00:14SES, Société Européenne des Satellites, est l'entreprise d'Astra.
00:20Astra, un système de satellite qui est créé pour la distribution de télévision et de radio dans l'Europe.
00:32Creté en mars 1985 et basé en Luxembourg, SES est l'opération d'Europe d'un premier satellite de l
00:38'Operateur.
00:39La company operates under a franchise agreement with the Grand Duchy.
00:44SES' headquarters are located at the Château de Betzdorf,
00:47a former residence of the Grand Duke of Luxembourg.
00:56La company employs over 140 staff from more than 10 different nations.
01:08Next to the administrative building are located the Astra Ground Control Facilities,
01:13with the large parabolic antennas which are used to control and steer the satellites in space,
01:18as well as to transmit video and audio signals to the satellites.
01:31A separate antenna is used for each of the Astra satellites.
01:40The Betzdorf site also comprises various communications antennas for the reception and transmission of TV and radio signals.
01:48Société Européenne des Satellites has several subsidiaries in Europe.
01:52In Germany, in Frankfurt.
02:01In the UK, in London.
02:09In Spain, in Madrid.
02:23The six co-located satellites in the Astra system, of which three are already in operation,
02:28feature a reliable technology as well as advanced satellite design.
02:34Every satellite is constructed individually,
02:37and it takes highly qualified specialists about three years to build an Astra satellite weighing approximately three tons.
02:45The satellite is very sensitive and needs to be assembled in a completely dust-free environment.
02:52Each part undergoes rigorous testing to ensure that it functions perfectly on its own and as part of the system.
02:58Precision testing at ground level ensures that the satellite will perform perfectly in space.
03:20The Astra satellites were launched into space from the European Space Centre in Kourou, French Guiana.
03:26The launch facilities, located at five degrees latitude north, are optimal for launching satellites into equatorial orbit.
03:38The launch site of Kourou also offers sophisticated facilities to prepare and test the satellites prior to launch.
03:53The spacecraft are also fueled on site.
03:56It's this fuel which allows the spacecraft to be propelled into geostationary orbit, as well as the subsequent station-keeping
04:03maneuvers.
04:05The satellite is then placed in the top capsule of the Ariane 4 launch vehicle, which puts the Astra satellites
04:11into orbit.
04:20On December the 11th 1988, Ariane Space Flight 27 successfully injected the Astra 1A satellite into geostationary transfer orbit.
04:29A whole new era in satellite television had begun.
04:35A whole new era in satellite television had begun.
04:59with the Astra 1C on May the 11th 1993, with Ariane flight number 56.
05:14The launch of a spacecraft on board an Ariane rocket can be summarised as follows.
05:1920 minutes after take-off, the Astra satellite is injected into geostationary transfer orbit near the equator.
05:24The closest point from the satellite to the Earth is about 200 kilometres, and the furthest 36,000 kilometres.
05:37Helped by the firing of on-board thrusters, Astra is then propelled from transfer orbit into geostationary orbit.
05:45Thereafter, the satellite unfolds its 10-metre-long solar panels, which will supply the energy for the electronic systems.
05:59In low Earth orbit at a height of 300 kilometres, a satellite will revolve every one and a half hours,
06:05and spin faster than the Earth.
06:09The Moon, which is in a high Earth orbit, revolves only once every 28 days.
06:15So positioned between these two in geostationary orbit at a height of 36,000 kilometres,
06:21Astra spins at the same speed as the Earth, and is therefore always seen in the same position above the
06:27equator.
06:29The optimal geostationary position for Astra is within a 140-kilometre cube.
06:35In this position, the Astra satellites are slowly but constantly moved by the elements.
06:41However, on-board thrusters controlled from the ground can be fired to correct Astra's position at any time,
06:47and keep it positioned at 19.2 degrees east.
06:51The rocket fuel on-board is sufficient to last the approximate 12 years or more of a satellite's life.
06:58The Astra system currently consists of three co-located satellites.
07:03Three additional satellites are scheduled to be launched in 1994, 1995 and 1996 respectively.
07:11With every new Astra satellite, a whole range of additional television and radio programmes will be added to the system.
