Transit Research and Attitude Control

The Transit Research and Attitude Control (TRAAC) satellite was launched by the U. S. Navy from Cape Canaveral along with Transit 4B on November 15, 1961.

Transit Research and Attitude Control (TRAAC)
Artist's impression of TRAAC in orbit
Mission typeTechnology
OperatorUnited States Navy
Harvard designation1961 Alpha Eta 2
COSPAR ID1961-031B Edit this at Wikidata
SATCAT no.205
Mission duration270 days
Spacecraft properties
Launch mass109 kilograms (240 lb)
Start of mission
Launch dateNovember 15, 1961, 22:26 (1961-11-15UTC22:26Z) UTC
RocketThor DM-21 Ablestar
Launch siteCape Canaveral LC-17B
End of mission
Last contactAugust 12, 1962 (1962-08-13)
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Semi-major axis7,405.20 kilometers (4,601.38 mi)
Perigee altitude958 kilometers (595 mi)
Apogee altitude1,109 kilometers (689 mi)
Inclination32.44 degrees
Period105.8 minutes
EpochFebruary 7, 2014, 04:46:58 UTC[1]
Drawing of the transit 4B and TRAAC satellite in orbit.


The 109 kg satellite was used to test the feasibility of using gravity-gradient stabilization in Transit navigational satellites.[2] It provided information on the effects of radiation from nuclear explosions in space, as it was one of several satellites whose detectors provided data for the Starfish Prime test; ultimately its solar cells were damaged by the radiation and it ceased operation.[3] It was among several satellites which were inadvertently damaged or destroyed by the Starfish Prime high-altitude nuclear test on July 9, 1962 and subsequent radiation belt. It is expected to orbit for 800 years at an altitude of about 950 kilometers (590 mi).


The first poem to be launched into orbit about the Earth was inscribed on the instrument panel of TRAAC. Entitled Space Prober and written by Prof. Thomas G. Bergin of Yale University, it reads in part:

And now 'tis man who dares assault the sky...
And as we come to claim our promised place, aim only to repay the good you gave,
And warm with human love the chill of space.[4]


  1. ^ "TRAAC Satellite details 1961-031B NORAD 205". N2YO. February 7, 2014. Retrieved February 7, 2014.
  2. ^ "TRAAC". Gunter's Space Pages. Retrieved October 7, 2007.
  3. ^ Hess, Wilmot N. (September 1964). "The Effects of High Altitude Explosions" (PDF). National Aeronautics and Space Administration. NASA TN D-2402. Retrieved November 28, 2017.
  4. ^ "Space Quotes". Space Educator's Handbook. NASA. Archived from the original on December 13, 2012. Retrieved October 7, 2007.