Please consider donating to Behind the Black, by giving either a one-time contribution or a regular subscription, as outlined in the tip jar to the right. Your support will allow me to continue covering science and culture as I have for the past twenty years, independent and free from any outside influence.
Some results from the HTV-2 hypersonic flight: the glider flew successfully for about three minutes at 20 times the speed of sound.
Fixed the stupid error. The speed of SOUND is of course correct. Sorry for the lapse in thought.