Astra is the brand name for a number of geostationary communication satellites, both individually and as a group, which are owned and operated by SES, a global satellite operator based in Betzdorf, in eastern Luxembourg. The name is also used to describe the pan-European broadcasting system provided by these satellites, the channels carried on them, and even the reception equipment.

At the time of the launch of the first Astra satellite, Astra 1A in 1988, the satellite's operator was known as Société Européenne des Satellites ("European Satellite Company"). In 2001 SES Astra, a newly formed subsidiary of SES, operated the Astra satellites and in September 2011, SES Astra was consolidated back into the parent company, which by this time also operated other satellite families such as AMC, and NSS.^[1][2]

Astra satellites broadcast 2,600 digital television channels (675 in high definition) via five main satellite orbital positions to households across Asia, Australia, Africa, Americas, Europe, New Zealand, Middle East and North Africa.^[3] The satellites have been instrumental in the establishment of satellite TV and the introduction of digital TV, HDTV, 3D TV, and Hybrid Broadcast Broadband TV (HbbTV) in Europe.

A book, High Above, telling the story of the creation and development of the Astra satellites and their contribution to developments in the European TV and media industry, was published in April 2010 to mark the 25th anniversary of SES.

There are 11 fully-operational Astra satellites and another 2 as backup/reserve, the majority in four orbital locations - Astra 19.2°E, Astra 28.2°E, Astra 23.5°E, Astra 5°E. Astra's principle of "co-location" (several satellites are maintained close to each other, all within a cube with a size of 150 km (93 mi).^[4]) increases flexibility and redundancy.

Astra satellites have been designed by Boeing Satellite Systems (formerly Hughes Space and Communications), Airbus Defence and Space (formerly Astrium), Alcatel Space, and Lockheed Martin. The Astra satellites within a family are not identical, for example of the Astra 2 satellites; Astra 2A and Astra 2C are BSS 601HPs, Astra 2B is an Astrium Eurostar E2000+ and Astra 2D is a BSS 376.

The satellites have been launched by Arianespace by Ariane launch vehicles from Kourou, French Guiana, International Launch Services (ILS) Proton launch vehicles from Baikonur, Kazakhstan, and ILS Atlas launch vehicles from Cape Canaveral, Florida, United States. The satellites are launched into an elliptical "temporary transfer orbit" from where they use onboard propulsion to reach their final circular geostationary orbits, at nearly 36,000 km (22,000 mi) altitude. Proton launch vehicles fitted with a fourth stage propulsion unit are capable of launching the satellites several thousand kilometres higher (at the closest point of the elliptical orbit) than Ariane launch vehicles. As a result, most satellites launched in this way have to use less fuel to reach their geostationary orbit, increasing their lifetime.

At the end of 2021, Astra satellite broadcasts were received in 170 million households in Europe.^[85] In Germany, the largest market for Astra broadcasts, 17 million households receive TV via satellite (15.93 million receiving satellite channels in HD) out of 37.22 million TV households (33.76 million HD TV households) in the country with take-up of other TV delivery methods as follows:^[86]

• Astra Digital Radio
• High Above (book)
• HD+
• List of broadcast satellites
• SES Broadband
• MX1
• SES (operator)
• SES Sirius