Commercial geostationary satellites are staying in orbit longer than ever, and well beyond their original design lives.
A study from Roger Rusch, president of research firm TelAstra, In essence, Rusch says that while ten years ago in 2009 there were an average of 15 per cent of satellites with extended lives in orbit, today the situation has more than doubled to more than 30 per cent of geostationary craft.
This situation is likely to continue and will be helped in part by the addition of so-called ’Space Tugs’. Intelsat, for example, has already made use of one Mission Extension Vehicle (MEV-1, from Northrop Grumman) and is about to launch a second on an Arianespace flight.
MEV-1 was sent to help Intelsat 901 in February, a craft that was already served for 19 years. MEV-1 will extend that mission by another 5 years.
These Mission Extension Vehicles attach themselves to a target satellite which might be working perfectly well other than it might be running out of fuel, or has suffered a malfunction of some sort but where its core transmission ability remains operational.
One powerful aid to existing satellites is good husbandry of a satellite’s fuel, and greater use of electric propulsion while in orbit.
TelAstra cites Iridium as an example and where its first Generation 1 satellites, even though only designed for 7-year missions, but some of the fleet lasted around 20 years in orbit.