View source for Ariel 3

{{for|the moped|Ariel 3 (moped)}}
{{Infobox spaceflight
| name               = Ariel 3
| names_list         = Ariel3, S 53, UK 3, UK-E
| image              = File:Ariel 3 on display pre-launch.jpg
| image_caption      = Ariel 3 with its paddles in the deployed position
| mission_type       = Atmospheric studies
| operator           = [[Science Research Council|SERC]] / [[NASA]]
| website            = 
| COSPAR_ID          = 1967-042A
| SATCAT             = 2773<ref name=nssdc />
| mission_duration   = 43 months
| spacecraft_bus     = 
| manufacturer       = 
| dry_mass           = 
| launch_mass        = {{convert|197|lb|order=flip}}
| power              = <!-- [[watt]]s -->
| launch_date        = {{start-date|5 May 1967, 16:00:01|timezone=yes}}&nbsp;UTC
| launch_rocket      = [[Scout A]]
| launch_site        = [[Vandenberg Air Force Base|Vandenberg]] [[Vandenberg AFB Space Launch Complex 5|SLC-5]]
| launch_contractor  = 
| disposal_type      = Decommissioned
| deactivated        = {{end-date|September 1969}}
| decay_date         = 14 December 1970
| orbit_epoch        = 7 June 1967<ref name="satcat">{{cite web|url=http://planet4589.org/space/log/satcat.txt|title=Satellite Catalog|first=Jonathan|last=McDowell|work=Jonathan's Space Page|access-date=6 December 2013}}</ref>
| orbit_reference    = [[geocentric orbit|Geocentric]]
| orbit_regime       = [[Low Earth orbit|Low Earth]]
| orbit_periapsis    = {{convert|496|km|mi}}
| orbit_apoapsis     = {{convert|599|km|mi}}
| orbit_inclination  = 80.17&nbsp;degrees
| orbit_period       = 95.69&nbsp;minutes
| orbit_eccentricity = 0.008
| apsis              = gee
| programme          = [[Ariel programme|Ariel]]
| previous_mission   = [[Ariel 2]]
| next_mission       = [[Ariel 4]]
}}

'''Ariel 3''' ('''UK 3''' or '''United Kingdom Research Satellite 3''') was a satellite in the [[Ariel programme]],  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]] 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]] designed and constructed in the [[United Kingdom]].

==Design==
===Development===
In 1961 the UK [[Space Research Group]] accepted proposals for experiments to be carried on the third satellite of the [[Ariel programme]]. The [[British National Committee for Space Research]] 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.{{sfn|Ladd|Smith|1969|p=480}} A total of 5 craft were constructed.<ref name=campbell /> One prototype, two engineering models, the final satellite and a flight spare.<ref name=campbell>{{cite journal |last1=Campbell |first1=F. P.|date=December 1966 |title=Orbiting A High Atmosphere Experiment |journal=Weather |volume=21 |issue=12 |pages=422–428 |doi=10.1002/j.1477-8696.1966.tb02797.x |bibcode=1966Wthr...21..422C}}</ref> The flight spare was later used as the basis of Ariel 4.{{sfn|Dalziel|1975|p=163}}

===Operation===
[[File:Ariel 3 satellite nickel-cadmium battery pack - Science Museum, London.jpg|thumb|Ariel 3 type nickel-cadmium battery pack]]
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.{{sfn|Sketch|1969|pp=493–494}}

The spacecraft weighed {{convert|197|lb|order=flip}}.{{sfn|Ladd|Smith|1969|p=479}}

===Sensors===
Ariel 3 carried five experiments.{{sfn|Ladd|Smith|1969|p=481}} The experiments measured properties of the [[thermosphere]] as well as detected "terrestrial radio noise" from thunderstorms and measured large-scale galactic [[radio frequency]] noise.{{sfn|Ladd|Smith|1969|p=481}} Ariel 3 was also fitted with a series of mirrors to observe the spin of the satellite.{{sfn|Dalziel|1979|p=414}}

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.{{sfn|Ladd|Smith|1969|p=485}}

Three experiments expanded on data from the previous two missions. Two experiments collected data on naturally occurring radio noise.{{sfn|Ladd|Smith|1969|p=481}}

