1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How hot is the sky?

  1. Jan 27, 2013 #1
    An object (a tin can for example) orbiting the Sun at about the same distance as the Earth would be what temperature?
  2. jcsd
  3. Jan 27, 2013 #2


    User Avatar
    Science Advisor
    Gold Member
    2017 Award

    This is really not a question about the sky is it :)

    the variation depends on if it is sunlit or shaded
    when you get away from any thermal influence of the sun or other body, ie. deep space, the temperature drops to the cosmic background radiation temp of ~ 4 K

  4. Jan 28, 2013 #3
    Sure it's a question about the sky. If the earth is at a stable temperature that means that it absorbs about as much energy from it's surroundings (the sky) as it emits.

    Earth is at thermal equilibrium with with it's surroundings (more or less), so when the tin can is in thermal equilibrium it will be at the same average temperature.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook