Heating gasses in space -- How could we make a greenhouse in space?

[jakehussey]

TL;DR

How could we make a greenhouse in space. Thought experiment!

I was thinking the other day about green houses and how they would act in space or on another planet without an atmosphere. I know that green houses work on Earth by stopping convection but could they theoretically trap heat in a non atmospheric environment? I am imagining a material that allows short wave radiation in and traps long wave from escaping. My assumption is that a gas would have to be used such as CO2 but how could I calculate actual heat generated and how much gas is required?

 

[russ_watters]

Greenhouses also block some radiation - longer wavelength, and the emitted radiation is longer than the avsorbed. But what's the point of a greenhouse in a vacuum?

 

[DaveC426913]

I suppose we are being biocentric. There could be valid reasons for wanting to passively warm a volume that have nothing to do with living critters.

 

[jakehussey]

I suppose we are being biocentric. There could be valid reasons for wanting to passively warm a volume that have nothing to do with living critters.

Yes Dave. My initial thought was a passively warm volume in a simple structure on another planetary body for keeping equipment warm or heating substances.

 

[DrClaude]

Why use a gas? Why not an actual greenhouse?

 

[Arjan82]

Well, I guess the Earth is a sort of greenhouse in the vacuum of space...