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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.

B--rian
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Script Kitty
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    Look at http://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"? – ProfRob Feb 28 '15 at 10:02
  • 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. – Script Kitty Mar 01 '15 at 17:03
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    I know what the greenhouse effect is, I want to know how your greenhouse coefficient is defined. – ProfRob Mar 01 '15 at 18:29
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    Related question. – Irigi Mar 14 '15 at 11:53
  • This should help, it utilizes the greenhouse coefficient http://phl.upr.edu/library/notes/surfacetemperatureofplanets –  May 14 '16 at 20:08
  • Here's an easy to use calculator, you will need to decide upon a greenhouse coefficient and enter one, it won't calculate the amount of greenhouse coefficient for you; only the result of the variables that you enter: http://www.astro.indiana.edu/ala/PlanetTemp/index.html -- A website that might give you a ballpark value to try is here: http://terraforming.wikia.com/wiki/Greenhouse_Calculator -- A tutorial on greenhouse effect is here: https://www.lpl.arizona.edu/~showman/greenhouse.html – Rob Jun 04 '18 at 16:19
  • See this reddit post and this paper – Nilay Ghosh Jul 09 '21 at 05:09

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