The US military’s Boeing-built X-37B spaceplane is in space again for its eighth mission.
The X-37B is an uncrewed craft that, just like the USA’s retired Space Shuttle, launches on a rocket and after re-entry makes an unpowered landing on a terrestrial runway. The vehicle has engines it can use to maneuver in space, but in 2024 deliberately grazed Earth’s atmosphere by “aerobraking” to make a significant change to its orbit.
It’s thought the spaceplane has other means to change its orbit – a move that requires a lot of energy – and is therefore the subject of occasional criticism from China on grounds it could be a weapons platform.
Little is known about the missions flown by the X-37B, save that they sometimes last for more than a year and nearly always involve experiments with new space technologies.
The craft launched again last week, atop a SpaceX Falcon 9, and this time Boeing had a a little to say about the mission, namely that on this flight the spaceplane:
- Includes a Boeing integrated service module to increase payload capacity for experimentation activities on orbit; >
- Is hosting several technology demonstrations from government partners on this mission, include laser communications and a quantum inertial sensor designed to support navigation when GPS is unavailable.
Boeing tested that quantum GPS tech in March 2025, when it described it as involving a “using a six-axis quantum inertial measurement unit (IMU” that use “a quantum-sensing technique called atom interferometry to detect rotation and acceleration using atoms.”
The USA’s Sandia National Laboratories have described atom interferometry as “an ultra-precise way of measuring acceleration” and built a “high-performance silicon photonic modulator — a device that controls light on a microchip” to put it to work.
The nub of the matter is that atom interferometry can be used to measure position – the same job we use GPS for today.
Which brings us back to why China is a bit antsy about the X-37B: Beijing worries it could take out its Beidou satnav satellites. The US worries about losing GPS satellites too, as modern warfare relies on them.
This X-37B flight therefore takes on a little more significance, as it’s testing a tech that could allow future spacecraft – and aircraft and who knows what else – to find their way even if satnav systems succumb to … something.
The Pentagon’s not said when it expects the X-37B back on Earth, or what it hopes to achieve with this mission. ®