Longest-serving weather satellite moved to ‘graveyard orbit’

The world’s longest-serving meteorological satellite in geostationary orbit has been lifted at least 247km above the geostationary orbit, as part of its end-of-life manoeuvres.  

Launched on 28 August 2002, Meteosat-8 was the first of the Meteosat Second Generation (MSG) meteorological satellites, which marked a major technological advance in satellite meteorology.

Now that its useful life has come to an end, Eumetsat scientists have finalised the process of moving the spacecraft to what is known as the 'graveyard orbit', in order to minimise the risk of collision with operational satellites. 

“At the time Meteosat-8 was designed, guidelines did not exist for the safe disposal of satellites when their operational lifetime ended,” explained Eumetsat director-general Phil Evans.

“Excellent spacecraft design and careful operations enabled us to extend Meteosat-8’s life well beyond the expected 7.5 years. Importantly, we were also able to ensure enough fuel remained on board to move her out of harm’s way of other satellites operating in the Geostationary orbit when we could no longer safely use her."

Meteosat satellites are critical for forecasting rapidly developing severe weather events such as storms. During its operational lifetime, Meteosat-8 produced about a million images of Europe, the whole of Europe and Africa or the Indian Ocean, its islands and surrounding countries. 

Eumetsat currently operates three other MSG satellites – Meteosat-11 and -10 over Europe and Africa and Meteosat-9 over the Indian Ocean.

The first satellite in the third generation of Eumetsat’s Meteosats will soon be launched from Kourou, French Guiana, marking the start of another major technological and scientific advance in satellite meteorology.

As part of the Meteosat-8 decommissioning process, the space organisation also took steps to ensure the long-term stability of the satellite in its new location and minimise the risk that it could break up and generate debris.

Those steps included reducing the satellite’s spin rate, depleting any residual propellant on board and switching off all electrical equipment, in line with current space debris minimisation standards. 

Over the last few years, there has been considerable discussion by space agencies, lawmakers and private companies about how to tackle the problem of space debris, ranging from policy suggestions (such as the introduction of orbital-use fees) to high-tech active space clean-ups (using satellites armed with claws, nets, magnets and other devices).

A recent study published in Nature Astronomy estimated the chance of falling rocket and satellite parts getting through the Earth’s atmosphere, finding there is a one in 10 chance of one or more casualties from space debris occurring over the next 10 years. 

In light of these risks, in September 2022, the US Federal Communications Commission (FCC) voted to reduce the deadline for the removal of unused satellites in low-Earth orbit from 25 years to five.

The rule would apply to satellites launched two years after the order is adopted and would include both US-licensed satellites as well as those licensed by other jurisdictions and seeking US market access. Satellites already in space (such as Meteosat-8) would be exempt.