Summer on Uranus lasts for 21 years.
358
All of the Earth's continents are wider at the north than in the south - and nobody knows why.
194
The Earth gets heavier each day by tons, as meteoric dust settles on it.
118
Venus is the only planet that rotates clockwise.
310
The Space Shuttle main engine weighs 1/7th as much as a train engine but delivers as much horsepower as 39 locomotives.
147
The Earth gets 100 tons heavier every day due to falling space dust.
673
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