AKA: DSV-2C;SLV-2A;SLV-2C;Thor Agena D SLV-2A/D;Thrust Augmented Thor. Status: Retired 1968. First Launch: 1963-02-28. Last Launch: 1968-01-17. Number: 61 . Thrust: 1,571.00 kN (353,174 lbf). Gross mass: 67,819 kg (149,515 lb). Height: 31.00 m (101.00 ft). Diameter: 2.44 m (8.00 ft). Apogee: 1,000 km (600 mi).
First launch of a triplet of Poppy naval signals intelligence satellites, which would lead to the NOSS production series. Official and secondary mission: Gravity gradient stabilization tests. Space craft engaged in investigation of spaceflight techniques and technology (US Cat A).
The 100th Thor/Agena, a Thrust Augmented Thor/Agena D (421/1170) was launched from Vandenberg AFB by the 6595th ATWg. KH-4A. Primary mode of recovery failed on second portion of the mission (1011-2). Small out of focus areas present at random on both cameras.
First test of a side-looking radar from outer space. The mission lasted only four days, as planned, before the batteries ran out of power during orbits 72-73. The radar operated 14 times in orbit, between 22 and 26 December, imaging swaths of the northeastern and western United States. Data collected from the 14 radar passes were transmitted over a wideband (UHF) data link as they were obtained ("real time") to the Vandenberg or New Boston ground station in view. In addition, during the first seven radar passes data were recorded on film on board the satellite, and on 23 December, during the 33rd orbit, the reentry capsule was jettisoned and recovered. The vehicle and payload performance were within acceptable limits on all parameters. The radar maps covered about 80,000 square miles and the resolution was better than 15 feet in azimuth and 80 feet in ground range. The mission, not declassified until 2012, proved the feasibility of space-based surveillance, leading to the operational Lacrosse satellites of the 1980's.
OGO 2 was a large observatory instrumented with 20 experiments designed to make simultaneous, correlative observations of aurora and airglow emissions, energetic particles, magnetic field variations, ionospheric properties, etc., especially over the polar areas. Soon after achieving orbit, difficulties in maintaining earth lock with horizon scanners caused exhaustion of attitude control gas by October 23, 1965, 10 days after launch. At this time, the spacecraft entered a spin mode (about 0.11 rpm) with a large coning angle about the previously vertical axis. Five experiments became useless when the satellite went into this spin mode. Six additional experiments were degraded by this loss of attitude control. By April 1966, both batteries had failed, so subsequent observations were limited to sunlit portions of the orbit. By December 1966, only eight experiments were operational, five of which were not degraded by the spin mode operation. By April 1967, the tape recorders had malfunctioned and only one third of the recorded data could be processed. Spacecraft power and periods of operational scheduling conflicts created six large data gaps so that data were observed on a total of about 306 days of the 2-yr, 18-day total span of observed satellite data to November 1, 1967. The spacecraft was shut down on November 1, 1967, with eight experiments still operational. It was reactivated for 2 weeks in February 1968 to operate the rubidium vapor magnetometer experiment.
The PAGEOS (Passive Geodetic Earth Orbiting Satellite) spacecraft was a 30.48-m inflatable sphere, and had no instrumentation on board. It was the second (following GEOS 1) NASA satellite in the National Geodetic Satellites Program. The launch, orbit, separation, inflation and initial operation were nominal, with more than 40 ground stations participating in the observation program. The orbit was generally considered too high for drag-density study, although some work was done in this area by the Smithsonian Astrophysical Observatory. Additional Details: here....
OGO 4 was a large observatory instrumented with experiments designed to study the interrelationships between the aurora and airglow emissions, energetic particle activity, geomagnetic field variation, ionospheric ionization and recombination, and atmospheric heating which take place during a period of increased solar activity. After the spacecraft achieved orbit and the experiments were deployed into an operating mode, an attitude control problem occurred. This condition was corrected by ground control procedures until complete failure of the tape recording systems in mid-January 1969. At that time, due to the difficulty of maintaining attitude control without the tape recorders, the attitude control system was commanded off, and the spacecraft was placed into a spin-stabilized mode about the axis which was previously maintained vertically. In this mode, seven of the remaining experiments were turned off since no meaningful data could be observed by them. On October 23, 1969, the satellite was turned off. It was reactivated again in January 1970 for 2 months to obtain VLF observations.
The last scheduled Air Force Thrust Augmented Thor/Agena (SLV-2A //498/SS-01B #2733) to be launched from Vandenberg AFB was the 150th Thor/ Agena vehicle fired from there since Discoverer I was launched on 28 February 1959. From now on, the Air Force would use the more advanced Long Tank Thrust Augmented Thor (SLV-2G) - Thorad - and the newer SLV-2H.