The details of the vehicle's latest mission are top secret, but that hasn't stopped an amateur astronomer from locating it.
Former UFO chief Dr. Sean Kirkpatrick has offered up a possible explanation for some military UAP sightings.
The object, which was only visible using thermal imaging cameras, seemed to have appendages dangling from its underside.
There is evidence to suggest that the satellite - named Kosmos-2558 - is tailing a confidential US satellite.
Former intelligence chief John Ratcliffe claims that the US has evidence of objects moving at extreme speeds.
The US military's secretive space plane is due to launch on May 16th with a cargo full of experiments.
The newest branch of the US military has taken delivery of its first weapon, but it's probably not what you think.
A 'jam-proof' communications satellite for the newest branch of the US military has successfully launched.
A fleet of drones has been making regular appearances over the last week and even the US military is mystified.
Key government officials have agreed on the importance of declassifying space-based US military projects.
The US military's notoriously secretive miniature space shuttle is back and nobody knows what it has been up to.
A US military Twitter account has issued an apology for threatening to bomb 'Storm Area 51' attendees.
The US military's secretive pint-sized spacecraft has now spent a whopping 717 days up in space non-stop.
According to FCC documents, the US military has been experimenting with a new type of mass surveillance.
1 million social media users who have pledged to storm the secretive base have been warned against doing so.
The US military's mysterious X-37B has spent almost a year in space on its latest secretive mission.
This brand new branch of the US military will aim to establish American dominance in outer space.
The private space firm succeeded in sending a top secret US military satellite in to orbit this morning.
Drone operators and other military personnel could have their effectiveness boosted by electrical pulses.
Scientists are developing a way to create an interface between a computer and a soldier's brain.