In conjunction with the Global Atmospheric Research Program (GARP), ESA developed and maintains geostationary meteorological satellites of the Meteosat series. Three pre-operational spacecraft were launched in 1977, 1981, and 1988, respectively, before the Meteosat Operational Program (MOP) was initiated with the orbiting of Meteosat 4 in 1989. Although ESA originated and continues to control the Meteosat network, the 16-member European Organization for Meteorological Satellites (EUMETSAT), created during 1981-1986, is now responsible for the system. Beginning with Meteosat 4, EUMETSAT is the legal owner of the series satellites.
Meteosat satellites closely resemble their American and Japanese counterparts. Each spacecraft has a mass of about 320 kg on station in the form of a 2.1-m-wide, 3-m-tall, spin-stabilized (100 rpm) stepped cylinder. Solar cells cover the majority of the spacecraft surface providing a minimum of 200 W of electrical power. The satellite design life is three years with consumable supplies for at least five years. The prime contractor for Meteosat is the French firm Aerospatiale with major subcontractors DASA, Matra Marconi, and Alenia Spazio.
The primary Meteosat payload is a 40-cm diameter, 3-band, imaging radiometer sensitive to visible light (0.5-0.9 µm), IR (10.5-12.5 µm), and water vapor (5.7-7.1 µm). Resolution for the visible band is 2.5 km, while that for the other two bands is 5 km. A single image requires a scan time of 25 minutes with a limit of 48 images per day. Meteosat also carries a 66 channel capacity data collection service package to receive local environmental information. Data collection platform reports from 4,000 sites are forwarded by Meteosat to the primary control center at Odenwald, near Darmstadt, Germany, for further distribution (References 487-492).
In early 1993, the operational Meteosat constellation consisted of three spacecraft: Meteosat 3 (aka Meteosat P2) near 75 degree W. Meteosat 4 (aka MOP 1) near 0 degrees E, and Meteosat 5 (aka MOP 2) near 4 degrees W. Meteosat 3 had just arrived at its far Western Hemisphere location in February to assist the US which was experiencing difficulties with its own GOES (Geostationary Operational Environmental Satellite) system and remained there through the end of 1994 (References 491 and 493).
Meteosat 4, despite some imaging difficulties encountered early in life (launched in June 1989), was serving as the Meteosat prime spacecraft since its planned replacement, Meteosat 5, was having more serious imaging problems of its own. The launch of Meteosat 6 (aka MOP 3) on 20 November 1993 by Ariane was to help remedy the situation by replacing Meteosat 4 and allowing Meteosat 5 to relieve Meteosat 3. However, Meteosat 6's IR radiometer experienced malfunctions from the outset. The decision was then made to move Meteosat 5 into the prime location at 0 degrees E in February, 1994, and place Meteosat 4 in standby at 8 degrees W. Meanwhile, Meteosat 6 was left at 10 degrees W to permit the development of corrective measures for the radiometer problem (References 494-499).
The next Meteosat, scheduled for launch in mid-1996, will support the Meteosat Transition Program (MTP), which encompasses major programmatic as well as technical changes. At the end of 1995, EUMETSAT will take full responsibility of the MOP and MTP spacecraft from ESA. At the same time, development of the Meteosat Second Generation (MSG) is underway with an anticipated maiden launch about the year 2000. ESA will supervise the production of the first MSG vehicle and then turn the entire program over to EUMETSAT. Each MSG spacecraft will have increased wavelength fidelity (up to 12 bands), better resolution (as low as 1 km), more rapid imaging (15 min per full scan), and greater spacecraft longevity (at least twice that of MOP satellites). Phase B activities for MSG, which will look very similar to MOP but be twice as large, got underway in 1994 with joint funding from ESA and EUTMETSAT (Reference 499).
488. MOP 2, ESA and EUMETSAT, January 1991.
489. METEOSAT, Aerospatiale, 1992.
490. EUMETSAT Annual Report 1991, EUM AR 04, EUMETSAT, 1991.
491. "Meteosat Programme", Spaceflight, October 1993, p. 337.
492. P.B. de Selding, "Study Says European Weather Satellite Buoys Industry", Space News, 15-28 November 1993, p.21.
493. P.B. de Selding, "Meteosat Ready To Aid U.S. Weather Coverage", Space News, 1-7 March 1993, p.6.
494. "European, Mexican Payloads Set For Arianespace Launch", Aviation Week and Space Technology, 15 November 1993, p. 30.
495. "Meteosat 6 Assessment", Aviation Week and Space Technology, 3 January 1994, p. 13.
496. "Outlook Bright for Weather Forecasts, Spaceflight, February 1994, p. 71.
497. "Inquiry Board To Investigate Meteosat 6 Anomaly", Space Business News, 15 March 1994, p. 4.
498. "Meteosat 6", Space News, 12-18 December 1994, p. 23.
499. '94 Annual Report', ESA, 1995, pp. 41-45.