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Astronomers See the Glow of a Boiling Planet

Posted by Soulskill on from the anybody-have-a-starship-for-sale dept.

The Bad Astronomer writes "For the first time, astronomers have detected the light from a 'super-Earth' exoplanet. The planet 55 Cancri e (with twice the radius and 8 times the mass of Earth) circles its host star every 18 hours, and is so hot it glows in the infrared. By observing in that wavelength, the astronomers measured the dip in light as the planet's glow was blocked by the star itself. This is the reverse of the usual method of detecting a planet as it blocks the light of its host star."

9 of 56 comments (clear)

  1. How cold do you think it needs to be ? by NemoinSpace · · Score: 5, Insightful

    Before it doesn't emit infrared radiation?

    1. Re:How cold do you think it needs to be ? by gman003 · · Score: 4, Informative

      It's not the peak - TFA states the planet's temperature is about 2700C. Which I would call "infernal".

      That does, however, explain how the IR emissions are high enough for us to detect here on Earth, light-years away - it's really, really, *really* hot.

    2. Re:How cold do you think it needs to be ? by blackhat1234 · · Score: 4, Informative

      According to the article (yes I know it's not cool to RTFA) it's "so close to the star that the surface temperature is probably around 2700C — or 4900F!"

    3. Re:How cold do you think it needs to be ? by dido · · Score: 4, Informative

      2700ÂC is not just infernal I'd think. That temperature is nearly half the temperature of the sun's photosphere (5500ÂC). Iron melts at 1538ÂC, and boils at 2862ÂC. There could be clouds of iron vapor and rains of molten iron there. If it had any kind of atmosphere it would likely be made up of iron and silicon vapor.

      --
      Qu'on me donne six lignes écrites de la main du plus honnête homme, j'y trouverai de quoi le faire pendre.
    4. Re:How cold do you think it needs to be ? by avgjoe62 · · Score: 4, Funny

      ...it's really, really, *really* hot.

      Yea, but it's a dry heat...

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      How come Slashdot never gets Slashdotted?

  2. Re:super-Earth? by Ironchew · · Score: 5, Informative

    The only planets larger than Earth in the Solar system are the gas giants, so a super Earth is just a designation for a planet more massive than Earth, but not a gas giant.

  3. Re:super-Earth? by Roger+W+Moore · · Score: 5, Informative

    What exactly justified it to be called super-Earth?

    Earth-like but significantly bigger than earth. The planet in question is 8 times the mass of Earth with twice the radius so roughly the same density. It might only be a factor of 8 in mass but if you saw a person with 8 times the average mass, say ~600kg, you'd certainly call them super-sized! As for temperature Venus is hotter than Earth but with a surface temperature of 460C it's decidedly nippy compared to the planet in question which is just over 1700C.

  4. Sauna world by circletimessquare · · Score: 5, Funny

    I suggest we send Finnish astronauts. They actually like this sort of place.

    "Cosmonaut Hämeenniemi! Have you reached the planet, what is it like!"

    (long delay)

    "Shhh... I'm relaxing"

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    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
  5. ^_^ by Anonymous Coward · · Score: 3, Funny

    A watched planet never boils...