the terminal damage to our atmosphere (see also: manufactured 'weather', hot etc...). see you on the other side of it? the lights are coming up all over now. the fairytail is winding down now. let your conscience be your guide. you can be more helpful than you might have imagined. we now have some choices. meanwhile; don't forget to get a little more oxygen on your brain, & look up in the sky from time to time, starting early in the day. there's lots going on up there.

"The current rate of extinction is around 10 to 100 times the usual background level, and has been elevated above the background level since the Pleistocene. The current extinction rate is more rapid than in any other extinction event in earth history, and 50% of species could be extinct by the end of this century. While the role of humans is unclear in the longer-term extinction pattern, it is clear that factors such as deforestation, habitat destruction, hunting, the introduction of non-native species, pollution and climate change have reduced biodiversity profoundly.' (wiki)

"I think the bottom line is, what kind of a world do you want to leave for your children," Andrew Smith, a professor in the Arizona State University School of Life Sciences, said in a telephone interview. "How impoverished we would be if we lost 25 percent of the world's mammals," said Smith, one of more than 100 co-authors of the report. "Within our lifetime hundreds of species could be lost as a result of our own actions, a frightening sign of what is happening to the ecosystems where they live," added Julia Marton-Lefevre, IUCN director general. "We must now set clear targets for the future to reverse this trend to ensure that our enduring legacy is not to wipe out many of our closest relatives."--

"The wealth of the universe is for me. Every thing is explicable and practical for me .... I am defeated all the time; yet to victory I am born." --emerson

no need to confuse 'religion' with being a spiritual being. our soul purpose here is to care for one another. failing that, we're simply passing through (excess baggage) being distracted/consumed by the guaranteed to fail illusionary trappings of man'kind'. & recently (about 10,000 years ago) it was determined that hoarding & excess by a few, resulted in negative consequences for all.

consult with/trust in your creators. providing more than enough of everything for everyone (without any distracting/spiritdead personal gain motives), whilst badtolling unprecedented evile, using an unlimited supply of newclear power, since/until forever. see you there?

"If my people, which are called by my name, shall humble themselves, and pray, and seek my face, and turn from their wicked ways; then will I hear from heaven, and will forgive their sin, and will heal their land." )one does not need to agree whois in charge to grasp the notion that there may be some assistance available to us(

boeing, boeing, gone.

are we visible with gravitational lensing? (0)

Anonymous Coward | about 4 years ago | (#33015070)

Recently we have begun finding extrasolar planets using gravitational lensing. Would this technique work for aliens to see the planet Earth?

Check for New Comments
Slashdot Login

Need an Account?

Forgot your password?

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>