Sound doesn't travel in space.
255
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
There are 5 to 10 times more stars in the known Universe than there are grains of sand on all the world's beaches, but a single grain of sand has more atoms than there are stars in the known Universe.
20
Pluto is smaller than Russia.
9
There's a mysterious dwarf planet between Mars and Jupiter called 'Ceres' which has never been visited by spacecraft or photographed in detail, however, Earth-bound telescopes reveal a large bright shining spot on the surface of this planet, the origin and nature of which are unknown.
5
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
It 'snows' metal on Venus.
13