Pentagon's X-37B Space Plane Set For Sunday Launch; Mission Details Remain Undisclosed

The specific details of X-37B missions continue to be classified, including a NASA project onboard.

Pentagon's X-37B Space Plane Set For Sunday Launch; Mission Details Remain Undisclosed

Pentagon's X-37B space plane at NASA's Kennedy Space Center on May 7, 2017.

The US is preparing its mysterious X-37B space plane for its seventh launch. It's expected to be its longest and highest flight yet. This secretive plane has already spent 3,774 days in orbit across six prior missions, with the last one lasting a record 908 days. For five of those flights, it was launched on Atlas V rockets, while the sixth used a SpaceX Falcon 9.

According to The Washington Post, the veil of secrecy over the X-37B continues ahead of its launch Sunday at 8:14 pm Eastern on its seventh mission. But this time, there are some clues that at least something is different. The drone, which flies without anyone on board, is to be launched for the first time on SpaceX's powerful Falcon Heavy, which is more powerful than the rockets that have launched it in the past. That's led to speculation that the mission will be in a much higher orbit, which appears to be the case according to recent documents. SpaceX won the $130 million contract for the launch in 2018.

The mission has "a wide range of test and experimentation objectives," according to the Pentagon's official statement. "These tests include operating the reusable spaceplane in new orbital regimes and experimenting with future space domain awareness technologies."

The reference to "space domain awareness" could mean that it will be keeping an eye on other satellites, potentially watching for threats. Having a better sense of what is going on in the vastness of space-where adversaries' spacecraft are and what they are doing-has become a key mission of the US Space Force, reported the newsportal.

"Our space systems are threatened by a variety of growing antisatellite capabilities, and the joint force is threatened by increasingly sophisticated adversary space-based systems intended to target the joint force," General Chance Saltzman, the Space Force's chief of space operations, said in a statement to Congress earlier this year.