US Space Force to launch not-so-secret military spaceplane

A not-so-secret, secret reusable spaceplane operated by the United States Space Force is scheduled to lift off for its eighth mission on Thursday, Aug. 21, from the Kennedy Space Center in Florida.

Space Force is not disclosing the length of this upcoming mission or the exact time of the launch, but a Federal Aviation Administration advisory indicates that the launch window is between 11:40 p.m. ET on Thursday and 5:11 a.m. ET on Friday.

Built by Boeing, the X-37B Orbital Test Vehicle is an uncrewed, autonomous spacecraft that the U.S. military uses to test technology and conduct experiments in high and low Earth orbits. While the existence of the spaceplane is widely known, much of its activities are kept under wraps by Space Force, which doesn't announce its return to Earth until after the fact.

While it looks like a smaller version of the now-retired space shuttle, the X-37B can’t get into orbit without a boost. For this upcoming mission, it's hitching a ride on a SpaceX Falcon 9 rocket inside the rocket's fairing, a protective enclosure made of carbon composite that keeps it safe during the launch until it's ready to be released into orbit.

The X-37B is capable of spending years in space, with mission lengths usually between 12 and 24 months, and it returns to Earth like an airplane, gliding to a landing at sites on either the East or West Coast.

First launched in 2010, Space Force said the X-37B has spent more than 4,200 days in operation during its previous seven missions. So far, the spacecraft has flown more than 1.3 billion miles in orbit, with its longest stint in space being 908 days, according to Boeing.

While Space Force doesn't provide a lot of details about the X-37B's activities, they said this eighth mission will include "demonstrations of high-bandwidth inter-satellite laser communications technologies and enhanced space navigation using the highest performing quantum inertial sensor in space."

The military is interested in laser communications because it's considered more secure than traditional radio frequencies and can transmit more data than older technologies. The quantum sensor demonstrations will showcase how the spaceplane can navigate without using satellite networks like GPS. Instead of using accelerometers and gyroscopes, a quantum sensor measures rotation and acceleration at the atomic level.

In a press release, Space Force said, "These experiments come as part of a broader push across the U.S. Space Force to uphold the safety and security of the space domain by enhancing the resilience and flexibility of U.S. orbital systems."

Gen. Chance Saltzman, chief of space operations for Space Force, wrote in a message on the social media platform X, "This mission is about more than innovation. It’s about making our Joint Force more connected, more resilient, and ready to operate in the face of any challenge. That’s how America’s Space Force secures our Nation’s interests in, from, and to space."