Ariel 6
UK-6 before launch
Mission typeAstronomy
COSPAR ID1979-047A Edit this at Wikidata
SATCAT no.11382
Mission duration2.5 years
Spacecraft properties
ManufacturerMarconi Company (UK)
Launch mass154.5 kilograms (341 lb)
Start of mission
Launch date2 June 1979, 23:26:00 (1979-06-02UTC23:26Z) UTC
RocketScout D-1 (SN S198C)
Launch siteWallops Flight Center, LA-3A
End of mission
DeactivatedFebruary 1982 (1982-03)
Decay date23 September 1990
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Perigee altitude605 kilometres (376 mi)
Apogee altitude651 kilometres (405 mi)
Period97.3 minutes
Epoch1 July 1979[1]
← Ariel 5

Ariel 6, known pre-launch as UK-6, was a British and American satellite launched in 1979 as part of the Ariel programme. It was operated by the Science Research Council, which became the Science and Engineering Research Council in 1981. Ariel 6 was used for astronomical research and provided data until February 1982. It was the last Ariel satellite to be launched.[2]

Satellite design


The spacecraft was manufactured by the Marconi Company,[3] and had a mass of 154.5 kilograms (341 lb).[2]


The primary experiment, the cosmic ray detector, could sense heavy cosmic rays with an atomic number over 30. The 480-millimetre (19 in) diameter acrylic-lined aluminum sphere was filled with a gaseous oxygen, nitrogen, and helium mixture. Heavy cosmic rays penetrated the sphere and excited the gas to produce scintillation light; the acrylic produced Cerenkov radiation. These ultraviolet emissions were detected with 16 photo-multipliers. Data processing to separate the two different types of ultraviolet emissions was performed by comparing the brightness and duration of the emissions. The amplitude of the signal was used to determine the atomic number of the cosmic ray. Unlike the X-ray experiments, this experiment had no pointing requirements other than what was required for thermal control.[4]

The two other experiments were X-ray telescopes.[5] One detected low-energy X-rays and the other high-energy X-rays.[4]



A Scout D-1 carrier rocket (SN S198C) was used to launch Ariel 6 from Launch Area 3A at the Wallops Flight Center. The launch was successfully conducted at 23:26:00 UTC on 2 June 1979.[6][7] Once the satellite achieved orbit it was renamed from UK-6 to Ariel 6.[8]


Ariel 6 operated in a 599 by 653 kilometres (372 by 406 mi) low Earth orbit, at an inclination of 55.0° and with an orbital period of 97.22 minutes as of 15 July 1979.[1] The satellite provided data until February 1982.[9] It decayed from orbit and reentered the atmosphere on 23 September 1990.[1]


Interference from radar signals prevented the satellite from pointing correctly, and affected the data that it returned.[9]


  1. ^ a b c "Ariel 6 Launch Information". NASA Space Science Data Coordinated Archive. Retrieved 4 June 2010.
  2. ^ a b "Ariel 6 Spacecraft Details". NASA Space Science Data Coordinated Archive. Retrieved 4 June 2010.
  3. ^ "Wallops to Launch British Satellite". The Daily Times. Salisbury, Maryland. 20 May 1979. p. A7 – via
  4. ^ a b Dalziel 1979, p. 417.
  5. ^ Pounds, Kenneth A. (1981). "The European Programme in X-Ray Astronomy". Journal of the Washington Academy of Sciences. 71 (2): 104–114. ISSN 0043-0439. JSTOR 24537242.
  6. ^ Krebs, Gunter. "Ariel 6 (UK 6)". Gunter's Space Page. Retrieved 4 June 2010.
  7. ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Archived from the original on 7 May 2010. Retrieved 3 June 2010.
  8. ^ Dalziel 1979, p. 413.
  9. ^ a b "The Ariel VI Satellite". HEASARC. NASA. Retrieved 4 June 2010.