ISIS (satellite)
Encyclopedia
ISIS I and II were the third and fourth satellites that were launched in a series of Canadian
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 satellite
Satellite
In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....

s sent up to study the ionosphere
Ionosphere
The ionosphere is a part of the upper atmosphere, comprising portions of the mesosphere, thermosphere and exosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere...

. After the success of Canada's Alouette 1
Alouette 1
Alouette 1 was Canada's first satellite, and the first satellite constructed by a country other than the USSR or the United States. Occasionally, Alouette 1 is misrepresented as the third satellite successfully put in orbit, rather than being from the third country to have one of its own in space,...

, Canada and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 decided to jointly launch three more satellites which they called the ISIS program. The first of the three was named Alouette 2
Alouette 2
Alouette 2 was a Canadian research satellite launched at 04:48 UTC on November 29, 1965 by a Thor Agena rocket with Explorer 31 from the Western test range at Vandenberg AFB in California...

 (after originally being named ISIS-X). As was the case for the Alouette satellites, RCA Victor of Montreal
Montreal
Montreal is a city in Canada. It is the largest city in the province of Quebec, the second-largest city in Canada and the seventh largest in North America...

 was the prime contractor for both ISIS I and II.

There was a final satellite scheduled for construction, but when the government's focus shifted towards communications satellites, it was cancelled in 1969.

ISIS I

ISIS I was launched at 6h46 UTC on January 30, 1969 by a Delta rocket
Delta rocket
Delta is a versatile family of expendable launch systems that has provided space launch capability in the United States since 1960. There have been more than 300 Delta rockets launched, with a 95 percent success rate. Two Delta launch systems – Delta II and Delta IV – are in active use...

 at the Western test range at Vandenberg AFB in California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

. Canada stopped using ISIS I on March 13, 1984 but Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 was authorized to keep on using it and did so until 1990.

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. Some other experiments were not recorded but data was sent in over several stations around the globe. In total it conducted 10 experiments.

ISIS II

ISIS II was launched at 2h57 UTC on April 1, 1971 on a Delta rocket
Delta rocket
Delta is a versatile family of expendable launch systems that has provided space launch capability in the United States since 1960. There have been more than 300 Delta rockets launched, with a 95 percent success rate. Two Delta launch systems – Delta II and Delta IV – are in active use...

 also from the Western test range at Vandenberg AFB in California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

. Due to budget constraints, the design of ISIS II was largely similar to that of ISIS I. The main difference was the addition of two experiments designed to study atmospheric optical emissions. This allowed images to be taken for the first time of an entire Aurora Borealis
Aurora (astronomy)
An aurora is a natural light display in the sky particularly in the high latitude regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere...

as seen from above.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK