NASA and Lockheed Martin's experimental X-59 aircraft has broken the sound barrier, achieving a speed of Mach 1. 1. The feat could set the stage for "quiet" supersonic flight.
Source: [Live Science](https://www.livescience.com/space/space-exploration/nasas-experimental-x-59-jet-breaks-sound-barrier-for-1st-time-in-step-toward-quiet-supersonic-technology)