Ariel 4

Summary

Ariel 4
Ariel-4.jpg
Ariel 4.
Mission typeIonospheric
OperatorSERC / NASA
COSPAR ID1971-109A
SATCAT no.5675
Mission duration1 year (design life)[1]
Spacecraft properties
ManufacturerBAC
Launch mass99.5 kilograms (219 lb)
Start of mission
Launch date11 December 1971, 20:47:01 (1971-12-11UTC20:47:01Z) UTC
RocketScout B-1-F S183C
Launch siteVandenberg SLC-5
ContractorNASA
End of mission
Decay date12 December 1978
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Eccentricity0.00795
Perigee altitude473 kilometres (294 mi)
Apogee altitude590 kilometres (370 mi)
Inclination82.9 degrees
Period95.26 minutes
Epoch10 January 1972[2]
← Ariel 3
Ariel 5 →
 

Ariel 4, known pre-launch as UK 4, was a British ionospheric research satellite, which was operated by the Science and Engineering Research Council. It was launched 11 December 1971, aboard an American Scout rocket. Experiments were designed to meet one scientific objective, making it the first mission-oriented satellite for the UK. It was also the first satellite in the Ariel programme to contain an American experiment. Ariel 4 decayed from orbit on 12 December 1978

Design

Development

Ariel 4 leveraged both the design and hardware of Ariel 3 to reduce costs. Ariel 4 used pieces of its predecessor's flight backup unit and spare parts. The satellite cost about 1.25 million pounds.[3]

Operation

British Aircraft Corporation was the prime contractor.[4] Ariel 4 had a launch mass of 101 kilograms (223 lb).[3] It was the first satellite in the Ariel programme to be able to perform attitude maneuvers.[5]

Sensors

It was the first satellite of the Ariel programme to have a mission-orientated payload, where all of the experiments are designed to research one scientific objective. The scientific objective was to "...study the interaction between high energy charged particles and electromagnetic radiation in the upper ionsphere and magnetosphere.[6] Three of the five experiments on Ariel 3 were to determine a single scientific objective, so those three were improved for use on Ariel 4 and an additional experiment was added.[7]

Experiments accounted for 18.5 kilograms (41 lb) of the spacecraft's mass.[3]

It was also the first in the program to carry an American experiment.[6]

Mission

Launch

The launch of Ariel 4 occurred at 20:47:01 GMT on 11 December 1971, from Space Launch Complex 5 at the Vandenberg Air Force Base.[1] It was conducted by NASA, using a Scout B-1 rocket.[8]

Operations

Ariel 4 was placed into a low Earth orbit, with a perigee of 473 kilometres (294 mi), an apogee of 590 kilometres (370 mi), 82.9 degrees of inclination and an orbital period of 95.3 minutes as of 10 January 1972. It decayed from orbit on 12 December 1978.[2]

See also

Notes

  1. ^ a b "Ariel 4 General Information". NASA Space Science Data Coordinated Archive. Retrieved 24 March 2020.
  2. ^ a b McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 6 December 2013.
  3. ^ a b c Dalziel 1975, p. 163.
  4. ^ Dalziel 1975, p. 165.
  5. ^ Dalziel 1979, p. 413.
  6. ^ a b Dalziel 1975, p. 161.
  7. ^ Dalziel 1975, p. 162.
  8. ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 8 September 2009.

References

  • Dalziel, R. (1975). "The Ariel 4 Satellite". Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences. 343 (1633): 161–165. Bibcode:1975RSPSA.343..161D. doi:10.1098/rspa.1975.0057. ISSN 0080-4630. JSTOR 78859.CS1 maint: ref=harv (link)
  • Dalziel, R. (2–6 July 1979). The Significance of UK Spacecraft Control to Space Science. Automatic Control in Space: 8th IFAC Symposium. Oxford, England. ISBN 9781483158976.CS1 maint: ref=harv (link)