Any information on the interior of Phobos?

Whenever I try to look it up, I get this lame information on this conspiracy theory that the interior of Phobos is some sort of alien civilization....
Is it really hollow? And if not, what does it really look like on the inside?

1 Answer
Oct 17, 2017

It's not completely hollow.


It's believed to be more like a pile of smaller rocks loosely packed together by their own gravity. Such a body is called a rubble pile. In an estimate of 30% porosity is given.

Rubble piles are commonplace among small bodies such as asteroids, and Phobos itself may be a captured asteroid. Larger bodies tend to have enough gravity to smash or melt the rocks together into a solid body.