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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."
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.
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.
Table-ized A.I.
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.
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.
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.
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)?
We are a LONG way from being able to recognize life. For all we know, other sentient life could be made entirely of energy. There's no way we would know if there was life. There's no way to rule out any possibilities. For all we know, there's a methane based life form on Titan.
The same goes for other Sentient life that's trying to find US. They might not even be able to see the correct spectrum of light to see us. Maybe they're based off of dark matter or something, or anything else we may not even be able to imagine. Maybe they live in 5 dimensions instead of our 4 (including time). Maybe they have 2 dimensions of time?
I fear the only way is to search for lifeforms that look like us, which might be a lot rarer then other types of life, and which we might never find.
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-Eddie
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.
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.
We now are finding lots of extra-solar planets, and have moved on to analzying some of their atmospheres. Is SETI really a "religion"?