Ariel 3 (UK 3 or United Kingdom Research Satellite 3) was a satellite in the

Ariel programme Ariel was a British satellite research programme conducted between the early 1960s and 1980s. Six satellites were launched as part of the programme, starting with the first British satellite, Ariel 1, which was launched on 26 April 1962, and concl ...

, a satellite partnership between the US and UK. Three of the onboard experiments continued research from the first two missions and two experiments were designed for new research topics. It was launched from

Vandenberg Air Force Base Vandenberg may refer to: * Vandenberg (surname), including a list of people with the name * USNS ''General Hoyt S. Vandenberg'' (T-AGM-10), transport ship in the United States Navy, sank as an artificial reef in Key West, Florida * Vandenberg Sp ...

on 5 May 1967, making it the first satellite of the program to launch from the West coast. Ariel 3 was shut down in September 1969, and re-entered the Earth's atmosphere 14 December 1970. This was the first artificial

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioi ...

designed and constructed in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

Design

Development

In 1961 the UK Space Research Group accepted proposals for experiments to be carried on the third satellite of the

. The

British National Committee for Space Research The British National Committee for Space Research (BNCSR) was a Royal Society committee formed in December 1958. It was formed primarily to be Britain's interface with the newly formed Committee on Space Research (COSPAR). History In October ...

selected experiments from those proposals and submitted them to NASA in 1962. The scientific objectives for the mission were selected in January 1963, and full work on the satellite began in early 1964 due to organisational and financial difficulties. A total of 5 craft were constructed. One prototype, two engineering models, the final satellite and a flight spare. The flight spare was later used as the basis of Ariel 4.

Operation

Power could be drawn from the batteries or the solar panels. The batteries were considered the least reliable component in the system so this method was devised to mitigate the issue. The spacecraft weighed .

Sensors

Ariel 3 carried five experiments. The experiments measured properties of the

thermosphere The thermosphere is the layer in the Earth's atmosphere directly above the mesosphere and below the exosphere. Within this layer of the atmosphere, ultraviolet radiation causes photoionization/photodissociation of molecules, creating ions; the ...

as well as detected "terrestrial radio noise" from thunderstorms and measured large-scale galactic

radio frequency Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the ...

noise. Ariel 3 was also fitted with a series of mirrors to observe the spin of the satellite. High-speed data was transmitted continuously to the Satellite Tracking and Data Acquisition Network (STADAN). Low-speed data was recorded on tape recorders and was transmitted to ground stations in the high-speed mode when commanded. Three experiments expanded on data from the previous two missions. Two experiments collected data on naturally occurring radio noise.

Mission

Launch

The launch was originally planned for Wallops; Ariel 1 and Ariel 2 had both launched on the East coast. In 1964 experimenters requested a change to the proposed orbit, from an inclination of 50–70° to 78–80° to maximize coverage at the geomagnetic latitude. This change precipitated the launch site moving to the West coast. It was launched from

on 5 May 1967 aboard a Scout rocket. This made it the first artificial

designed and constructed in the

Operations

Ariel 3 had an orbital period of approximately 95 minutes, with an

apogee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion. General description There are two apsides in any ell ...

of 608 km and a

perigee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. For example, the apsides of the Earth are called the aphelion and perihelion. General description There are two apsides in any ell ...

of 497 km. It initially spun at 31 rpm for stability, though by the time the Ariel 3 deorbited, it had slowed to a rate of about 1 rpm. On 24 October 1967 the tape recorder aboard Ariel 3 began to malfunction. This restricted observation to real-time operation only. Ariel 3 suffered from a significant power failure in December 1968, restricting the satellite's operation to daylight hours only. The satellite was completely shut down in September 1969. Its orbit decayed steadily until on 14 December 1970 when Ariel 3 re-entered Earth's atmosphere.

Notes

References

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External links

Photograph that depicts Ariel 3

''On This Day'' for May 5, 1967''

BBC News BBC News is an operational business division of the British Broadcasting Corporation (BBC) responsible for the gathering and broadcasting of news and current affairs in the UK and around the world. The department is the world's largest broad ...

NASA release 67-96

{{Use dmy dates, date=January 2014 Spacecraft launched in 1967 Satellites formerly orbiting Earth Space programme of the United Kingdom