TOULOUSE, France – Europe’s 30-nation Eumetsat meteorological satellite organization on June 29 said it would move its aging Meteosat-8 satellite eastward to cover a gap in weather coverage over the Indian Ocean to be created when Eumetsat’s older Meteosat-7 is retired in 2017.

The decision to continue its Indian Ocean Data Coverage (IODC) mission, made by Eumetsat’s ruling council meeting at the agency’s Darmstadt, Germany, headquarters, relieves a source of strain between Eumetsat and the U.S. Air Force.

The Air Force in 2015 expressed frustration that Eumetsat planned to end the IODC mission – which had never been seen as more than a temporary measure – with the 2017 retirement of Meteosat-7.

Since then, Eumetsat has launched another Meteosat satellite, Meteosat-11, and confirmed its in-orbit health, allowing the agency to free up Meteosat-8. Meteosat-8 will be slowly drifted eastward to 41.5 degrees east starting in early July, with its arrival expected in September.

Eumetsat Director-General Alain Ratier answered questions relating to the decision.

What is the health status of Meteosat-8, which you are moving over the Indian Ocean region to continue your gap-filler role in that region?

Meteosat-8 was launched in 2002 and has by far exceeded its design lifetime. Therefore, although the satellite is healthy, our contribution to the Indian Ocean coverage can only be on a best-effort basis,  as was already the case with Meteosat-7. We have fuel to operate it until 2020 if there is no onboard failure.

Is Meteosat-7 still scheduled to be retired in April 2017?

Probably a bit earlier, in the first quarter of 2017. But Meteosat-8 will be in operations at 41.5 [degrees] east before we deorbit Meteosat-7.

Meteosat-8 will operate from 41.5 degrees east. Meteosat-8’s Indian Ocean coverage has been from 57.5 degrees east. Why use a different slot?

The relocation of Meteosat-8 is part of a multi-partner scenario agreed by CGMS [Coordinating Group for Meteorological Satellites, comprised of space agencies with weather satellites in orbit] in 2013 to continue IODC services currently delivered by Meteosat 7 and make them more resilient. This involves satellites from India, Russia and China.

The optimum location for coverage and sampling has always been 40 degrees east given the location of Meteosat-10 at 0 degrees and Insat-3D at 82 degrees east. This allows good overlap for cross-calibration and resilience.

Why did the decision wait until now? Why not announce your intentions earlier?

Everything has been known and published since 2013. We said what we would do and now we are doing it. But a final decision depended on the successful launch, commissioning and in-orbit storage of MSG 4 (now named Meteosat-11), which was achieved in December 2015. We also need to confirm the status of all Meteosat satellites through our annual lifetime review, which was concluded on February.

Our council had decided that the best use of Meteosat-8, at a residual capacity, was support to IODC, but this was on the assumption that it would not be needed around 0 degrees. We had to demonstrate this first.

Peter B. de Selding was the Paris bureau chief for SpaceNews.