DSP 22

USA / US Air Force

Spacecraft n:

USA satellite n:

Defense Support Program satellite
Also known as IMEWS-22, USA 176 or DSP 3-9

Launch data:

Designation 28158 / 04004A
Launch date 14 Feb 2004 - 18:50 UT
Launch site CC, SLC-40
Launch vehicle  Titan-402B/IUS (#4B-39)
Mission Military: Early warning
Geostationary orbit:
Perigee / Apogee 35741 x 35832 km
Eccentricity 1.08E-03
Inclination 1.41°
Period 1436.12 min

DSP-14 satellite

To provide early warning of missile and space launches, as well as nuclear explosions.
Titan 4B-39 placed the IUS-10 upper stage in parking orbit; two IUS solid motor burns put DSP-22 into geostationary drift orbit. The Titan second stage remains in low orbit, the IUS SRM-1 motor in geostationary transfer orbit, SRM-2 in geostationary drift orbit. The DSP satellite's infrared telescope cover was presumably ejected a few days later, and the satellite is being placed on station to observe missile launches. This was the 24th and last use of the Boeing IUS upper stage since the first IUS launch in 1982; a 25th stage, IUS-23, was never flown. The final DSP will be launched on a Boeing Delta 4.

Spacecraft data:

Prime contractor Northrop Grumman's Redondo Beach
operation (formerly TRW)
Operator US Air Force
Mass at launch  2380 kg
Dry Mass  kg
Basic shape  
Dimension  6.7 m dia x 10 m long (deployed)
Solar array  
Stabilization  spin stabilized
DC power  1485 W
Design lifetime  7-9 yrs - still active


 April 2010 103.84° E 

Probably downlinks in S- and X-band. Has a wide field infrared telescope to provide real-time warning of missile launches (6000 infrared detectors).

An artist's concept shows the DSP riding atop the IUS booster. Credit: Northrop Grumman

Mission details:

Infrared sensors to detect heat from missile and booster plumes against earth's background; detection capability of smaller missiles; improved warning of attack by short-range missiles against U.S. and allied forces.

Ref.: #3(SD380), #7(JR521), #15, #226 - update: 19.05.10 Home