GLONASS loses a satellite
A GLONASS satellite has been decommissioned because of a terminal malfunction.
The Russian Federal Space Agency announced on 22 October that it had stopped receiving signals from GLONASS 728 in July - and attempts to fix the malfunction had been unsuccessful. Hence the spacecraft has now been withdrawn from the constellation permanently.
The satellite was launched in 2008 and became operational in January 2009.
There are still 28 satellites in the constellation:
- 24 operational
- 3 spares (1 in each orbital plain)
- 1 under test
GLONASS requires 18 operational satellites for continuous navigation over Russian territory and 24 to provide global cover. So the system is still 'global'.
The Agency explains that, by 2020, it is planned to have 30 Glonass-M and new-generation -K satellites in orbit, including 6 in reserve.
Details from the links below.