The Sun and Moon appear to be the same size because the moon is 400 times smaller than the Sun, but 400 times closer to Earth.
13
All of the Earth's continents are wider at the north than in the south - and nobody knows why.
194
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
Pluto is smaller than Russia.
9
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
If two pieces of metal touch in space, they become permanently stuck together.
808
The Earth gets heavier each day by tons, as meteoric dust settles on it.
118