Roy, from Newmarket asked:
When a meteor falls to Earth, does it break the sound barrier?
Dominic - Yes, it breaks the sound barrier – actually by a very long way. These meteors are typically travelling at 10.000-30,000 km/s when they impact the atmosphere [and sound only travels at 330m/s], so they’ll produce a massive shock-wave and you may hear a bang if the meteor is big enough.
Chris - A sonic boom?
Dominic - A sonic boom – yes, exactly! And in fact, if you have a large meteor, such as the one that hit Tunguska in 1909, it was the shock-wave that caused most of the damage rather than the object itself. The object would have been only a few tens of metres across, but the shock-wave it produced devastated an area of several square miles in Siberia.
Dave - I guess the reason why you don’t normally hear [sonic booms] for small shooting stars is they don’t get far enough down so the sound doesn’t reach you standing on the ground.
Dominic - Yes. And also - they’re very small objects, most shooting stars.
How big does a meteor have to be, to produce an audible sonic boom? Gem, Mon, 5th May 2014