The Colorado-based company is aiming to build a Concorde-like supersonic aircraft—but has hurdles to clear before realizing that goal.

A prototype of a passenger jet designed to succeed the supersonic Concorde broke the sound barrier for the first time on Tuesday above the Mojave Desert in California. Why it matters: Exceeding Mach 1 speed — 770 miles per hour — is an important milestone in the quest by Boom Supersonic,