Mars had an oxygen-rich atmosphere around 4 billion years ago
13
A neutron star (what remains after a Super Nova) is so dense that a portion of it the size of a sugar cube would weigh as much as all of humanity, or more than all the cars in the United States.
5
Saturn's moon, Mimas, not only looks like the Death Star, it also has a Pac Man heat signature.
15
Jupiter is bigger than all the other planets combined.
254
It takes a photon 170,000 years to travel from the core of the Sun to the surface, but only 8 minutes to travel the rest of the way to Earth.
6