Meteosat

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Meteosat , short for English satellite Meteorological , is a constellation of geosynchronous European weather satellites . The satellites were developed in close cooperation with ESA and are operated by the European organization Eumetsat .

Since the first satellite went into operation in 1977, Meteosat has been providing weather information for the regions of the earth around the prime meridian . The geosynchronous position used at 0 ° geographical longitude and around 36,000 km above the equator is ideal for weather observation over Africa , the eastern Atlantic and southern Europe .

Meteosat data are also made available via the European Copernicus system .

Active satellites

  • Meteosat-11 is almost geostationary at the main position 0 ° above the equator, from where it performs all normal Meteosat tasks. It was activated at the end of 2017 and has been providing data since 2018.
  • Meteosat-10 moves at 9.5 ° East in an orbit inclined by approx. 1 °. He has been performing all normal Meteosat tasks since the end of 2012.
  • Meteosat-9 moves at 3.5 ° East in an orbit inclined by approx. 4 °. On April 9, 2013 he recorded the rapid scan of Meteosat-8.
  • Meteosat-8 oscillates around the position 41.5 ° East at an orbit inclination of approx. 6 °.

Meteosat (first generation) - technology and data

Meteosat (first generation)

The on-board radiometer is the central core of every Meteosat satellite. It supplies the actual measured values ​​of the Meteosat system in the form of radiance from the visible and infrared range of the electromagnetic spectrum .

The first generation satellites all had (and still have) a radiometer as a core component, which measures in 3 spectral bands (or channels).

  • Channel 1: 0.45 to 1.0 microns - The visible band ( vis ible - VIS) is used during the day with two radiometers (VIS1, VIS2) for visual observation.
  • Channel 2: 5.7 to 7.1 microns - The water vapor - absorption band ( w ater v apour - WV) is used to determine the water vapor content in the middle atmosphere.
  • Channel 3: 10.5 to 12.5 µm - The thermal infrared band ( i nfra r ed - IR) is used to determine the temperature of cloud, land and sea surfaces .

Meteosat-1 to -7 delivered every half hour images in a SSP resolution (SSP for S ub S atellite P oint) 5 kilometers (WV and IR) and 2.5 km (VIS) have been scanned. This image data is processed on the ground in less than five minutes and then sent in digital form to customers around the world. The German Weather Service (DWD) in Offenbach am Main is one of these customers .

The solid apogee motor of these satellites was mounted underneath them and was dropped into the GEO upon launch, exposing the radiometer's cooling system. Each of them rotates around its axis 100 times per minute for stabilization. His radiometer scans the earth line by line. The radiation returned from the earth and the clouds is recorded by a complicated mirror system, digitized and transmitted to the primary receiving station in Fucino in Italy . From there the data is forwarded to the control center in Darmstadt . The scan starts at the South Pole and ends 25 minutes later at the North Pole . In the following 2.5 minutes, the mirror system is turned back to the starting position, the satellite remains on standby for 2.5 minutes, so that every half hour a complete image of this region of the earth (Full Earth Scan - FES) is available. In addition, an excerpt showing only Europe was possible, but every ten minutes ( Rapid Scan Service - RSS).

The raw data of these images contain 2500 × 2500 pixels (FES) or 2500 × 864 pixels (RSS). Raw data cannot be received directly without a license key. EUMETSAT first corrects these images and then sends them freely available to customers via EUMETCast and the Internet.

The last active satellite of the 1st Meteosat generation was located over the Indian Ocean. Meteosat-7 was at 57 ° East and provided images of the regions around the 63rd eastern longitude (East Africa, western Indian Ocean, Central Asia) as a replacement for the Insat satellites originally positioned there . He also received reports from the tsunami warning system and passed them on.

Meteosat (second generation) - technology and data

The first Meteosat satellite of the second generation (MSG-1 for short for Meteosat Second Generation ) has been operational since the beginning of 2004 . Astrium is responsible for the main measuring instrument SEVIRI ( Spinning Enhanced Visible and InfraRed Imager ) and the subsystems (power supply, orbit and position control and propulsion) of the satellite. After successfully completing the test phase, it was renamed Meteosat-8 . Meteosat 8 has been working since the second quarter of 2008. It replaced Meteosat-7 in February 2017.

On December 21, 2005, the second MSG satellite was brought into orbit with the help of a European Ariane 5GS launcher. It went into operation in 2006 as Meteosat-9 and is currently (November 2019) at 3.5 ° East. The image size in the HRV channel (SW / panchromatic) is 11136 × 11136 pixels with a spatial resolution of up to 1 × 1 km² in the area of ​​the image center (0 ° north latitude, 0 ° east longitude). The image resolution would thus correspond to a 124 megapixel digital camera . The remaining of the twelve channels produce images with a size of 3712 × 3712 pixels with a resolution of approximately 3 × 3 km² in the image center. Due to the geostationary recording geometry, the resolution decreases towards the edges, or the area of ​​the earth mapped by a pixel increases towards the edges.

