Iridium 33
{{short description|Communications satellite operated by Iridium Communications}}
{{Infobox spaceflight
| name = Iridium 33
| image = Iridium satellite.jpg
| image_caption = A mockup of an Iridium satellite
| mission_type = Communication
| operator = Iridium Satellite LLC
| website =
| COSPAR_ID = 1997-051C
| SATCAT = 24946
| mission_duration = {{time interval|September 14, 1997 01:36|February 10, 2009 16:56|show=y}}
| spacecraft_bus = LM-700A
| manufacturer = Lockheed Martin
| dry_mass =
| launch_mass = 700 kg
| power =
| launch_date = 14 September 1997, 01:36 UTC
| launch_rocket = Proton-K / DM2
| launch_site = Baikonur, Site 81/23
| launch_contractor = Khrunichev
via International Launch Services
| entered_service =
| destroyed = 10 February 2009, 16:56 UTC
{{nowrap|Collision with Kosmos 2251}}
| orbit_epoch = 10 February 2009
| orbit_reference = Geocentric
| orbit_regime = Low Earth
| orbit_periapsis = 779.6 km {{cite web|url=https://www.n2yo.com/satellite/?s=24946|title=Iridium 33 tracking details|access-date=2019-02-04}}
| orbit_apoapsis = 799.9 km
| orbit_inclination = 86.4°
| orbit_period = 100.4 minutes
| apsis = gee
}}
Iridium 33 was a communications satellite launched by Russia for Iridium Communications. It was launched into low Earth orbit from Site 81/23 at the Baikonur Cosmodrome at 01:36 UTC on 14 September 1997, by a Proton-K rocket with a Block DM2 upper stage.{{cite web|url=http://www.astronautix.com/project/iridium.htm |title=Iridium|last=Wade|first=Mark|publisher=Encyclopedia Astronautica|access-date=2009-02-12|url-status=dead |archive-url=https://web.archive.org/web/20090216185343/http://www.astronautix.com/project/iridium.htm |archive-date=2009-02-16}}{{cite web|url=http://www.astronautix.com/lvs/proton.htm|archive-url=https://web.archive.org/web/20080913224630/http://www.astronautix.com/lvs/proton.htm|url-status=dead|archive-date=September 13, 2008|title=Proton |last=Wade|first=Mark|publisher=Encyclopedia Astronautica|access-date=2009-02-12}} The launch was arranged by International Launch Services (ILS). It was operated in Plane 3 of the Iridium satellite constellation, with an ascending node of 230.9°.
Mission
Iridium 33 was part of a commercial communications network consisting of a constellation of 66 LEO spacecraft. The system uses L-Band to provide global communications services through portable handsets. Commercial service began in 1998. The system employs ground stations with a master control complex in Landsdowne, Virginia, a backup in Italy, and a third engineering center in Chandler, Arizona.
Spacecraft
The spacecraft was 3-axis stabilized, with a hydrazine propulsion system. It had 2 solar panels with 1-axis articulation. The system employed L-Band using FDMA/TDMA to provide voice at 4.8 kbps and data at 2400 bps with a 16 dB margin. Each satellite had 48 spot beams for Earth coverage and used Ka-Band for crosslinks and ground commanding.{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1997-051C|title=Iridium 33: Display 1997|website=nssdc.gsfc.nasa.gov|publisher=NASA|date=14 May 2020|access-date=5 June 2020}} {{PD-notice}}
Destruction
{{main|2009 satellite collision}}
On 10 February 2009, at 16:56 UTC, at about 800 km altitude, Kosmos 2251 (1993-036A) (a derelict Strela satellite) and Iridium 33 collided, resulting in the destruction of both spacecraft.{{cite web|url=http://www.space.com/news/090211-satellite-collision.html|title=U.S. Satellite Destroyed in Space Collision|last=Iannotta|first=Becky|date=2009-02-11|publisher=Space.com|access-date=2009-02-11}} NASA reported that a large amount of space debris was produced by the collision, i.e. 1347 debris for Kosmos 2251 and 528 for Iridium 33.{{cite web|url=https://www.google.com/hostednews/ap/article/ALeqM5grGfFhzFgjxK46MQHTwD1RgRUwCAD969LB802|archive-url=https://web.archive.org/web/20090216044137/http://www.google.com/hostednews/ap/article/ALeqM5grGfFhzFgjxK46MQHTwD1RgRUwCAD969LB802|url-status=dead|archive-date=February 16, 2009|title=2 orbiting satellites collide 500 miles up|date=2009-02-11 |publisher=Associated Press|access-date=2009-02-11}}{{cite web|url=http://www.john.geek.nz/2009/03/satellite-collision-google-earth-kmz-file/|title=Google Earth KMZ file of the debris|date=2009-03-05|publisher=John Burns|access-date=2010-11-25}}{{cite web|url=http://www.oosa.unvienna.org/pdf/pres/stsc2011/tech-31.pdf|title=U.S. Space debris environment and operational updates|date=2011-02-18 |publisher=NASA|access-date=5 June 2020}} {{PD-notice}}{{cite web|title=Javascript visualisation of Iridium 33 debris|url=http://stuffin.space/?search=1997-051}}
See also
References
{{reflist}}
{{Portal|Spaceflight}}
{{wikinews|has=news coverage of the 2009 satellite collision|Russian and US satellites collide|Burning debris from satellites spotted over several US cities}}
{{Orbital launches in 1997}}
{{authority control}}
Category:Communications satellites in low Earth orbit
Category:Satellites formerly orbiting Earth