Solid as a Rock? Porosity of Asteroids

Observations from NASA Spitzer Space Telescope, taken in infrared light, have helped to reveal that a small asteroid called 2011 MD is made-up of two-thirds empty space.

Observations from NASA Spitzer Space Telescope, taken in infrared light, have helped to reveal that a small asteroid called 2011 MD is made-up of two-thirds empty space.

AsteroidSpitzer Space Telescope