Mentor 1, 2, 3, 4, 5, 6 ('Advanced Orion 1, 2, 3, 4, 5, 6')

The Mentor satellites (name has been reported, but is not confirmed), which are generally known as 'Advanced Orion'), are geostationary signals intelligence satellites, which replaced the Magnum / Orion series. Their purpose is to intercept communications transmissions, especially line-of-sight microwave links and missile telemetry interception, from Russia and China.

The NROL 15 launch is suspected to be the sixth satellite in the Mentor series, but due to the higher power launch vehicle, a modified version is also possible.