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First Exoplanet Atmospheres Analyzed

deblau writes "NASA's Spitzer Space Telescope has captured for the first time enough light from planets outside our solar system, known as exoplanets, to identify signatures of individual molecules in their atmospheres. The landmark achievement is a significant step toward being able to detect possible life on rocky exoplanets and comes years before astronomers had anticipated."

31 of 106 comments (clear)

  1. EPA by Tablizer · · Score: 5, Funny

    Shit! They are all polluted also.

  2. they can read the fine print by User+956 · · Score: 3, Funny

    NASA's Spitzer Space Telescope has captured for the first time enough light from planets outside our solar system, known as exoplanets, to identify signatures of individual molecules in their atmospheres.

    Jesus. If they can see that far out, imagine what they can see when they look straight down.

    --
    The theory of relativity doesn't work right in Arkansas.
    1. Re:they can read the fine print by flyingsquid · · Score: 3, Funny
      Jesus. If they can see that far out, imagine what they can see when they look straight down.


      NASA says that if you don't stop doing you-know-what, you're going to go blind.

    2. Re:they can read the fine print by Tackhead · · Score: 2
      > > Jesus. If they can see that far out, imagine what they can see when they look straight down.
      > NASA says that if you don't stop doing you-know-what, you're going to go blind.

      No, that's NSA, not NASA.

      (Keyhole cat is watching you masturbate, but he works for NRO, not the other two agencies ;)

    3. Re:they can read the fine print by iamlucky13 · · Score: 4, Informative

      I figured somebody better follow the joke up with some clarification. The optics on Spitzer, like Hubble, aren't focused that close. Plus it's infrared. Skin complexion would look like crap.

      Also, they aren't directly seeing the planet. I don't know if Spitzer's cameras could theoretically resolve it, but I do know it can't pick it out of the glare from its star. The method is to use a spectrograph and note really carefully the spectra of light received from the observation. When the planet, which is emitting light at different wavelengths depending on the molecules present, goes behind the star, this spectra changes ever so slightly. From this you know which portions of the spectra are from the star and which are from the planet, and you can deduce the molecules based on characteristic spectral lines.

      This is very much like colors on an LCD monitor. Let's say you have a switch that will let you turn off one pixel of a triad (the triad being the red, green, and blue pixels that make up a visible pixel), but you don't know what color it is. If you see a yellow pixel, you know there is actually a red pixel and green pixel turned on right next to each other, even though your eye can't resolve them. You flip the switch and the visible pixel turns red, so you know the pixel you control is green. The colors of the pixels are analogous to the molecules on the planet versus the star. The pixel you can control is like the planet, but instead of a switch it goes behind the star.

      Since the article apparently likes big numbers over useful units, the 370 and 904 trillion mile figures for the distances to the two observed targets are equal to 63 and 153 light years respectively.

    4. Re:they can read the fine print by Anonymous Coward · · Score: 2, Interesting

      I have it direct from a group of Hubble engineers that if the day side of earth ever gets in view of HST, it'll burn the camera out completely. The lenscap/door thing on the business end always opens toward earth for this reason.

    5. Re:they can read the fine print by ColaMan · · Score: 2, Informative

      Never mind - from a bit of online searching of some old archives, it would appear that Hubble's limit of focus is about 10000km -> infinity without adjustment. The range of adjustment needed to make in-focus observations of the ground is pretty small however (12mm or so), so it's quite possible that it could be done.

      But why you would do that when there are no doubt perfectly good spysats out there with better resolution, I don't know.

      --

      You are in a twisty maze of processor lines, all alike.
      There is a lot of hype here.
  3. Re:they have to replace pluto by Tablizer · · Score: 2, Funny

    they just have to replace pluto as a planet so they dont have to change every textbook ever made

    That newly-arrived large ominous black orb with the giant satellite dish embedded in it may qualify.

