USA-229

USA-229, known before launch as NRO Launch 34 (NROL-34), is a pair of American signals intelligence satellites which were launched in 2011. They are operated by the United States National Reconnaissance Office.

USA-229

Names	NROL-34 NRO Launch 34 NOSS-3 5A and 5B Intruder 9A and 9B
Mission type	SIGINT
Operator	United States NRO
COSPAR ID	2011-014A
SATCAT no.	37386 and 37391
Spacecraft properties
Spacecraft	NOSS-3 5 (3rd Generation)
Spacecraft type	Intruder
Bus	NOSS-3
Manufacturer	Lockheed Martin
Launch mass	3250 kg (each)
Start of mission
Launch date	15 April 2011, at 04:24 UTC
Rocket	Atlas V 411 (AV-027)
Launch site	Vandenberg, SLC-3E
Contractor	ULA
Orbital parameters
Reference system	Geocentric orbit
Regime	Low Earth orbit
Perigee altitude	1015 km
Apogee altitude	1207 km
Inclination	63.46° [1]
Naval Ocean Surveillance System ← USA-194 USA-238 →

Both satellites were deployed by a United Launch Alliance Atlas V 411 launch vehicle, which launched from SLC-3E at the Vandenberg Air Force Base. The launch occurred at 04:24 UTC on 15 April 2011.^[2] The rocket placed the satellites into a low Earth orbit. By 04:29 UTC, official updates on the status of the spacecraft had been discontinued.^[3]

Whilst details of the satellites and their missions are officially classified, amateur observers have identified that the Atlas V deployed two satellites, one of which has officially been catalogued as debris. The two spacecraft have been identified as being a pair of third or fourth generation Naval Ocean Surveillance System satellites.^[4] Amateur observations have located the spacecraft in an orbit with a perigee of 1,015 kilometres (631 mi) and an apogee of 1,207 kilometres (750 mi), inclined at 63.46° to the plane of the equator.^[2] Current generation NOSS satellites are always launched and operated in pairs,^[5] and are used to locate and track ships and aircraft from the radio transmissions that they emit.^[6]