Russia’s Soyuz-2-1a rocket made its first launch of 2020 on Thursday, carrying the ninth Meridian communications satellite into orbit. Having lifted off from the Plesetsk Cosmodrome in northern Russia at 08:24 UTC, Soyuz deployed its Fregat-M upper stage about nine minutes later to carry the satellite to its final elliptical orbit. Spacecraft separation is expected to occur two hours and twenty minutes after launch.
Meridian is a network of satellites that provide the Russian Government with communications for military and installations in the country’s far northern regions. The Meridian constellation forms part of Russia’s Integrated Satellite Communications System, complimenting the geostationary Globus – or Raduga – series of communications satellites.
While geostationary satellites are usually the most convenient way to establish satellite communications between fixed sites, regions close to the Earth’s poles can present challenges to their successful use. At these high latitudes geostationary satellites appear close to the horizon making their use impractical or impossible depending on how far north the receiver is located. Meridian satellites instead use a special class of highly elliptical orbit, known as a Molniya orbit, to ensure the spend most of their time over the northern hemisphere.
The Molniya orbit is named after an ...