  4. So Our First Sign of Extraterrestrial Civilization by Phrogman · · Score: 3, Funny

    ... will be when we discover a planet with a huge hole in its ozone layer? :P

    --
    "The first time I got drunk, I got married. The second time I bought a chimpanzee, after that I stayed sober" Arian Seid
  5. Check their accuracy a year from now by PDMongo · · Score: 3, Interesting

    What will be really interesting will be to see how accurate their atmospheric analysis will be a year from now. In the article they mentioned finding tiny particles of "silicates in the atmosphere". Sounds a like a lot of speculation as to what the actual data could represent.

    --
    I've done the math, I know the odds, but I'm still disappointed when I don't win the lottery.
  6. Alien Infiltration? by Anonymous Coward · · Score: 5, Funny

    "The theorists' heads were spinning when they saw the data," said Dr. Jeremy Richardson of NASA's Goddard Space Flight Center, Greenbelt, Md.
    Better have some xenobiologists check those guys out. Or a priest.
  7. Re:they have to replace pluto by gardyloo · · Score: 4, Funny

    That newly-arrived large ominous black orb with the giant satellite dish embedded in it may qualify. Cartman became black?!?
  8. Subtraction works by Tablizer · · Score: 5, Interesting

    I think it is amazing how they can get the spectrum of the planet by substracting the spectrums of both using a formula like:

        planet = (star + planet) - star

    In other words, take the spectrum of both and compare it to the spectrum of the star when the planet is behind the star.

    It seems to me the star's spectra would be so strong as to wash out anything from the planet. However, maybe the specific chemical signatures they are looking for are weak in the star. For example, stars are probably too hot for a water line. Water would probably be converted into fundimental elements by the star.

    1. Re:Subtraction works by 1fitz2many · · Score: 3, Informative

      These data were taken in the mid-infrared, where the contrast between the star and the planet is not as great --- only about 200--300:1, instead of 10^6--10^10 to 1 in the optical/near-IR.

  9. Re:I for one by Original+Replica · · Score: 3, Funny

    Our exoplanetary overlords don't want our water. What would a sentient cloud of silicon crystals want with H2O? They are just trying to figure out if the silicon chips of our planet are willing to sell a few of their pet waterbags. (that's us)

    --
    We are all just people.
  10. Not earth like by rossdee · · Score: 4, Informative

    All the extra solar planets that have been found so far are large gas giant type planets.

    Our telescopes aren't good enough (yet) to detect small earth size rocky planets.

    While spectographic analysis of these planets atmosphere is interesting, it does not give us information about the possiblity of life (as we know it, Jim) since these aren't the places we would find life in this solar system either. Maybe these other planetary systems do include rocky planets, or moons (like titan and europa ) that could be candidates for some form of life, but we wouldn't find that out by looking at the atmospheres of JUpiter and Saturn

    1. Re:Not earth like by 1fitz2many · · Score: 5, Interesting

      There have been some recent discoveries of some "super-Earth" planets, e.g. GJ 876d and a planet found through gravitational microlensing, that have masses several times that of Earth. In the core-accretion scenario for planet formation, it's hard to stop runaway gas accretion once it gets going, suggesting that such low-mass planets are rocky and not gaseous. Perhaps they're the remnant cores of former gas giants that have lost their gaseous envelopes via some process that occurred after formation.

    2. Re:Not earth like by David_Shultz · · Score: 2, Interesting

      it does not give us information about the possiblity of life (as we know it, Jim) since these aren't the places we would find life in this solar system either.

      Even if we are only looking at gas giants, at the very, very least, wouldn't it help us better understand the chemical makeup of neighbouring solar systems, and aid in the development of more accurate models of solar system formation (which will in turn help us better understand the probability of life elsewhere a la Drake equation)? Isn't it also quite possible that knowing the chemical makeup of gas giants might provide evidence for the existence and makeup of nearby celestial bodies (given some model of solar system formation)? I am by no means well informed in the domain of solar system formation, but it seems just obvious that there would be some statistical correlations between the chemical makeup of the gas giants and the chemical makeup of the smaller planets that share a common star -is this totally wrong? Might it not also be the case that the number and makeup of gas giants will provide evidence for the number and makeup of smaller planets (again, given some model of solar system formation)?

