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Message: <blockquote data-quote="Loren Pechtel" data-source="post: 5858084" data-attributes="member: 4679">I said it's too cool to raise the planet to a habitable temperature, not that it emitted no heat.Lets say the brown dwarf is "glowing" at 500 degrees F.  Where does the planet have to be in order to stay above freezing?That's about 1/2 the temperature of the surface of the star.  (You have to do this on an absolute scale--Kelvin or Rankin.)  Emitted energy goes up at the 4th power of temperature.  1/2 the temperature = 1/16th the energy.  Therefore the star must comprise 1/16 the sky of the planet.  Obviously half the sky is night, this means the star must be 1/8th the day sky.Now, you could orbit close enough to a planet to do that but stars don't have anything like a defined surface, you're going to be in it's outer atmosphere and you'll spiral in from drag.I don't understand how they avoid the atmosphere freezing out on the dark side.If the atmosphere is thick enough it can shield the planet from the radiation.  Note that you'll get something of a disk around a neutron star, also.  It's just not as energetic.Any degenerate body with a nearby planet is going to be hot (or have a hot disk at least) due to infalling matter.  It's just they're going to be small enough not to contribute much in the way of light to the planet.</blockquote>