Editing GLONASS (section)

=== Second generation ===
{{main|GLONASS-M}}

The second generation of satellites, known as [[GLONASS-M|Glonass-M]], were developed beginning in 1990 and first launched in 2003. These satellites possess a substantially increased lifetime of seven years and weigh slightly more at {{cvt|1480|kg}}. They are approximately {{cvt|2.4|m}} in diameter and {{cvt|3.7|m}} high, with a solar array span of {{cvt|7.2|m}} for an electrical power generation capability of 1600 watts at launch. The aft payload structure houses 12 primary antennas for L-band transmissions. Laser corner-cube reflectors are also carried to aid in precise orbit determination and geodetic research. On-board [[Caesium standard|cesium clocks]] provide the local clock source. 52 Glonass-M have been produced and launched.

A total of 41 second generation satellites were launched through the end of 2013. As with the previous generation, the second generation spacecraft were launched three at a time using [[Proton rocket|Proton-K]] Blok-DM2 or Proton-K Briz-M boosters. Some were launched alone with [[Soyuz-2|Soyuz-2-1b]]/[[Fregat]].

In July 2015, [[Information Satellite Systems Reshetnev|ISS Reshetnev]] announced that it had completed the last GLONASS-M (No. 61) spacecraft and it was putting it in storage waiting for launch, along with eight previously built satellites.<ref name="issr-20150730"/><ref name="itartass-811771"/>

As on 22 September 2017, GLONASS-M No.52 satellite went into operation and the orbital grouping has again increased to 24 space vehicles.<ref>{{cite news|url=https://www.geospatialworld.net/news/russia-increases-glonass-orbital-grouping-24-satellites/|title=Russia increases GLONASS orbital grouping to 24 satellites|date=2017-10-23|publisher=Geospatial World|access-date=2017-10-23|archive-date=12 July 2021|archive-url=https://web.archive.org/web/20210712015940/https://www.geospatialworld.net/news/russia-increases-glonass-orbital-grouping-24-satellites/|url-status=live}}</ref>