posted 11-24-2012 10:06 AM ET (US)        

GLONASS did not reach full operational status until its 24th satellite was launched in 1995. This put GLONASS only one year behind the USA's GPS in reaching that benchmark. However, GLONASS was not maintained by the Russian state, and by 2001 it was down to only six satelites. The early satellites had short life spans and required replacement every three or four years. Economic problems in Russia prevented restoration of the system until just recently.

Now GLONASS has returned to full operation, and since October 2011 has had 24 satellites in orbit. Development of consumer receivers for GLONASS has been much slower than for the USA's GPS, but recently the latest generation of smart-phone devices began to include GNSS receivers with GLONASS capability. The latest GNSS receivers from GARMIN for marine use also have included GLONASS reception.