Home - Search - Browse - Alphabetic Index: 0- 1- 2- 3- 4- 5- 6- 7- 8- 9
A- B- C- D- E- F- G- H- I- J- K- L- M- N- O- P- Q- R- S- T- U- V- W- X- Y- Z
Solrad
Solrad 11
Solrad 11
Credit: US Navy
American series of satellites sponsored by the US Navy in a program to continuously monitor the Sun. SOLRAD was Satellite Techniques' first major project and NRL's first post-Vanguard satellite.

Status: Operational 1968. First Launch: 1968-03-05. Last Launch: 1976-03-15. Number: 4 . Gross mass: 170 kg (370 lb).

Conceived by the Space Science Division as a means of measuring and analyzing Solar Radiation, twelve SOLRAD satellites were successfully launched between June 1960 and March 1976. The first SOLRAD had an immediate scientific impact. Equipped with both X-ray and Lyman-alpha sensors, SOLRAD I quickly determined that radio fade-outs were caused by solar X-ray emissions. Subsequent SOLRADs also had important, although not quite so dramatic, scientific payoffs.

By 1972 the SolRad series satellite had grown from a 19 kg polished aluminum ball measuring 51 cm in diameter and with a useful lifetime of 10 months, to a 118 kg 12-sided cylinder measuring 76 cm x 58 cm and with a seven year life.

The SolRad satellite carried a classified ELINT payload, called Grab. It was kept secret for nearly 40 years, until its existence was revealed by the Director of the National Reconnaissance Organization (NRO) during NRL's 75th anniversary jubilee events.

NASA NSSDC Master Catalog Description

This NRL satellite was one of the SOLRAD series that began in 1960 to provide continuous coverage of solar radiation with a set of standard photometers. SOLRAD 9 was a spin-stabilized satellite oriented with its spin axis perpendicular to the sun-satellite line so that the 14 solar X-ray and UV photometers pointing radially outward from its equatorial belt viewed the sun with each revolution. Data were simultaneously transmitted via FM/AM telemetry and recorded in a core memory that read out its contents on command. Individual scientists and institutions were invited to receive and use the data transmitted on the 136-MHz telemetry band on the standard IRIG channels 3 through 8. For the period July 1971 to June 1973, the core memory data of SOLRAD 10 were used rather than those from SOLRAD 9. The SOLRAD 10 core memory failed June 11, 1973, and SOLRAD 9 was heavily used until February 25, 1974, when the gas supply of the attitude control system was exhausted. Lacking attitude control, SOLRAD 9 was operationally useless and was turned off. For more details, see R. W. Kreplin and D. M. Horan, "The NRL SOLRAD 9 Satellite Solar Explorer B 1968-17A," NRL Report 6800, 1969.

NASA NSSDC Master Catalog Description

SOLRAD 10, a spin-stabilized satellite, was one of the SOLRAD series designed to provide continuous coverage of wavelength and intensity changes in solar radiation in the UV, soft, and hard X-ray regions. SOLRAD 10 also mapped the celestial sphere using a high-sensitivity X-ray detector. The spacecraft was a 12-sided cylinder that measured 76 cm in diameter and 58 cm in height. Four symmetrically placed 17.8-by 53.3-cm solar cell panels, hinged at the central section of the structure, served as the elements of a turnstile antenna system. Eighteen solar sensors were mounted pointing parallel to the spin axis of the satellite, which pointed directly at the solar disk. The plane of rotation shifted about 1 deg/day so that a stellar detector mounted to point radially outward from the axis scanned the celestial sphere. Data from all detectors were stored in a 54-kbs core memory and telemetered on command to the NRL tracking station at Blossom Point, MD. Data were also transmitted in real time at 137.710 MHz. For additional information, see Naval Res. Review, v. 25, p. 1, 1971.

NASA NSSDC Master Catalog Description

The NRL SOLRAD 8 satellite was one of the SOLRAD series that began in 1960 to provide continuous coverage of solar radiation with a set of standard photometers. SOLRAD 8 was a spin-stabilized satellite oriented with its spin axis perpendicular to the sun-satellite line so that the 14 solar X-ray and ultraviolet photometers pointing radially outward from its equatorial belt viewed the sun with each revolution. Data were transmitted in real time by means of an FM/AM telemetry system and were recorded by the stations on the STADAN tracking network. The satellite performed normally except for the spin system, which failed to maintain 60 rpm (at spin rates below 10 rpm data reduction became difficult). The spin rate gradually decreased to 4 rpm on September 12, 1966. At that time, ground command succeeded in reactivating spinup to 78 rpm, which exhausted the gas supply. From this point, the spin rate gradually decreased to 10 rpm in August 1967, when data collection was substantially decreased.

More at: Solrad.
Subtopics
Solrad Model Vehicle evaluation payload built by Naval Research Laboratory (NRL) for Naval Research Laboratory (NRL) / US Navy, USA. Launched 1960.
Family: Astronomy, High earth orbit, Solar. Country: USA. Engines: Star 17A. Launch Vehicles: Titan, Titan IIIC, Scout, Scout B. Projects: Explorer. Launch Sites: Wallops Island, Cape Canaveral, Wallops Island LA3A, Cape Canaveral LC40. Agency: USN. Bibliography: 126, 2, 6, 6894, 13115, 13116.
Photo Gallery
Solrad 1Solrad 1
Credit: US Navy
Solrad 10Solrad 10
Credit: US Navy
Solrad 1Solrad 1
Credit: US Navy
LOFTI 2BLOFTI 2B
Credit: Manufacturer Image
Explorer 37Explorer 37
Credit: Manufacturer Image
SE CSE C
Credit: Manufacturer Image
Solrad 11ASolrad 11A
Credit: Manufacturer Image
Solrad ModelSolrad Model
Credit: Manufacturer Image
1968 March 5 - . 18:28 GMT - . Launch Site: Wallops Island. Launch Complex: Wallops Island LA3A. LV Family: Scout. Launch Vehicle: Scout B. FAILURE: Partial Failure.. Failed Stage: 4.
1971 July 8 - . 22:58 GMT - . Launch Site: Wallops Island. Launch Complex: Wallops Island LA3A. LV Family: Scout. Launch Vehicle: Scout B.
1976 March 15 - . 01:25 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC40. LV Family: Titan. Launch Vehicle: Titan IIIC.
Back to top of page
Home - Search - Browse - Alphabetic Index: 0- 1- 2- 3- 4- 5- 6- 7- 8- 9
A- B- C- D- E- F- G- H- I- J- K- L- M- N- O- P- Q- R- S- T- U- V- W- X- Y- Z
© 1997-2019 Mark Wade - Contact
© / Conditions for Use