View source for Engineering:Intelsat 901

'''Intelsat 901''' ('''IS-901''') is the first of nine new Intelsat satellites launched in June 2001 at 18° West, providing [[Astronomy:Ku band|Ku-band]] spot beam coverage for Europe and [[Astronomy:C band (IEEE)|C-band]] coverage for the [[Earth:Atlantic Ocean|Atlantic Ocean]] region. It is capable of selectable split uplink for Satellite news gathering (SNG), tailored for increased communications demands such as DTH and Internet.
{{Short description|Communications satellite}}
{{coord|0|-18|display=title}}
{{Infobox spaceflight
| name              = Intelsat 901
| names_list        = IS-901
| image             = Intelsat 901.jpg
| image_caption     = Intelsat 901 satellite seen in orbit by MEV-1
| image_size        = 300px

| mission_type      = [[Astronomy:Communications satellite|Communications]]
| operator          = [[Company:Intelsat|Intelsat]]
| COSPAR_ID         = 2001-024A
| SATCAT            = 26824
| website           = 
| mission_duration  = 13 years (planned)<br/>{{time interval|9 June 2001 23:47:50|show=ymd|sep=,}} (elapsed)

| spacecraft        = Intelsat 901
| spacecraft_type   = [[Engineering:SSL 1300|SSL 1300]]
| spacecraft_bus    = [[Engineering:SSL 1300|SSL 1300HL]]
| manufacturer      = [[Company:SSL|Space Systems/Loral]]
| launch_mass       = {{cvt|4725|kg}}
| dry_mass          = 
| dimensions        = 
| power             = 8.6 [[Watt|kW]]

| launch_date       = 9 June 2001, 06:45 [[Physics:Coordinated Universal Time|UTC]]
| launch_rocket     = Ariane 44L (VA141)
| launch_site       = [[Organization:Guiana Space Centre|Centre Spatial Guyanais]], ELA-2
| launch_contractor = [[Company:Arianespace|Arianespace]]

| entered_service   = 
| disposal_type     = 
| deactivated       = 
| last_contact      = 

| orbit_reference   = [[Astronomy:Geocentric orbit|Geocentric orbit]]
| orbit_regime      = [[Astronomy:Geostationary orbit|Geostationary orbit]]
| orbit_longitude   = Current position: 27.5° West<br/>First orbital position: 67.5° West
| apsis             = gee

| trans_band        = 56 [[Astronomy:Transponder (satellite communications)|transponders]]:<br/>44 [[Astronomy:C band (IEEE)|C-band]]<br/>12 [[Astronomy:Ku band|Ku-band]]
| trans_frequency   = 
| trans_bandwidth   = 36 and 72 [[Hertz|MHz]]
| trans_capacity    = 
| trans_coverage    = 
| trans_EIRP        = C-band global beam 36 dBW<br/>C-band Hemi Beam 38 dBW<br/>C-band beam zone 38 dBW<br/>Ku-band 53 dBW Europe Spot 1<br/>Ku-band 52 dBw Europe Spot 2
{{Infobox spaceflight/Dock
   | docking_target  = [[Engineering:Mission Extension Vehicle#Missions|MEV-1]]
   | docking_type    = dock
   | docking_date    = 25 February 2020, 07:15 UTC

   | undocking_date  =  2025  (planned)
   | time_docked     = {{time interval|25 February 2020, 07:15|show=d}} ''(in progress)''<br />~5 years(planned)
}}
| programme         = [[Company:Intelsat|Intelsat constellation]]
| previous_mission  = Intelsat 806
| next_mission      = [[Engineering:Intelsat 902|Intelsat 902]]
}}

== Satellite ==
Intelsat 901 was launched by an [[Engineering:Ariane 4|Ariane 4]] from the [[Organization:Guiana Space Centre|Centre Spatial Guyanais]] in French Guiana on 9 June 2001 at 06:45 [[Physics:Coordinated Universal Time|UTC]].<ref name=da-20010609>{{cite news|url=https://spaceref.com/press-release/arianespace-flight-141-intelsat-901-is-in-orbit/|title=ARIANESPACE FLIGHT 141 – Intelsat 901 is in orbit!|website=spaceref.com|date=9 June 2001|access-date=5 March 2023}}</ref><ref name="EA-A44L">{{cite web |url=http://www.astronautix.com/lvs/arine44l.htm|title=Ariane 44L|publisher=Encyclopedia Astronautica|url-status=dead|archive-url=https://web.archive.org/web/20150302201545/http://www.astronautix.com/lvs/arine44l.htm|archive-date=2 March 2015}}</ref>

* '''Increased power''' – Intelsat 901 is designed to provide up to 5 [[Physics:Decibel|dB]] for downlink EIRP, and up to 1.8 dB for G/T over the Intelsat 7 series satellites.
* '''Increased Capacity''' – with over 72 C-band, 36 [[Hertz|MHz]] equivalent unit [[Astronomy:Transponder (satellite communications)|transponders]], Intelsat 901 provides a significant increase in capacity over the previous satellite at 18° West.
* '''Improved Coverage''' – Intelsat 901 provides significantly expanded zone coverage. The Ku-band spot beams also include more areas within each zone.

