US military’s X-37B robot spaceplane blasts off on secret mission aboard SpaceX rocket

The US military’s secretive X-37B robot spaceplane has blasted off from Florida on its seventh mission, the first launched atop a SpaceX Falcon Heavy rocket capable of delivering it to a higher orbit than ever before.

As on previous missions, there’s no one on board the reusable plane, which resembles a mini space shuttle and carries classified experiments.

The Falcon Heavy, composed of three rocket cores strapped together, took off from NASA’s Kennedy Space Center at Cape Canaveral more than two weeks late because of technical issues, the Guardian reports.

Three earlier countdowns were aborted due to poor weather and unspecified technical issues, leading ground crews to roll the spacecraft back to its hangar before proceeding with Thursday’s flight.

The launch came two weeks after China’s robot spaceplane, known as the Shenlong, or “Divine Dragon,” was launched on its third mission to orbit since 2020, adding a new twist to the growing US-Sino rivalry in space.

The Pentagon has disclosed few details about the X-37B mission, which is conducted by the US Space Force under the military’s national security space launch programme.

Thursday’s launch marked the seventh flight of an X-37B, which has logged more than 10 years in orbit since its debut in 2010.

The last flight, the longest one yet, lasted two and a half years before ending on a runway at Kennedy a year ago.

The planned duration of the latest X-37B mission has not been made public, but it will presumably run until June 2026 or later, given the prevailing pattern of successively longer flights.

Built by Boeing, the X-37B resembles Nasa’s retired space shuttles but they’re just one-fourth the size at 29 feet (9 metres) long. No astronauts are needed; the X-37B has an autonomous landing system.

They take off vertically like rockets but land horizontally like planes, and are designed to orbit between 150 miles and 500 miles (240 kilometres and 800 kilometres) high.