Aging Meteosat-7 Is Latest in Series of Eumetsat Craft Covering Indian Ocean Region

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CANNES, France — Europe’s Eumetsat meteorological satellite organization will place its Meteosat-7 satellite into a retirement orbit in April 2017 — by which time it will have lasted four times longer than its planned service life — by assuring that it retains enough residual fuel to climb several hundred kilometers above the geostationary-orbit belt.

Launched in September 1997, Meteosat-7 started at Eumetsat’s core zero degrees orbital slot over Europe and was built to operate for five years.

When Darmstadt, Germany-based Eumetsat, Europe’s weather satellite agency, launched subsequent capacity and Meteosat-7 was no longer needed for the agency’s core mission, Eumetsat agreed to fill a coverage gap over the Indian Ocean region.

Starting in 1998, the Meteosat-5, Meteosat-6 and more recently the Meteosat-7 satellites were moved to slots over the Indian Ocean — the only one of five major meteorological regions that was lacking sufficient coverage.

Meteosat-7 arrived at its current location at 57.5 degrees east longitude in July 2006.

Eumetsat has been consistent in telling its international partners that what it calls the Indian Ocean Data Coverage (IODC) mission is a best-efforts undertaking that would be continued only to the extent that Eumetsat continues to have spare in-orbit capacity.

The IODC mission was made necessary in part because of an in-orbit failure of a Russian meteorological satellite and the occasional difficulty the international meteorological satellite community had in getting full Indian weather satellite data sets put into the global World Weather Watch system.

Clemens Kaiser Eumetsat
Clemens Kaiser, Eumetsat’s program development director. Credit: Eumetsat

Clemens Kaiser, Eumetsat’s program development director, said current plans are to keep Meteosat-7 in service through 2016 before raising it into the retirement orbit in keeping with international space debris-mitigation guidelines.

Eumetsat in January estimated that Meteosat-7 had 6.38 kilograms of fuel remaining, of which 3.9 kilograms would be reserved for the orbit-raising maneuver in April 2017. Eumetsat has said its experience with the nearly identical Meteosat-5 and Meteosat-6 satellites has given it confidence in its fuel-assessment accuracy.

Kaiser was attending a briefing here to mark the imminent shipment to launch sites of three Earth observation spacecraft built by Thales Alenia Space, whose main production facility is located here.

The Meteosat Second Generation-4 satellite for Eumetsat, which spent five years in storage because it was not needed in orbit, is scheduled for launch aboard a European Ariane 5 heavy-lift rocket on July 2.

The long-delayed Jason-3 ocean-altimetry satellite, a joint U.S.-European program including Eumetsat and the U.S. National Oceanic and Atmospheric Administration, is scheduled for launch the evening of July 21 or July 22 aboard a SpaceX Falcon 9 rocket from Vandenberg Air Force Base, California.

Officials here said that while the launch is more than a year late, the Jason-2 satellite in orbit has managed to remain functional well beyond its expected retirement date. As a result, users of Jason-2 should be able to transition to Jason-3 with no gap in data continuity, said Philippe Escudier of the French space agency, CNES.

Meteosat-7 Cyclone Bansi
Animation of images captured by Meteosat-7 in mid-January 2015, of Cyclone Bansi in the Indian Ocean. Credit: Eumetsat

CNES and NASA began the ocean-altimetry program in the early 1990s with the Topex-Poseidon mission, followed by the Jason series that subsequently won the financial support of NOAA and Eumetsat.

The third Thales Alenia Space-built satellite being readied for shipment is the Sentinel-3A, scheduled for launch in October aboard a Russian Rockot vehicle from Russia’s Plesetsk Cosmodrome.

Sentinel-3A is part of the European Commission’s elaborate Copernicus environment monitoring program, which features a fleet of Sentinel satellites carrying different sensors.

Another Jason-type satellite is being designed by the European Commission as part of Copernicus and now awaits final financial backing from Eumetsat. Kaiser said the agency’s ruling council is scheduled to take up the subject — the satellite is called Sentinel-6/Jason Continuity of Service — in June.

Having stepped back from the Jason program of recurrent-model satellites to provide service continuity to a growing list of commercial, civil and military users, CNES and NASA have agreed to develop a next-generation mission called SWOT, or Surface Water and Ocean Topography.

The $1.1 billion SWOT satellite is tentatively scheduled for launch in 2020, with NASA taking a majority stake in the mission. Thales Alenia Space has won an initial contract for development and integration of the satellite’s platform. SWOT takes ocean-height monitoring to the next level to assess rivers and lakes in addition to larger bodies of water.

CNES is also developing jointly with the China National Space Administration an ocean-altimetry satellite called CFOSat, or China-French Oceanic Satellite, scheduled for launch in 2018.