The Milky Way is moving through space at two million kilometres per hour.
Why it is true
Our galaxy is pulled by the gravity of massive structures like the Great Attractor, travelling at a mind-boggling speed through the universe towards other galaxies.
Source: Astrophysics
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.