Four of the twelve observation channels cover the visible range of light, eight the infrared range. Two of them are in areas where the absorption of radiation by water vapor in the atmosphere is strong. In this way, the weather can be recorded including an estimate of the water vapor content in different layers of the atmosphere. All channels together send 20 times more data to Earth than the previous satellites. The high refresh rate enables an exact prediction of wind direction and speed by comparing two consecutive recordings 15 minutes apart. By combining several channels, different types of clouds (e.g. ice clouds) can be recognized. Snow surfaces can also be clearly distinguished from ice clouds .

The new satellite is to be operated for a total of seven years. More MSG satellites are to follow and will work until 2018.

Details on the MSG telescope Seviri ( Spinning enhanced visible and infrared imager ):

Speed ​​of rotation of the satellite: 100 min −1
Resolution:
3 lines (9 lines high resolution) per scan (rotation)
1250 scans (revolutions) per image, corresponding to twelve minutes per image plus three minutes per image for calibration
Contrast range: 10 bits
High resolution: 5568 × 11136 pixels (1 km resolution)
normal resolution: 3712 × 3712 pixels (3 km resolution)
12 image channels:
2 channels selectively in the visible range from 0.5–0.8 µm
1 channel in the near infrared range 1.5–1.8 µm
1 broadband high resolution channel 0.4–1.1 µm
8 infrared channels 3.4–14 µm
Optical aperture: 50 × 80 cm²
Amount of data: 3.26 M bps

Meteosat (third generation)

The satellites, which are to replace the second generation MSG from 2021 , are called Meteosat Third Generation (MTG) . Due to the number (and weight) of measuring instruments intended for MTG, EUMETSAT decided to distribute them on two platforms (satellites) (twin setup) .

Their tasks were specified in 2006. The following were discussed:

From the beginning of December 2008, details of the MTG program were announced. After that, the first MTG-I with a Flexible Combined Imager (FCI) should start in 2015 . The FCI is an imaging instrument. He should also wear a lightning detection device. The first MTG-S should then start in 2017. The infrared sounder and the visible near-infrared sounder are intended to carry instruments for infrared radiation.

Four MTG-I satellites and two MTG-S satellites are to be built, which according to the latest planning (as of 2019) should start between 2021 and 2032.

After long negotiations on the size of the work share between Germany and France , ESA signed the MTG contract on February 24, 2012 with the main contractor Thales Alenia Space . The three-axis stabilized LUXOR satellite bus for the six satellites is being built by OHB . OHB is also completing the two MTG-S satellites with an infrared instrument from Kayser-Threde , while Tales Alenia Space is installing the MTG-I satellites.

