ISIS (satellite)

Summary

ISIS 1 /ISIS-A
OperatorCSA / NASA
COSPAR ID1969-009A
SATCAT no.03669
Spacecraft properties
ManufacturerRCA Victor
Launch mass241.0 kilograms (531.3 lb)
Start of mission
Launch date30 January 1969, 06:43:00 (1969-01-30UTC06:43Z) UTC
RocketDelta E1 485/D65
Launch siteVandenberg SLC-2E
Orbital parameters
Reference systemGeocentric
RegimeLEO
Eccentricity0.017475
Perigee altitude578 kilometres (359 mi)
Apogee altitude3,526 kilometres (2,191 mi)
Inclination82.42º
Period128.42 minutes
 
ISIS 2 (ISIS-B)
OperatorCSA / NASA
COSPAR ID1971-024A
SATCAT no.05104
Spacecraft properties
ManufacturerRCA Victor
Launch mass264.0 kilograms (582.0 lb)
Start of mission
Launch date01 April 1971, 02:53:00 (1971-04-01UTC02:53Z) UTC
RocketDelta E1
Launch siteVandenberg SLC-2E
Orbital parameters
Reference systemGeocentric
RegimeLEO
Eccentricity0.0045
Perigee altitude1,358 kilometres (844 mi)
Apogee altitude1,458 kilometres (906 mi)
Inclination88.1º
Period113.6 minutes
 

ISIS 1 and 2 ("International Satellites for Ionospheric Studies") were the third and fourth in a series of Canadian satellites launched to study the ionosphere over one complete solar cycle. After the success of Canada's Alouette 1, Canada and the United States jointly sent up three more satellites in the ISIS program. The first was named Alouette 2 (after originally being named ISIS-X). As was the case for the Alouette satellites, RCA Ltd. of Montreal was the prime contractor for both ISIS 1 and 2.[1]

A third satellite, ISIS 3, was scheduled for construction, but when the government's focus shifted towards communications satellites, it was cancelled in 1969. The funds were instead used to produce the Communications Technology Satellite (also known as Hermes), which was launched in 1976.[2]

ISIS 1

ISIS 1 (1969-009A) was launched at 6h46 UTC[citation needed] on January 30, 1969 by a Delta rocket at the Western test range at Vandenberg AFB in California.[3]

Unlike the Alouette satellites, the ISIS had complex navigational equipment and a tape recorder to record some experiments when they were out of communications range and play back the results when the satellites came over Canada again.[1] Some other experiments were not recorded but data was sent in over several stations around the globe. In total it conducted 10 experiments.

ISIS 2

ISIS 2 (1971-024A) was launched at 2h57 UTC[citation needed] on April 1, 1971 on a Delta rocket also from the Western test range at Vandenberg AFB in California.[4] Due to budget constraints, the design of ISIS 2 was largely similar to that of ISIS I. The main difference was the addition of two experiments designed to study atmospheric optical emissions, including a photometer. This allowed images to be taken for the first time of an Aurora Borealis as seen from above.[5]

On March 13, 1984, both ISIS 1 and ISIS 2 were loaned to Japan's Communications Research Laboratory, which continued to operate the satellites until 1990, when they were shut down due to deterioration of battery capacity.[6]

See also

External links

  • ISIS program from the Canadian Space Agency
  • ISIS Satellite program
  • ISIS-I at NSSDC (1969-009A)
  • ISIS-II at NSSDC (1971-024A)

References

  1. ^ a b Agency, Canadian Space (2000-06-16). "Building on the Success of Alouette with ISIS I and II". www.asc-csa.gc.ca. Retrieved 2021-04-09.
  2. ^ "Alouette 1 – Celebrating 50 Years of Canada in Space". SpaceQ. 2012-09-06. Retrieved 2021-04-09.
  3. ^ "NASA - NSSDCA - Spacecraft - Details". NASA Space Science Data Coordinated Archive. Retrieved 2021-04-09.
  4. ^ "NASA - NSSDCA - Spacecraft - Details". NASA Space Science Data Coordinated Archive. Retrieved 2021-04-09.
  5. ^ "ISIS-II space mission launched University of Calgary's international reputation for auroral research". University of Calgary. 2021-03-29. Retrieved 2021-04-09.
  6. ^ "Alouette/ISIS: How it all Began". www.ieee.ca. Retrieved 2021-04-09.