Sirius was a constellation of

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Rad ...

s operated at 5.0° East in

geostationary orbit A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular orbit, circular geosynchronous or ...

(GEO) by

NSAB In Mandaeism, Nṣab () is an uthra (angel or guardian). He is also called Nṣab Rba ("the Great Nṣab") or Nṣab Ziwa ("the Radiant Nṣab" or "Splendid Plant"). Nṣab and Anan-Nṣab ('cloud of Nṣab', a female consort) are frequently me ...

(later

SES Sirius SES Sirius, formerly called Nordic Satellite AB (NSAB) was the owner and operator of the two Sirius satellites, which provide the Nordic countries and the Baltic states, with TV, radio, data and communications solutions. The company is today entirel ...

, and now a non-autonomous part of

SES SES, S.E.S., Ses and similar variants can refere to: Business and economics * Socioeconomic status * Scottish Economic Society, a learned society in Scotland * SES, callsign of the TV station SES/RTS (Mount Gambier, South Australia) * SES, a ...

, owner and operator of the

Astra satellites Astra (Latin for "stars") may refer to: People * Astra (name) Places * Astra, Chubut, a village in Argentina * Astra (Isauria), a town of ancient Isauria, now in Turkey * Astra, one suggested name for a hypothetical fifth planet (hypothetical), ...

). They carried

digital Digital usually refers to something using discrete digits, often binary digits. Businesses *Digital bank, a form of financial institution *Digital Equipment Corporation (DEC) or Digital, a computer company *Digital Research (DR or DRI), a software ...

satellite television Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location.ITU Radio Regulations, Section IV. Radio Stations and Systems ...

to the countries of

Scandinavia Scandinavia is a subregion#Europe, subregion of northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. ''Scandinavia'' most commonly refers to Denmark, Norway, and Sweden. It can sometimes also ...

Baltic states The Baltic states or the Baltic countries is a geopolitical term encompassing Estonia, Latvia, and Lithuania. All three countries are members of NATO, the European Union, the Eurozone, and the OECD. The three sovereign states on the eastern co ...

Eastern Europe Eastern Europe is a subregion of the Europe, European continent. As a largely ambiguous term, it has a wide range of geopolitical, geographical, ethnic, cultural and socio-economic connotations. Its eastern boundary is marked by the Ural Mountain ...

and

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

, including the

Viasat Viasat may refer to: *Viasat (American company) (founded 1986) ** Viasat hack, a cyberattack on the Viasat KA-SAT network that happened in February 2022 *Viasat (Nordic television service) Viasat is a direct broadcast satellite, satellite and pa ...

pay TV Pay television, also known as subscription television, premium television or, when referring to an individual service, a premium channel, refers to subscription-based television services, usually provided by multichannel television providers, b ...

system, along with several pay TV packages for Eastern Europe, the

TopTV StarSat (formerly TopTV until 31 October 2013) was a South African direct broadcast satellite television service that began broadcasting on 1 May 2010. StarSat was operated by On Digital Media, who were granted a pay-TV license by ICASA in Septe ...

package for Africa, a number of Ukrainian channels and the national Latvian and

Lithuanian Lithuanian may refer to: * Something of, from, or related to Lithuania, a country in the Baltic region in northern Europe ** Lithuanian language ** Lithuanians, a Baltic ethnic group, native to Lithuania and the immediate geographical region ** L ...

channel service

free-to-air Free-to-air (FTA) services are television (TV) and radio services broadcast in unencrypted form, allowing any person with the appropriate receiving equipment to receive the signal and view or listen to the content without requiring a subscri ...

Satellites

Sirius 4

A fourth satellite, Sirius 4, was ordered in 2005 and launched at 22:39:47 UTC on 17 November 2007. It carries 52 active

Ku-band The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally ), because it is the lower part of the original NATO K band ...

transponder In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight trans ...

s and two active

Ka-band The Ka band (pronounced as either "kay-ay band" or "ka band") is a portion of the microwave part of the electromagnetic spectrum. The designation "Ka-band" is from Kurz-above, which stems from the German word ''kurz,'' meaning "short". There ...

transponders. Sirius 4 was built by

Lockheed Martin Space Systems Lockheed Martin Space is one of the four major business divisions of Lockheed Martin. It has its headquarters in Littleton, Colorado, with additional sites in Valley Forge, Pennsylvania; Sunnyvale, California; Santa Cruz, California; Huntsville ...

based upon the

A2100AX The A2100 is a model of communications satellite spacecraft made by Lockheed Martin Space Systems. It is used as the foundation for telecommunications payloads in geosynchronous orbit, as well as GOES-R weather satellites and GPS Block IIIA satell ...

design. Among the services carried are

and

Viasat Ukraine Viasat Ukraine is a Ukrainian direct broadcast satellite television distributor. It is owned by "Vision TV". It competes with NTV Plus Ukraine and Poverkhnost which broadcast on the Eutelsat system. The service was launched April 21, 2008 usi ...

which has used the Sirius satellites for their digital platform since its launch. Sirius 4 was renamed to

Astra 4A Astra 4A (originally Sirius 4) is one of the Astra communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transp ...

in June 2010, when the SES took full ownership and control of

Sirius 5

Sirius 5 was the original name of the

SES-5 SES-5 (also known as Astra 4B and Sirius 5) is a commercial geostationary communication satellite operated by SES It was launched on 9 July 2012. The launch was arranged by International Launch Services (ILS). History In October 2008, SE ...

satellite. SES-5 that was launched in July 2012 and is now co-located with

(Sirius 4) at 5.0° East. This satellite provides a similar European and African coverage as Astra 4A. When ordered by the

AB of

Sweden Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...

in October 2008, the name of the satellite was Sirius 5. SES Sirius was acquired by SES in 2010 and the company was named

SES Astra SES Astra SA was a corporate subsidiary of SES, based in Betzdorf, in eastern Luxembourg, that maintained and operated the Astra series of geostationary communication satellites between 2001 and 2011. Formed in 1985 as Société Européenne ...

