Asteroid disaster downgraded, thank the deity
A few years ago, my younger brother and I were watching some program about the end of the world on Sci-Fi (which is now SyFy, apparently?), and space-as-cool-jazz man Neil de Grasse-Tyson said into the camera that an asteroid is going to pass so close to the Earth that it will be closer than most of the satellites we’ve got up there. It will be less than 1/12th the distance of the Earth to the Moon. It’s gonna be tight.
Then, this miserable death rock is going to slingshot ’round the sun and come back at us and there is a chance that, then, WHAM! It’ll smack right into us. Planetary bruising.
Well, thankfully, it’s looking less likely, says the Bad Astronomer:
How does this work? The orbit of an asteroid is calculated using measurements of its position in the sky over time. There is a tiny uncertainty in those positions for many reasons: atmospheric distortion blurring the asteroid image being one of if not the biggest. The way to minimize that is to get lots of images so that the errors average out, but even then the orbit calculated has uncertainties. And the longer into the future you project the orbit, the worse it gets. In the case of Apophis, astronomer Dave Tholen used hundreds of new images of Apophis to refine the orbit and get the better statistics for its impact risk.
Crisis averted, everyone! I’m a hero. No need to panic.
More info here.