== Encounter with Russian Olymp-K satellite ==
On 9 October 2015, SpaceNews reported that in April 2015, the {{wipe|Russia}} satellite ''Olymp-K'' had moved to within {{cvt|10|km}} of Intelsat 901 and the nearby [[Company:Intelsat|Intelsat 7]], causing concerns of a safety-of-flight incident. Attempts by Intelsat to contact the Russian satellite operators were unsuccessful and no reason for the satellite's movement was given by the Russian government. The move sparked classified meetings within the Department of Defense and heightened suspicions that Olymp-K satellite was performing [[Signals intelligence|signals intelligence]], or was possibly an [[Engineering:Anti-satellite weapon|anti-satellite weapon]].<ref>{{cite web|last1=Gruss|first1=Mike|url=https://spacenews.com/russian-satellite-maneuvers-silence-worry-intelsat/|title=Russian Satellite Maneuvers, Silence Worry Intelsat|publisher=SpaceNews|date=9 October 2015|access-date=30 March 2021}}</ref>

== Mission Extension Vehicle-1 (MEV-1) ==
On 9 October 2019, [[Engineering:Mission Extension Vehicle|Mission Extension Vehicle]]-1 (MEV-1) launched from Baikonur Cosmodrome in Kazakhstan on a [[Engineering:Proton-M|Proton-M]] [[Engineering:Launch vehicle|launch vehicle]]. Its mission is to dock with Intelsat 901 and extend its operational lifespan by performing [[Astronomy:Orbital station-keeping|station-keeping]] for the aging satellite.<ref>{{cite web|url=https://www.northropgrumman.com/Capabilities/SpaceLogistics/Pages/default.aspx |title=Space Logistics Services|publisher=Northrop Grumman|access-date=18 October 2019}}</ref> Before the docking of MEV-1 and Intelsat 901, ground controllers transitioned customers off of Intelsat 901 and moved the satellite to a [[Astronomy:Graveyard orbit|graveyard orbit]] in December 2019 so that [[Company:Intelsat|Intelsat 37e]] could use its orbital slot.

Docking occurred on 25 February 2020 at 07:15 UTC. MEV-1 rendezvoused with Intelsat 901, reached out with mechanical fingers, and grabbed the target craft using its liquid propellant engine as a grapple point to pull the two satellites together.<ref>{{cite web|last=Clark|first=Stephen|url=https://spaceflightnow.com/2020/02/26/two-commercial-satellites-link-up-in-space-for-first-time/|title=Two commercial satellites link up in space for first time|publisher=Spaceflight Now|date=26 February 2020|access-date=17 April 2020}}</ref> Over the next two months, [[Company:Northrop Grumman|Northrop Grumman]] and satellite prime contractor [[Company:SSL|Space Systems/Loral]] performed tests on the satellites' systems before using MEV-1 to lower Intelsat 901 back to the geosynchronous arc at 27.5° West (332.5° East) orbital longitude, where it will remain for five years.<ref>{{cite web|last=Chang|first=Kenneth|url=https://www.nytimes.com/2020/02/26/science/mev-1-northrop-grumman-space-junk.html|title=A Meeting in Orbit Demonstrates a Space Junk Solution |newspaper=The New York Times|date=26 February 2020|access-date=17 April 2020}}</ref>

On 17 April 2020, Intelsat and Northrop Grumman announced that Intelsat 901 had officially returned to operational service on 2 April 2020 at its new orbital longitude. The satellite replaces [[Engineering:Intelsat 907|Intelsat 907]], a 17-year-old satellite now four years past its design life. After five years, MEV-1 will move Intelsat 901 back to a final graveyard orbit and release it before moving to another potential client.<ref>{{cite press release|url=https://news.northropgrumman.com/news/releases/intelsat-901-satellite-returns-to-service-using-northrop-grummans-mission-extension-vehicle|title=Intelsat 901 Satellite Returns to Service Using Northrop Grumman's Mission Extension Vehicle|publisher=Northrop Grumman|date=17 April 2020|access-date=17 April 2020}}</ref><ref>{{Cite web|url=https://spacenews.com/intelsat-901-satellite-with-mev-1-servicer-attached-resumes-service/|title=Intelsat-901 satellite, with MEV-1 servicer attached, resumes service|date=17 April 2020}}</ref>

== Ku-band specifications ==
* Total transponders: Ku-Band up to 22 (in equivalent 36 MHz units)
* Polarization: Ku-Band Linear - Horizontal or Vertical
* Uplink frequency: Ku-Band 14.00 to 14.50 GHz
* Downlink frequency: Ku-Band 10.95 to 11.20 GHz and 11.45 to 11.70 GHz
* G/T (Ku-Band) (Beam Peak): Spot 1: up to +9.0 dB/K,  Spot 2: up to +9.0 dB/K
* SFD Range (Beam Edge): Ku-Band -87.0 to -69.0 dBW/m<sup>2</sup>

== References ==
{{Reflist|30em}}

== External links ==
* [http://www.intelsat.com/fleetmaps/?s=IS-901-330 Intelsat 901]

{{Intelsat}}

[[Category:Intelsat satellites]]

{{Sourceattribution|Intelsat 901}}