🛰️ SATELLITE · CATALOGUE RECORD
USA 521
In orbitUSA 521 (NORAD 63596, COSPAR 2025-077A) is a US satellite in orbit, launched on 16 Apr 2025 on the NROL-174 Asterion mission. It is catalogued as [NRO Unk Smallsat 15]. It is operated by NRO as part of the NRO TS programme. The spacecraft was built by BALL? on the BCP-2000? bus, with a mass of 250 kg. No current orbital elements are published for it, so it is not shown on the live map or in pass predictions. Catalogue record from Orbital Radar's satellite archive, cross-referenced with the live satellite catalogue.
2025
launched
1
year on orbit
250
kg mass
Lifecycle
Launched16 Apr 2025 · on the NROL-174 Asterion mission
StatusOn orbit (not live-tracked)
Specifications
NORAD ID63596
COSPAR2025-077A
TypeSatellite
OperatorNRO
Country / StateUS
ManufacturerBALL?
BusBCP-2000?
Mass250 kg (200 kg dry)
ProgrammeNRO TS
CategorySIG?*
OrbitLEO (LEO/I)
Altitude1,097 × 1,124 km
Inclination63.4°
Frequently asked questions
What is USA 521?
USA 521 is a satellite launched in 2025 that is still in orbit. No current orbital elements are published for it, so it is not shown on the live map or in pass predictions.
Who operates and built USA 521?
USA 521 is operated by NRO and built by BALL? (US).
Launched together
Catalogue record from the Orbital Radar satellite archive. Sources & methodology: data sources. Accessed 2026-10-21.