I was given an exoplanet similar in size and distance to host star to our own earth. It's orbiting a star with luminosity six times our sun, the greenhouse coefficient 0.3, bond albedo 0.3.

I would like to calculate the approximate surface temperature (i.e. close enough to know whether it is in habitable range).

Disclaimer: This question was on a past exam and we never got our test back.

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    $\begingroup$ Look at en.wikipedia.org/wiki/Planetary_equilibrium_temperature The answer and necessary formula is given there. Actually, I just realised (and reversed my downvote of your question), that this does not incorporate your greenhouse effect.Can you define what you mean by "greenhouse coefficient"? $\endgroup$
    – ProfRob
    Feb 28, 2015 at 10:02
  • $\begingroup$ I think greenhouse factor reduces outgoing radiation from stuff like vapor in the air. The Earth's greenhouse coefficient is about 0.4 I think. I plugged the numbers into an open simulator and got a habitable range (it did not take into account 6x luminosity) and after plugging it into the equation it gives me a large amount of Kelvin. There are many variants of the equation. Thanks for your help. $\endgroup$ Mar 1, 2015 at 17:03
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    $\begingroup$ I know what the greenhouse effect is, I want to know how your greenhouse coefficient is defined. $\endgroup$
    – ProfRob
    Mar 1, 2015 at 18:29
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    $\begingroup$ Related question. $\endgroup$
    – Irigi
    Mar 14, 2015 at 11:53
  • $\begingroup$ This should help, it utilizes the greenhouse coefficient phl.upr.edu/library/notes/surfacetemperatureofplanets $\endgroup$
    – user11819
    May 14, 2016 at 20:08


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