(a subsidiary of SES). This led to the satellite being renamed to Astra 4B in 2010. The name was changed to SES-5 in 2011.

Retired satellites

Sirius 1

Sirius 1 (later Sirius W) was purchased from

British Sky Broadcasting Sky UK Limited (formerly British Sky Broadcasting Limited (BSkyB)), trading as Sky, is a British broadcaster and telecommunications company that provides television, broadband internet, fixed line and mobile telephone services to consumers a ...

after Sky Television's merger with

British Satellite Broadcasting British Satellite Broadcasting plc (BSB) was a television company, based in London, that provided satellite television, direct broadcast satellite television services to the United Kingdom. It started broadcasting on 25 March 1990. The company ...

(BSB) (the merger was conducted on Sky's terms and BSB's satellites were sold in favour of Sky's leased

Astra Astra (Latin for "stars") may refer to: People * Astra (name) Places * Astra, Chubut, a village in Argentina * Astra (Isauria), a town of ancient Isauria, now in Turkey * Astra, one suggested name for a hypothetical fifth planet that became t ...

satellite operations). The satellite had previously operated as

Marcopolo 1 Sirius was a constellation of communications satellites operated at 5.0° East in geostationary orbit (GEO) by NSAB (later SES Sirius, and now a non-autonomous part of SES, owner and operator of the Astra satellites). They carried digital ...

. It operated at 5.0° East from 1994 until 2000, when it was moved to 13.0° West. It operated here before being moved to a

graveyard orbit A graveyard orbit, also called a junk orbit or disposal orbit, is an Orbit (physics), orbit that lies away from common operational orbits. One significant graveyard orbit is a supersynchronous orbit well beyond geosynchronous orbit. Some satellit ...

in 2003.

Sirius 2

Sirius 2 was manufactured by

Aérospatiale Aérospatiale () was a major French state-owned aerospace manufacturer, aerospace and arms industry, defence corporation. It was founded in 1970 as () through the merger of three established state-owned companies: Sud Aviation, Nord Aviation ...

and launched from

Kourou Kourou (; ) is a commune in French Guiana, an overseas region and department of France in South America. Kourou is famous for being the location of the Guiana Space Centre, the main spaceport of France and the European Space Agency (ESA). It ...

on 12 November 1997 to replace the

Tele-X Tele-X was the first communications satellite serving the Nordic countries. It was launched with an Ariane 2 launch vehicle from Kourou, French Guiana, on 2 April 1989. On 16 January 1998, its fuel was exhausted and it was moved into graveyard ...

satellite. It is of the model Spacebus 3000B2 and has 32 K_u-band transponders with beams targeting both the Nordic region and all of Europe. It was moved to 31.5° East () and renamed

Astra 5A Astra 5A was one of the Astra communications satellites owned and operated by SES at the Astra 31.5°E. Launched in 1997 to the 5° East position by NSAB (Nordiska Satelit AB) (later SES Sirius, and now a non-autonomous part of SES) as Siri ...

on 29 April 2008. The Astra 5A satellite mission ended on 16 January 2009 due to an abnormal condition with the spacecraft.

Sirius 3

Sirius 3 was stationed at 51.2° East at the end if its lifetime () in an

inclined orbit A satellite is said to occupy an inclined orbit around Earth if the orbit exhibits an angle other than 0° to the equatorial plane. This angle is called the orbit's inclination. A planet is said to have an inclined orbit around the Sun if it has a ...

. Sirius 3 was leased to SES immediately after its launch on 5 October 1998 for a period of 12 months (after which it was moved to its original destination of 5.0° East) to provide capacity at 28.2° East and to back up

Astra 2A Astra 2A is one of the Astra communications satellites owned by SES. Launched in 1998 into the 28.2° East orbital position, half its expected end-of-life capacity of 28 transponders were pre-booked by BSkyB, who utilised it to launch their ne ...

, pending the launch of

Astra 2B Astra 2B is an Astra communications satellite, owned and operated by SES. Launched in September 2000 to join Astra 2A at the Astra 28.2°E orbital position providing digital television and radio broadcast services to the United Kingdom and ...

on 14 September 2000. Satellite was retired in 2015 and moved to a

Sirius Satellite Radio

The Sirius satellites are not the satellites used for the American

Sirius Satellite Radio Sirius Satellite Radio was a satellite radio ( SDARS) service that operated in the United States and Canada. Sirius launched in 2002, and primarily competed with XM Satellite Radio, until the two services merged in 2008 to form Sirius XM. Li ...

service, whose satellites are named Radiosat 1-4 due to being launched after the Sirius fleet of satellites.

References

External links

Sirius 1 info from Swedish Space Corporation

Sirius 2 info from Swedish Space Corporation

Sirius 3 info from Swedish Space Corporation
* {{satbeams footprint, 5642, Sirius
SES
- Official SES site
SES fleet information
SES (company) Communications satellite constellations de:SES Sirius