==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.{{sfn|Ladd|Smith|1969|pp=482–483}}

It was launched from [[Vandenberg Air Force Base]] on 5 May 1967 aboard a [[Scout (rocket)|Scout]] rocket.<ref>{{cite web |url=http://news.bbc.co.uk/onthisday/hi/dates/stories/may/5/newsid_2511000/2511263.stm |title='On This Day' for May 5, 1967 - First all-British satellite 'Ariel 3' launched |work=[[BBC News]] |date=May 5, 1967 | access-date=1 January 2010}}</ref><ref name=nssdc>{{cite web |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1967-042A |website=NASA Space Science Data Coordinated Archive |title=Ariel 3 |access-date=24 March 2020 |df=dmy-all }}</ref> This made it the first artificial [[satellite]] designed and constructed in the [[United Kingdom]].{{sfn|Ladd|Smith|1969|p=479}}

===Operations===
Ariel 3 had an orbital period of approximately 95 minutes, with an [[apogee]] of 608&nbsp;km and a [[perigee]] of 497&nbsp;km. It initially spun at 31 rpm for stability, though by the time the Ariel 3 [[orbit|deorbited]], it had slowed to a rate of about 1 rpm.<ref name=nssdc/>

On 24 October 1967 the tape recorder aboard Ariel 3 began to malfunction. This restricted observation to real-time operation only.<ref name=nssdc/> Nevertheless, as of May 5, 1968, after one year in orbit, the satellite's five experiments were still functioning and had returned 400 million bits of usable data on the upper atmosphere.<ref name=aanda1968>{{cite web|title=Aeronautics and Astronautics, 1968|url=https://history.nasa.gov/AAchronologies/1968.pdf|access-date=28 April 2023|publisher=NASA|page=105}}</ref> 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.<ref name=nssdc/>

== See also ==
{{Portal|Spaceflight}}

==Notes==
{{Reflist}}

==References==
*{{cite conference|conference=Automatic Control in Space: 8th IFAC Symposium|isbn=9781483158976|date=2-6 July 1979|location=Oxford, England|last1=Dalziel|first1=R.|title=The Significance of UK Spacecraft Control to Space Science|url=https://books.google.com/books?id=shajBQAAQBAJ}}
*{{cite journal|title=An Introduction to the Ariel III Satellite Project|last1=Ladd|first1=A.C.|last2=Smith|first2=J.F.|location=Great Britain|date=August 12, 1969|volume=311|journal=Proceedings of the Royal Society of London|issue=1507|pages=479–487|doi=10.1098/rspa.1969.0129|jstor=2416326|bibcode=1969RSPSA.311..479L|s2cid=129064735}}
*{{cite journal| issn = 0080-4630| volume = 311| issue = 1507| pages = 489–499| last = Sketch| first = H. J. H.| title = Description of the Ariel III Satellite Project| journal = Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences| date = 1969| doi = 10.1098/rspa.1969.0130| jstor = 2416327| bibcode = 1969RSPSA.311..489S| s2cid = 140671893}}
*{{Cite journal| issn = 0080-4630| volume = 343| issue = 1633| pages = 161–165| last = Dalziel| first = R.| title = The Ariel 4 Satellite| journal = Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences| date = 1975| doi = 10.1098/rspa.1975.0057| jstor = 78859| bibcode = 1975RSPSA.343..161D| s2cid = 202574658}}
==External links==
* [http://www.chilton-computing.org.uk/acl/jpgs/aerial3.jpg Photograph that depicts Ariel 3]
* [http://news.bbc.co.uk/onthisday/hi/dates/stories/may/5/newsid_2511000/2511263.stm ''On This Day'' for May 5, 1967] [[BBC News]]
* [https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19670014008.pdf NASA release 67-96]
* [http://www.chilton-computing.org.uk/acl/applications/satellite/p003.htm Chilton Computing]

{{Ariel programme}}
{{Orbital launches in 1967}}

{{Use British English|date=January 2014}}
{{Use dmy dates|date=January 2014}}

[[Category:Spacecraft launched in 1967]]
[[Category:Satellites formerly orbiting Earth]]
[[Category:Space programme of the United Kingdom]]