07:20The Astra footprint covers the greater part of Europe, from Scandinavia down to Italy,
07:25and from Spain, including the Canary Islands, across to Eastern Europe.
07:41Television and radio operators broadcasting via Astra transmit their programmes to uplink stations at the locations shown here.
07:49The signals are then sent from these uplink stations directly to the Astra satellites.
07:58The uplink is carried out via antennas like the ones shown here in Betzdorf.
08:09The fixed antennas on the ground see the satellites as a single fixed point in the sky,
08:14so when the picture arrives on your screen, it has already travelled 72,000 kilometres at the speed of light.
08:26On June 7, 1988, Sky Television announced its decision to take four Astra transponders,
08:33and became Astra's first client.
08:35Since then, the 50 transponders of the current system have all been leased by various European and international programmers.
08:44Today, the Astra satellite system already offers you a wide choice of television programming,
08:49by country, by language and by special interest, be it general entertainment or thematic television,
08:56subscription services or programmes transmitted in the clear.
09:01Additional audio subcarriers enable each channel to carry simultaneous language soundtracks for television or stereo radio channels.
09:10Astra offers alternative television and radio for everyone.
09:30This is the control centre at Betzdorf, where communication with the Astra satellites is maintained around the clock.
09:38The control centre ensures the perfect functioning of the Astra satellite system.
09:42The huge parabolic antennas are positioned to face directly towards Astra.
09:47They control and steer the satellites in space, and also uplink programmes.
09:52On request, Betzdorf can also provide transfer orbit services or in-orbit testing support to other satellite operators.
10:00The Astra satellites are monitored and steered from one of these control units, equipped with at least two or three
10:06backup units.
10:11All operations are coordinated by a team of multinational professionals.
10:32In addition to the monitoring of the satellites in orbit, the technical quality of the video and audio transmissions needs
10:39constant surveillance.
10:40The individual channel transmitters on the satellites are called transponders and are monitored from this control room.
10:47If a transponder suffered technical problems, the signal would immediately be switched over to a backup amplifier so there would
10:53be no loss in transmission.
10:55Professional control of the transmission quality is provided 24 hours a day.
10:59The network operations centre uplinks a significant part of all the television and radio channels to the Astra satellites.
11:09In addition to its satellite control facilities, SES operates a completely autonomous backup station providing operational security to the system.
11:28Astra reception is as easy as ABC.
11:31For direct-to-home reception, all you need is a small fixed-dish antenna of 60 centimetres or more,
11:36correctly aligned on the orbital position of the satellites.
11:45A satellite receiver, both elements for less than the price of a good video recorder, as well as your existing
11:51television set.
11:56If you live in a group of houses or a block of flats, you can invest together in a shared
12:01Astra reception system,
12:02so that everyone can receive the Astra program choice.
12:09There are also built-up areas where viewers may be able to get connected to a local cable network,
12:14which carries the Astra programming underground.
12:19Astra offers a real alternative for some 75% of European households located in non-cabled areas,
12:26who have no access to a wide program choice.
12:28The simplest way to get more television choice is to take the initiative yourself.
12:40Astra is close to you.
12:42Through its active marketing, Astra provides consumers with detailed information about the program offer
12:47and optimal ways of reception.
12:54The company also participates in fairs and exhibitions.
12:58Organizes seminars for retailers and installers.
13:04Works in parallel with program providers.
13:11Works closely with the industry on the technical specifications of Astra reception equipment.
13:17And collaborates with the retail and installation trade throughout Europe.
13:36The Astra system has been designed for the future needs and demands of audiences all across Europe.
13:42The satellites currently in operation and those already under construction ensure the continuation of this system well into the next
13:48century.
13:49Whatever technology comes along, Astra is ready and waiting.
13:54By co-locating additional satellites at the same orbital position of 19.2 degrees east,
14:00and by using digital compression in the near future,
14:04Astra will be able to offer an even greater number of programs, all available on a single fixed antenna.
14:11The television of the future will give consumers the opportunity to select from an ever-increasing choice of quality programs.
14:30Astra.
14:31More channels.
14:33More choice.
14:35Astra.
14:35More obesitas
15:04West
15:04Motivation
15:04Tokyo
15:04The
15:05– Sous-titrage FR 2021
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