Russia put a trio of military communications satellites into orbit Friday aboard a Rockot launch vehicle, a decommissioned ballistic missile modified for space launches.

The Rockot launcher takes off from the Plesetsk Cosmodrome on Friday. Credit: TV Zvezda
 
The satellites lifted off from the Plesetsk Cosmodrome at 0527 GMT (1:27 a.m. EDT; 9:27 a.m. Moscow time) Friday. The Rockot's Breeze KM upper stage engine delivered the three spacecraft to orbit more than 900 miles above Earth less than two hours later, according to the Khrunichev State Research and Production Space Center, the launch vehicle's prime contractor.

"The liftoff proceeded nominally," Khrunichev said in a press release. "The subsequent phases of payload injection into the target orbit were implemented by means of the Breeze KM upper stage. The satellites separated from the upper stage on Friday, May 23, at the predicted times."

The satellites are part of the Russian military's Rodnik, or Strela 3M, system designed to relay messages between users posted in remote locations. The spacecraft will likely receive the designations Kosmos 2496, 2497 and 2498 under the Russian military's naming scheme for defense-related satellites.

Satellite tracking data indicated a fourth payload was also released into space. Its identity and purpose was not acknowledged by Russian officials.

Friday's flight was the 21st launch of a Rockot vehicle with a Breeze KM upper stage since May 2000.

The Rockot is a modified liquid-fueled two-stage missile built to deliver nuclear payloads to distant targets. Engineers converted the wartime weapon, known to Western observers as the SS-19, to a space launcher by adding a third stage to inject satellites into orbit.

The mission was the 29th space launch to reach orbit this year, and the 11th Russian launch, including the failed flight of a Proton rocket earlier this month.

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