Tracking information released by the U.S. military indicates two government payloads rode a SpaceX Falcon 9 rocket into orbit Dec. 19 on the NROL-108 mission, a dedicated launch for the National Reconnaissance Office.
The identities and purposes of the satellites remain top secret, but both spacecraft are presumably owned by the NRO, the U.S. government’s spy satellite agency.
The two spacecraft — publicly designated USA 312 and USA 313 — have been catalogued by the Space Force unit charged with tracking all satellites and space debris orbiting Earth.
While the military traditionally catalogs classified NRO satellites, officials typically do not publish each spacecraft’s orbital parameters, such as altitude or inclination.
However, amateur observers located one of the satellites within 24 hours of its launch from pad 39A at the Kennedy Space Center in Florida. Trackers around the world can locate NRO satellites via optical observations or through radio signals transmitted by the spacecraft.
A post to the SeeSat-L internet forum — where hobbyist satellite enthusiasts post their observations — by Dutch amateur radio operator Nico Janssen indicated a spacecraft from the Falcon 9 launch was tracked in an orbit between 322 miles and 334 miles (519-by-539 kilometers) in altitude. The object was orbiting with an inclination of 51.35 degrees to the equator, according to Janssen.
That orbit is similar to pre-launch predictions based on information about the Falcon 9 rocket’s ascent track toward the northeast from Florida’s Space Coast. That information, along with a re-entry zone for the launcher’s upper stage over the Pacific Ocean, was derived from warning notices for pilots to steer clear of the rocket’s trajectory.
The orbit does not match any of the NRO’s known surveillance or data relay satellite fleets, but it is somewhat similar to the orbit of a mysterious NRO payload launched in 2017 on a previous Falcon 9 flight. That spacecraft, designated USA 276, was deployed into a roughly 250-mile-high (400-kilometer) orbit at an inclination of 50 degrees. Only one spacecraft was catalogued from the 2017 launch.
As standard practice, the NRO does not disclose details about its satellite missions.
The mission Dec. 19, codenamed NROL-108, was the second SpaceX launch dedicated to the NRO. It was also SpaceX’s 26th and final Falcon 9 launch of 2020, a company record.
“NROL-108 carries a national security payload designed, built and operated by the National Reconnaissance Office,” an NRO spokesperson said in response to questions from Spaceflight Now. “Additional details about the payload and its mission are protected. The name or names of the contractor or contractors associated with building this payload is/are also protected.”
The NROL-108 mission did not appear on any public launch schedules until early October, when Spaceflight Now was first to report the existence of the mission. At that time, the mission was scheduled for Oct. 25, but the flight was delayed several times amid changing SpaceX launch schedules and other NRO launch activity at Cape Canaveral.
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