History and future

EUMETSAT headquarters in Darmstadt
  • Early 1970s - The ESA (European Space Agency) begins planning a European weather satellite system.
  • November 23, 1977 - The first European weather satellite Meteosat is launched from Cape Canaveral ( USA ) with a Delta rocket .
  • October 1979 - The radiometer on the Meteosat-1 satellite fails.
  • June 19, 1981 - Meteosat-2 from Kourou ( French Guiana started) out, like all other European satellites. The satellite will be launched into orbit by an Ariane 1 rocket .
  • from 1986 - The processing of the data supplied by Meteosat is taken over by EUMETSAT (Europe's Meteorological Satellite Organization).
  • June 15, 1988 - Meteosat-P2 (P = prototype) was sent into orbit as a makeshift aid because the Meteosat-2 radiometer had failed. (In theory, it can also be called Meteosat-3.)
  • March 6, 1989 - Meteosat-4 is launched into orbit as the first operational satellite (Meteosat Operational Program 1 - MOP 1) of the Meteosat satellite system.
  • March 2, 1991 - Meteosat-5 (or MOP 2) is launched.
  • August 1991 - Meteosat-P2 is temporarily moved to a position at 50 ° W longitude, which it will reach in September. There he supports the American GOES-E .
  • January 1992 - Meteosat-2 has run out of fuel and is being maneuvered from geostationary orbit into cemetery orbit .
  • November 20, 1993 - Meteosat-6 (or MOP 3) is launched
  • December 1995 - Data preparation, project planning and implementation of Meteosat are now completely in the hands of EUMETSAT .
  • December 1995 - Meteosat-3 and Meteosat-4 are placed in a cemetery orbit after the fuel is exhausted.
  • September 3, 1997 - Meteosat-7 (or Meteosat Transition Program 1 - MTP 1), the last Meteosat satellite of the first generation, is launched.
  • Early 1998 - Meteosat-5 is moved to the new position at 63 ° east longitude, as the data from the Indian INSAT actually positioned there are not available.
  • June 1998 - Meteosat-7 becomes the operational satellite (Meteosat-6 is available as a reserve satellite at the same position)
  • August 28, 2002 at 10:45 pm UTC - Successful start of MSG-1 (now Meteosat-8), and thus the beginning of the phase of the second Meteosat generation.
  • November 28, 2002 - Meteosat-8 (formerly MSG-1 ) delivers the first images to Earth. For the first time, 12 channels are now available for weather observation.
  • January 29, 2004 - Meteosat-8 becomes the operational satellite.
  • March 2005 - Meteosat-5 can now receive data from the new tsunami warning system (Indian Ocean Data Collecting - IODC) and forward it to the ground station.
  • December 21, 2005 - Meteosat-9 ( MSG-2 ) is launched.
  • June 14, 2006 - Meteosat-7 will cease its previous service and will be placed over the Indian Ocean to replace Meteosat-5 in the future.
  • April 11, 2007 - Meteosat-9 becomes the operational satellite. Meteosat-8 becomes the reserve satellite.
  • April 26, 2007 - Meteosat-5 is shut down and maneuvered out of geostationary orbit.
  • April 15, 2011 - Meteosat-6 is maneuvered into higher cemetery orbit after its fuel supplies have been used up and shut down. He transmitted the last images to earth on April 11, 2011. Of the satellites of the first generation of Meteosat satellites, only Meteosat 7 is now in service (at 57.5 ° East).
  • July 5, 2012 - MSG-3 is scheduled to be launched from the spaceport in Kourou in French Guiana at 11:36 p.m. Central European Summer Time with an Ariane 5 launcher.
  • August 7, 2012 - Meteosat-10 (MSG-3) transmits the first image during its 6-month trial
  • December 18, 2012 - MSG-3 will be renamed Meteosat-10 after completion of the test (at approx. 3.5 ° West). According to the plans, Meteosat-10 should reach its final position at 0 ° on January 21, 2013 and become the main satellite.
  • July 15, 2015 - MSG-4 is launched into space by an Ariane-5 launcher from the spaceport in Kourou, French Guiana, at 11:42 p.m. Central European Summer Time and is parked at 3.4 ° West.
  • February 1, 2017 - Meteosat-8 replaces Meteosat-7
  • February 20, 2018 - MSG-4 goes into service under the name Meteosat 11 at position 0 °.
  • 2020 - planned end of the life of Meteosat-8
  • 2024 Template: future / in 4 years- planned end of the service life of Meteosat-9 to -11

See also

Web links

Commons : Meteosat  - collection of images, videos and audio files

Individual evidence

  1. ↑ Meteosat-11: Copernicus in Germany , accessed on October 7, 2019.
  2. ↑ Meteosat-10 at N2YO.com, accessed October 7, 2019.
  3. ↑ a b c d e f Eumetsat: Current satellite fleet
  4. ↑ Meteosat-8 on N2YO.com, accessed October 7, 2019.
  5. ↑ Eumetsat: Meteosat Third Generation (MTG) will see the launch of six new satellites from 2021. Accessed on May 19, 2017 (English).
  6. ↑ Press release from Eumetsat ( memento of October 9, 2009 in the web archive archive.today ), December 4, 2008
  7. ^ Gunter's Space Page: OHB: Luxor , accessed on March 22, 2012
  8. ↑ Meteosat Third Generation (MTG) will see the launch of six new satellites from 2021 , Eumetsat, accessed on February 14, 2019.
  9. ↑ Stephen Clark: ESA inks Meteosat contract, ending procurement turmoil , Spaceflightnow, February 25, 2012
  10. ↑ ESA: Europe's youngest weather satellite MSG-3 delivers first image , August 7, 2012
  11. ↑ Eumetsat: Meteosat Orbital Parameters - Email Alert ( Memento from March 17, 2012 in the Internet Archive ), December 26, 2012
  12. ↑ Eumetsat: MSG-3 as Meteosat-10 in action , raumfahrer.net, December 18, 2012
  13. ↑ Astronews: Youngest Meteosat satellite in space, Astronews, July 16, 2015
  14. ↑ Press material on the Ariane launch VA 224 (PDF). Arianespace, July 2015, accessed August 1, 2015.
  15. ^ Meteosat-11. In: d-copernicus.de. Retrieved October 6, 2019 .
  16. ↑ Meteosat - EUMETSAT. Retrieved October 7, 2019 .