Sept 9 1975
From The Space Library
Viking 2 was successfully launched at 2:39 pm EDT from the Eastern Test Range on a Titan-Centaur launch vehicle. The spacecraft entered on a trajectory toward Mars accurate to within the 3sigma tolerance. If flown without midcourse correction, Viking 2 would reach Martian orbit 279 259 km from the target.
The launch had been rescheduled from 1 Sept., after the launch crew during a 28 Aug. precountdown test discovered a degradation in the detection threshold of the orbiter's S-band radio receiver. On 1 Sept., project officials decided to remove the spacecraft from the launch vehicle for additional evaluation. The launch was rescheduled for 9 Sept. after evaluation concluded that the anomaly had been caused by a faulty connector or conductor between the diplexer module and the high-gain antenna. Since the faulty part could not be isolated, the antenna and cabling were replaced, the orbiter and lander retested, encapsulated, and mated to the launch vehicle. After launch, all onboard systems and experiments were checked out. A trajectory correction maneuver on 19 Aug. targeted Viking 2 for a rendezvous with Mars on 7 Aug. 1976.
Viking 2 was the second of two identical planetary probes [see 20 Aug.], each consisting of an orbiter and a lander, launched toward Mars in 1975 for rendezvous and orbital and surface exploration in 1976. (NASA MOR S-815-75-01-02, 16 Sept 75; Viking Science Activities rpt no. 89; Mission Operations Status Bulletins 10-14)
Japan's N booster launched, from Tanegashima launch site, its first payload-Kiku, an 83-kg spacecraft designed to measure launch vibrations and spacecraft temperatures in space. Kiku entered orbit with a 1104-km apogee, 977-km perigee, 106-min period, and 47° inclination. The launch vehicle consisted of a Rocketdyne MB-3 first-stage engine, modified from the U.S. Thor program, with three Thiokol Corp. Castor 2 solid-rocket strap-ons. The second stage, designated LE-3, had been designed by Japan's National Space Development Agency with Rocketdyne assistance. The third stage was a Thiokol TE-364-4 solid-rocket motor. (GSFC Wkly SSR, 4-10 Sept 75;Av Wk, 22 Sept 75, 50)
A star tracker, STELLAR (Star Tracker for Economical Long Life Attitude Reference), was being developed by Jet Propulsion Laboratory for a variety of future manned and unmanned space missions. STELLAR used a solid-state silicon detector, called a charge-coupled device (CCD), for image sensing and a microcomputer to process and format the data. Previous star trackkes had used high-voltage vacuum-tube image dissectors for image sensing; the tubes were difficult to produce, had a limited lifetime, developed errors, and could provide attitude-reference data from only a single star in any given observation frame. STELLAR, which substituted a single low-voltage 6-mm-sq CCD chip for the complex and expensive tube, offered the advantages of solid-state reliability and of simple programming to adapt to varying mission requirements. In addition to substantial savings in cost of flight hardware, the CCD imaging devices were expected to revolutionize TV camera design, permitting miniature low-cost home monitors within the next several years.
STELLAR, which had been developed under the management of NASA's Office of Aeronautics and Space Technology, would provide trackers for planetary Mariner spacecraft after the Mariner-Jupiter-Saturn mission in 1977 and for such Space Shuttle payloads as the proposed Shuttle infrared telescope facility. For the telescope facility, STELLAR would track as many as 10 stars simultaneously, providing position coordinates and star magnitudes for each. (NASA Release 75-251)
The aft fuselage for Space Shuttle Orbiter 101 arrived at Rockwell International Corp.'s Palmdale, Calif., assembly facility after a 160-km truck journey from Rockwell's Downey plant. The aft fuselage joined the midfuselage, vertical tail, and wing panels delivered earlier by Rockwell subcontractors. The forward fuselage was due in Palmdale in October, with rollout of the first orbiter scheduled for the third quarter of 1976. Approach and landing tests would begin during the second quarter of 1977. (JSC Roundup; 12 Sept 75, 4)
NASA had awarded a $3:358-million contract to RCA Corp.'s AstroElectronics Div. to build a return-beam vidicon (RBV) two-camera TV system for the Landsat-C spacecraft. With twice the resolution offered by the cameras on Landsat-1 and 2-which viewed three identical ground scenes 160 km sq through separate spectral filters-the RBV camera system would produce side-by-side panchromatic pictures, each covering 80 km sq. (NASA Contract NAS 5-22-350; Raizen, GSFC Landsat Procurement Off, interview, 15 Sept 77; SBD, 21 Aug 75)
NASA announced selection of the Boeing Co. and Martin Marietta Corp. for negotiations leading to a contract for delivery of a base module for the first of NASA's Applications Explorer Missions (AEM-A), also known as the Heat Capacity Mapping Mission (HCMM). The base module would be a platform for the heat-capacity-mapping radiometer and all support instrumentation, including receivers, transmitters, power system, and attitude-control system. The contract would call for delivery of the base module within 20 mo of the award.
Planned for launch in 1978, AEM-A would gather thermal-inertia data from the earth's surface, data which should distinguish rock types, locate mineral resources, detect soil moisture, and read temperatures of vegetation cover. (NASA Release 75-253)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
