spaceSpace and Physics

The Secretive X-37B Space Plane Is About To Blast Off On A Mysterious Mission

You can watch a live stream of the SpaceX rocket launch from Florida tonight.


Tom Hale


Tom Hale

Senior Journalist

Tom is a writer in London with a Master's degree in Journalism whose editorial work covers anything from health and the environment to technology and archaeology.

Senior Journalist

The X-37B after its landing at NASA’s Kennedy Space Center Shuttle Landing Facility on November 12, 2022, at 05:22 a.m.

The X-37B after its landing at NASA’s Kennedy Space Center Shuttle Landing Facility on November 12, 2022, at 05:22 am.

Image credit: US Space Force

The secretive X-37B space plane is set to blast off today onboard a SpaceX rocket. Its mission? As ever, it’s not quite clear. 

For its seventh mission, the robotic plane will be launched on a SpaceX Falcon Heavy rocket for the first time, according to the US Space Force. The launch from NASA’s Kennedy Space Center in Florida was initially set for December 7, but it was postponed until December 11 during a 10-minute launch window that opens at 8:14 pm ET.


The lift-off will be live-streamed, so keep your eyes out for a video on SpaceX’s account on X (previously Twitter).

SpaceX’s Falcon Heavy is one of the world's most powerful rockets in operation and is essentially three Falcon 9 rockets strapped together. It’s not certain why this launch needs the extra oomph of the Falcon Heavy, but it might indicate the X-37B is loaded with a heavier payload than previous missions.

The US Space Force was typically vague about the nature of its mission, noting only that it would be “experimenting with future space domain awareness technologies, and investigating the radiation effects on materials provided by NASA.” 

The X-37B looks a bit like the iconic Space Shuttle, albeit a little more beaten up. It’s also much smaller, measuring 8.9 meters (29 feet) in length with a wingspan of just under 4.5 meters (15 feet). It’s capable of cruising in low-earth orbit, between 240 to 800 kilometers (150 to 500 miles) above the Earth, at speeds of up to 28,200 kilometers (17,522 miles) per hour.


Developed by Boeing, the autonomous craft has been the subject of six previous missions since 2010. The last of these concluded in November 2022 and involved its longest stint in orbit yet: a record 908 days.

The official line from the US military is that the X-37B performs “risk reduction, experimentation, and concept of operations development for reusable space vehicle technologies.” However, the precise details of its job are not certain. 

One of the leading theories is that it plays a role in spy craft and reconnaissance. Heather Wilson, former US Secretary of the Air Force, has previously said that the X-37B spacecraft can also turn and change its course when it’s at a lower altitude, suggesting it could be used to meddle with foreign adversaries. 

"[This] means our adversaries don't know – and that happens on the far side of the Earth from our adversaries – where it's going to come up next. We know that that drives them nuts. And I'm really glad about that," Wilson told a panel at the Aspen Security Forum in July 2019.


According to a BBC report on an article published in Spaceflight magazine in 2012, X-37B's orbit closely followed that of China's former space lab, Tiangong-1, leading to suggestions that it could have been used for space-to-space surveillance. Other experts have since denied these claims, however.

A slightly more sober suggestion came in October 2014 when security experts told the Guardian that the X-37B was being used "to test reconnaissance and spy sensors, particularly how they hold up against radiation and other hazards of orbit."

Well, I guess that settles it then...


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