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NASA's Spitzer Space Telescope wasn't

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designed to be an exoplanet super-sleuth

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but it's proving to be an amazing

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infrared detective tool Spitzer has

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split open the light from two alien

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worlds to planets outside of our solar

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system the resulting data called spectra

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reveal clues about their atmospheres we

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wanted to measure the spectrum of the

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planet because that tells us what

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molecules are present in the planet's

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atmosphere two different actually three

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different teams basically found the

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first real spectrum of a planet around a

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different star and that's a pretty big

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deal

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Grell mayer Swain and a third team

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headed by dr. Jeremy Richardson studied

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two planets HD 2094 58b and HD 1897 33 B

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- hot Jupiters or gas giants that orbit

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close to their Suns 300 to 900 trillion

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miles from Earth well you've heard the

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analogy that looking at a planet around

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another star is kind of like seeing a

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firefly next to a searchlight it's a

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very very faint object next to something

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extremely bright so how do you look at

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that in order to take this spectrum what

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we have to do is we have to let the

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planet be clipped by its star so we

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can't see the planet anymore and then we

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subtract the spectra that were taken

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inside of eclipse from the specter that

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were taken outside of Eclipse and then

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we're left with what the planet

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contributed

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some astronomers predicted there would

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have been water and to their surprise

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they found no hint of it in either

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atmosphere that could mean the water is

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hiding under a blanket of high clouds if

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the clouds are at high elevation they

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may just obscure the atmosphere of the

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planet the lower atmosphere where the

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strong water signature might exist I

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think it's premature to say

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Richardson's team however did spot

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something else

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silicon's there was a feature that we

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saw in the spectrum that is probably due

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to silicate mission and silicates are

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like molecules that have silicon and

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oxygen and typically some other metal in

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them and what that means is that that

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there's likely a cloud that's pretty

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high in the atmosphere that could be

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made of these silicate grains basically

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dust grains Spitzer astronomers hope to

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study the two planets more in the future

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and to use this technique on a handful

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of other transiting planets that orbit

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stars outside of our solar system I

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think this will ultimately be one of the

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most important legacies of the of the

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spitzer space telescope and

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unanticipated as it was before launch I

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think it will become extremely important

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in the future this is a stepping stone

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to eventually studying signs of life on

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worlds where life could exist the

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habitable worlds which were hoping to

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discover in the near future a step