Enlarge / Virgin Galactic's VSS Unity spacecraft launches on Saturday. (credit: Virgin Galactic)

On Saturday, the VSS Unity space plane made its final flight, carrying four passengers to an altitude of 54.4 miles (87.5 km) above the New Mexico desert. The spacecraft will now be retired after just seven commercial space flights, all made within the last year.

Although the flight was characterized by its chief executive Michael Colglazier as a "celebratory moment" for Virgin Galactic, the company now finds itself at a crossroads.

After an impressive but brief flurry of spaceflight activity—seven human spaceflights in a year, even to suborbital space, is unprecedented for a private company—Virgin Galactic will now be grounded again for at least two years. That's because Colglazier and Virgin Galactic are betting it all on the development of a future "Delta class" of spaceships modeled on VSS Unity.

Enlarge / Virgin Galactic's VSS Unity rocket plane ignites its rocket motor moments after release from a jet-powered carrier aircraft high above New Mexico. (credit: Virgin Galactic)

Last year, Virgin Galactic seemed to finally be hitting a stride toward making commercial suborbital spaceflight. The company flew its SpaceShipTwo rocket plane to the edge of space six times in six months, giving a few Virgin Galactic customers a taste of spaceflight after waiting more than a decade.

Finally, it appeared that Virgin Galactic turned a corner, moving past the setbacks and course corrections that delayed founder Sir Richard Branson's aim of bringing spaceflight to a wider population. Virgin Galactic officials wouldn't describe the company's next step as a setback or a course correction. It's part of an intentional business strategy to make Branson's dream a reality.

"That dream behind Virgin Galactic came into sharp focus as we repeatedly flew spaceship Unity in 2023," said Michael Colglazier, Virgin Galactic's president and CEO, in a quarterly earnings call this week. "Now, in 2024, we're poised for even more meaningful accomplishments as we build the fleet of spaceships that will turn the dream into reality and long-term success."