One doesn’t typically think of spacecraft as UAS, but they are. Most are one way, but an X-37B just returned to earth after two years in space.
The Boeing X 37B, an unmanned space orbiter that looks like a small version of the space shuttle, returned from a 718 day secret space mission that began back in May 2015. It apparently created a sonic boom as it came into Cape Canaveral for a landing. It is launched using United Launch Alliance’s Atlas 5 rocket.