Armageddon outta here

In the August issue (325) I read about the exciting and potentially life-saving NASA and JAXA missions for the OSIRIS-Rex and Hayabusa2 space probes. But the possibility of mining asteroids gave me pause for thought. Is it possible that the change in composition and mass of the asteroid could affect its trajectory and bring about the very disaster we are hoping to avoid – namely a direct collision with Earth?

Jude Pountney, via email

It’s theoretically possible, but practically speaking, the distances involved are so incredibly vast that the change in mass needed to alter the asteroid’s orbit significantly would need to be impossibly huge. And the odds of ‘getting it right’, so to speak, by accident are astronomical (no pun intended). If you wanted to do it on purpose, however, that’s a different story…

– Daniel Bennett, editor