Ready for Touchdown
Getting ready for touchdown
But the next year, astronomers found a second object in a similar orbit, then another, and another. Instead of a
Yet many remained, and are still with us today: a small planet (and maybe more than one), icy planetesimals that
Not much in our lifetimes — perhaps 1 in 10,000 — but over thousands or millions of years, major impacts
What is the chance of Earth being hit by a comet or asteroid? Read More »
The truth behind the demise of the dinosaurs may never be fully resolved, but a growing body of evidence has
It depends on what exactly you think you see. If you believe you have discovered a new member of a
How do I report seeing unusual objects in the sky? Read More »