Question: how large would you say is the largest and completely solid object in space be? or of what you have found so far?

Evan Keane answered on 22 Jun 2011:

This is actually a very difficult question to answer. It is very unusual to have a completely solid body. The Earth is not completely solid – it has liquid in the core. Same for the moon. Not sure if Mercury is totally solid (and don’t think anybody knows for sure yet). Venus is very similar in size to Earth so probably has some liquid interior too. I think Mars’ interior is not known for sure either. The other planets in our solar system are mostly gas. Stars are also just balls of gas, not solid. White dwarfs and neutron stars are pretty solid, although both of those have liquid interiors too. Black holes are not solid. On the small side of things asteroids and meteors are solid and comets are solid sometimes(when comets come close to the Sun the large amount of ice they contain melts).

Hmmm it is not possible to answer that question I think without specifying a few things. For instance how dense can something be before it is considered “solid”? If you up the density you can make something become liquid which might otherwise be a solid at that temperature.

My guess is one of the moons of Jupiter or Saturn which are bigger than Mercury might be totally solid, or if not, then Mercury, and if not Mercury then nothing is completely solid except the much small asteroids!

😀