Peter Jenniskens

A pebble the size of a grape enters the atmosphere almost tangentially and skims across the sky without falling. That's exactly what happened to a meteoroid weighing about 45 grams. It came in at such a shallow angle that it traveled 164 kilometers at an altitude of 92 kilometers — where the air is a million times thinner than at the surface.

A stone thrown into water quickly loses speed. A meteor entering the atmosphere should behave the same way: air slows it down, and friction burns up its material. But cameras of the Global Fireball Observatory network have captured hundreds of bright fireballs over ten years that streak across the sky with almost no deceleration.