  11. Nah, Just add a sticker... by Anonymous Coward · · Score: 2, Funny

    This textbook contains material on the planet Pluto. Classification of Pluto as planet is a theory, not a fact. This material should be approached with an open mind, studied carefully, and critically considered.

  12. Re:However, due to lack of federal support by MightyMartian · · Score: 4, Interesting

    That's not NASA's fault. That's the fault of greedy, whorish, self-serving Congressmen who, in place of a sense of vision and wonder, hold their proverbial genitals in their hands making idiotic demands upon the agency before they'll vote on funding. The ISS that was originally proposed would have been quite something. A space shuttle that actually followed the initial requirements would have been incredible. But by the time it was all filtered through the worthless filth that inhabits Washington, we were left with a pack of crap.

    --
    The world's burning. Moped Jesus spotted on I50. Details at 11.
  13. Nitpick by E++99 · · Score: 2, Informative

    I'm sorry, but they are not detecting the signatures of INDIVIDUAL MOLECULES. Try "individual compounds".

  14. Valuable by fishthegeek · · Score: 2

    I really think that the skills needed to analyze a distant planets atmosphere are important. But it doesn't matter what they discover, the information that the telescopes gather is billions of years old and is likely completely to be worthless for the purposes of planning exploration. It is still cool though.

    --
    load "$",8,1
    1. Re:Valuable by khallow · · Score: 2, Informative

      The more distant system is 150 lightyears away. Since that is also how much time it takes to light reach here, the data is "only" 150 years out of date.

  15. Maybe they're using the Smelloscope by Dachannien · · Score: 3, Funny

    Professor Farnsworth: Now, we all know telescopes allow us to see distant objects. But what if we want to smell distant objects? Well, now we can! Thanks to my new invention: the Smelloscope. The odor travels past this coffee stain here, around the olive pit, and into this cigar burn. And this appears to be a doodle of myself as a cowboy. But the Smelloscope is brilliant, I tell you! Think of the astronomical odors you'll smell, thanks to me.

  16. Not the First, Folks by CheshireCatCO · · Score: 2, Informative

    This is great research and all, but I would think that the people at Spitzer would be a lot more cognizant and courteous to their colleagues and not inflate their claims of priority. A team already analyzed the atmosphere of a transiting exoplanet using STIS on Hubble. It's a different situation (most exoplanets don't transit, after all), but they HST team did this around five YEARS ago. I remember hearing talks about it at the time, it was a big deal. Surely the Spitzer team should have known about this?

    1. Re:Not the First, Folks by Seanasy · · Score: 3, Informative

      If you RTA, they mention that Hubble was only able to identify elements in the atmosphere and was using a different technique. Spitzer is able to make out molecules.

  17. Beautiful and Sad by deboli · · Score: 2, Interesting

    It is beautiful to read about such a scientific achievement, the technology involved and the vision of the scientists that implement it. From the results obtained an article is written that appeals to "the man in the street" and light-years are converted into xx trillion miles. After that you get to the comment section and this is just depressing. We need to return to proper science articles even in the poplar press and general web sites and if some people are not able to follow they have a choice: get informed or stay ignorant.

  18. Re:So Our First Sign of Extraterrestrial Civilizat by David+Jao · · Score: 5, Interesting

    I think we'd be more amazed to discover a planet with an ozone layer, period.

    This is more true than probably most slashdotters realize. Ozone is the only chemical indicator of life that we can reliably detect across long distances.

    Ozone, unlike oxygen itself, has a strong absorption spectrum in the infrared wavelengths. A space-based infrared telescope (like Spitzer, but better) is exactly the right tool for detecting the presence of ozone. (A ground based telescope will not do, since infrared is absorbed by the atmosphere.) Finding ozone on a planet is just like finding oxygen -- the two compounds are so closely related that you can't have one without the other. And oxygen is a very volatile compound that reacts with almost anything else if you leave it alone. The only way for a planet to have free floating oxygen is if something on the planet is producing it.

