In Armageddon mission, Nasa to crash $330m spacecraft into asteroid to alter its course
The half-tonne probe will be travelling at more than four miles a second
Earth was hit by another huge asteroid at the same time as the one that wiped out dinosaurs, vast crater suggests
The new crater, nicknamed Nadir, appears to have been caused by something that would be comparably destructive on its own
NASA: Asteroid 2.3 times the size of dinosaur heading for Earth
Asteroid 2022 PW may be small, but it will fly dangerously close to the Earth, relatively close to the Moon's distance to the planet
