Vela 1B was one of two spin stabilized (2.1 rev/sec) 134-kg satellites comprising the first launch in a series of six Vela launches. The orbits of the two satellites on each launch were basically circular at about 17 earth radii and were spaced 180 deg apart. Their objectives were to monitor nuclear weapons explosions in space and to study x-rays, gamma-rays, neutrons, and charged particles as the satellites passed through interplanetary space, the bow shock, the magnetosheath, and the magnetotail. The satellite operated in either a real-time mode (one data frame/sec) or a memory store mode (one data frame every 256 sec). The spacecraft was operated in the real-time mode about 40 percent of the time and in the store mode for the rest of the time until the next Vela launch. At this time, tracking priority was given to the new spacecraft, and the older spacecraft was operated in the store mode only. There had been less and less data coverage of these satellites with each succeeding launch.



X-Ray/Charged Particle
Not Available

Gamma-Ray/Charged Particle
Not Available

Neutron Detector
The neutron detector was designed to monitor neutron signals from the nuclear explosions in space and to establish background characteristics for neutron detectors exposed to neutrons and showers produced in the spacecraft by cosmic rays. The detector used a large polyethylene moderator to thermalize incident neutrons, the thermal neutrons were detected in two helium 3-filled proportional counters. Each counter had its own power supply and amplifier to afford greater reliability. Neutrons in the approximate range 1 - 100 MeV were counted and read out each second. The detector also reacted to (but did not distinguish) protons greater than 25 MeV in energy, thus it provided a simple indication of solar proton activity. The experiment worked well over the period of major data coverage.

Launch-Orbit Information

Launch Date: 1963-10-17
Launch Vehicle: Atlas-Agena D
Launch Site: Cape Canaveral, United States
Mass: 150.0 kg