    As far as we know, the only way to sustain an oxygen atmosphere on a planetary scale is with life. So, yes, finding ozone on a distant planet would be a very exciting discovery indeed.

  19. Time to look at the Drake Equation again? by olevy · · Score: 2, Interesting
    Thanks for mentioning the Drake equation. Slowly but surely we are chipping away at the variables in that famous equation. Michael Crichton gave a famous lecture harshly mocking the Drake equation (emphasis is mine):

    N=N*fp ne fl fi fc fL

    Where N is the number of stars in the Milky Way galaxy; fp is the fraction with planets; ne is the number of planets per star capable of supporting life; fl is the fraction of planets where life evolves; fi is the fraction where intelligent life evolves; and fc is the fraction that communicates; and fL is the fraction of the planet's life during which the communicating civilizations live. This serious-looking equation gave SETI an serious footing as a legitimate intellectual inquiry. The problem, of course, is that none of the terms can be known, and most cannot even be estimated. The only way to work the equation is to fill in with guesses. And guesses-just so we're clear-are merely expressions of prejudice. Nor can there be "informed guesses." If you need to state how many planets with life choose to communicate, there is simply no way to make an informed guess. It's simply prejudice. As a result, the Drake equation can have any value from "billions and billions" to zero. An expression that can mean anything means nothing. Speaking precisely, the Drake equation is literally meaningless, and has nothing to do with science. I take the hard view that science involves the creation of testable hypotheses. The Drake equation cannot be tested and therefore SETI is not science. ETI is unquestionably a religion. Faith is defined as the firm belief in something for which there is no proof. The belief that the Koran is the word of God is a matter of faith. The belief that God created the universe in seven days is a matter of faith. The belief that there are other life forms in the universe is a matter of faith. There is not a single shred of evidence for any other life forms, and in forty years of searching, none has been discovered. There is absolutely no evidentiary reason to maintain this belief. SETI is a religion.

    http://www.crichton-official.com/speeches/speeches _quote04.html

    We now are finding lots of extra-solar planets, and have moved on to analzying some of their atmospheres. Is SETI really a "religion"?

  20. Informative summary by Yvanhoe · · Score: 2, Informative

    Here are the informations missing from TFS :
    Two extrasolar gas giant upper atmospheres were observed by the Spitzer infrared sprectrometer. It revealed mainly silicate dust and no water. That bewildered scientists who take for granted that such planets contain a high quantity of water. They extrapolate that it must be present under the dust layer.

    --
    The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
  21. Re:So Our First Sign of Extraterrestrial Civilizat by Rei · · Score: 2, Informative

    Well, not necessarily. Oxygen (and thus ozone) can be produced in macroscopic scales abiotically. Some classes of water worlds should do this, for example. They don't have a surface that wants to oxidize, and if they're massive enough, they'll hold onto an oxygen atmosphere produced through photochemical means. Some moons in our solar system, like Europa, have tenuous oxygen atmospheres.

    Likewise, other chemicals that we're not used to would probably still scream out "life" to us. What if you saw an atmosphere rich in fluorine? That's even more reactive than oxygen. Might seem reasonable to consider that a marker of life -- just not LAWKI. Might not mean anything; there's a lot of potential inorganic that we don't know about.

    What about surface features instead of atmospheric ones? Leaves tend to reflect strongly in the 700-750 nm range. What if we have a surface that has sharp spectral features in that range? Could be an indicator. Might not be. What if there were sharp spectral signatures in other ranges that don't correspond to minerals that we'd expect to be on the surface? Perhaps there are lifeforms with different biochemistry. Perhaps it's just deposits of a mineral that we don't expect to be there.

    There are plenty of other potential biosignatures, and it's basically going to take having multiple biosignatures to make a compelling case for life.

    --
    "Who the hell is Nietzche? It's a question stupid people are asking." -- Newscaster, "Jesus Christ Supercop"