This article contains orbital elements but does not include an epoch, or date when those elements, which typically vary over time, were correct. Please help by adding the epoch for the current data, or changing the orbital elements to ones with a known epoch.
The satellite's orbit and mission are officially classified, however like most classified spacecraft it has been located and tracked by amateur observers. It is in a Molniya orbit with a perigee of 1,111 kilometres (690 mi), an apogee of 37,580 kilometres (23,350 mi), and 63.5 degrees of inclination. In addition to its SIGINT payload, USA-200 also carries two secondary instruments; the SBIRS-HEO-2 missile detection payload as part of the Space-Based Infrared System programme, and NASA's TWINS-2 or TWINS-B magnetospheric science instrument as part of the TWINS programme.
Payloads are separated by bullets ( · ), launches by pipes ( | ). Manned flights are indicated in bold text. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in brackets.