Long Beach-based Virgin Orbit failed Monday on its 1st attempt to launch a test satellite into space aboard a rocket carried aloft by a Boeing 747 and released over the Pacific Ocean off the coast of Southern California.

The inaugural launch had appeared to be going well until moments after the LauncherOne rocket was dropped from beneath the left wing of the jumbo jet dubbed Cosmic Girl.

“We’ve confirmed a clean release from the aircraft. However, the mission terminated shortly into the flight. Cosmic Girl and our flight crew are safe and returning to base,” Virgin Orbit said in its official Twitter commentary on the launch.

There was no immediate word on what went wrong.

The highly modified jumbo jet took off from Mojave Air and Space Port in the desert north of Los Angeles and flew out just beyond the Channel Islands, where the drop occurred.

The rocket was supposed to fall for a few seconds before the 1st of its 2 stages ignited and hurtled it down the coast toward the South Pole for insertion of its demonstration payload into a low Earth orbit.

The purpose of the flight was to gather data on every step of the launch process rather than to have a useful satellite in orbit; the demonstration payload was described as an inert mass and the intended orbit was very low to avoid contributing to the problem of space junk.

The launch attempt followed 5 years of development of the 70-foot-long LauncherOne rocket.

The failure today comes after another attempt earlier this week that was aborted when a sensor warning prompted the team to scrub for the day “out of an abundance of caution.”

Virgin Orbit, headquartered in Long Beach, is a sister company of Virgin Galactic, the company Sir Richard Branson founded to carry passengers on suborbital flights into the lower reaches of space. Virgin Galactic is preparing to begin operations in southern New Mexico.