Was that boom a fireball?
The bright fireballs US Government sensors saw, and where each one's sonic boom could reach the ground.
Fireballs, last two years
Heard a boom? Check it
Enter when and where. We look for a listed fireball and for rocket launches that could explain it.
Why fireballs boom Mach 40 to 200, low enough for the shock to reach the ground.
A meteoroid enters the air at 11 to 72 km/s, forty to two hundred times the speed of sound. Most burn up above 60 km, where the air is too thin for a boom to be heard. Larger ones survive deeper, below about 50 km, and their shock wave reaches the ground as a sharp boom or a rumble, one to several minutes after the flash: sound needs that long to come down from 20 to 50 km.
How the map works Rays traced from the luminous path; strength from weak-shock theory.
For every fireball with a known speed and direction, shock rays leave the luminous path below 60 km almost at right angles to it and are traced through the standard atmosphere until they reach the ground or turn back up. The coloured dots are where they land. Strength comes from ReVelle's weak-shock theory for a line source, sized from the impact energy; it is good to a factor of about 3, checked against the 2013 Chelyabinsk fireball.
Limits No wind, no hills; only the big fireballs are listed.
- The atmosphere is the standard one, with no wind: the real edge of the zone moves with the weather of that night.
- The fireball's end height is assumed a little below its brightest point; fragmentation and the terminal burst are not modelled.
- CNEOS lists only the largest events. For the rest, report what you saw and heard to the American Meteor Society.
Data: NASA JPL CNEOS fireball data (US Government sensors, public). Method and code: engine/bolide.py. Privacy.