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Russia launches missile-watching satellite Military personnel at Plesetsk Cosmodrome in Northern Russia launched a Soyuz-2 rocket on May 22, 2020, successfully delivering a classified payload which is believed to be the fourth satellite for the nation's newest constellation designed to provide the Kremlin with early warning about launches of ballistic missiles around the world.
Fourth Kupol/EKS launch at a glance:
Preparations for flight On May 11, 2020, a local publication in the Uvat District of Russia's Tyumen Region reported that the liftoff of the space launch vehicle was scheduled between 10:00 and 12:30 Moscow Time on May 22, 2020, with a backup launch window 24 hours later. The Uvat District hosts a drop zone where the spent second stage of Soyuz rockets impacts the ground nearly 1,600 kilometers downrange from the Plesetsk launch site. The publication asked the residents to stay away from the impact site and said that a search team would arrive there by helicopter to conduct cleanup operations. In the following week, warnings to air and sea traffic were issued closing areas near the Tasmanian coast, as well as in the Ukhta and Tobolsk regions of Russia, where other spent fragments of the launch vehicle were expected to fall. Based on previous uses of the announced drop zones, it is possible to conclude that a Soyuz 2 rocket will be carrying an 14F142 early warning satellite for the EKS OiBU network, whose primary purpose is to detect and track missile launches around the world. Launch profile
Approximate ground track during the launch of the EKS (Tundra) satellite. The launch on May 22, 2020, likely proceeded along the ascent scenario utilized in three previous missions to deploy the EKS constellation. The four-stage Soyuz booster lifted off as scheduled at 10:31:17.291 Moscow Time (3:31 a.m. EDT) from Pad 4 at Site 43 in Plesetsk under the simultaneous thrust of the first and second stages, heading southeast along the southernmost corridor available for orbital launches from Plesetsk. The four boosters of the first stage were jettisoned around two minutes into the flight and probably fell around 350 kilometers downrange, most likely at the S28 impact site located in the marshy area where the Vychegda River flows into the Severnaya Dvina River. The second (core) stage continued the powered ascent. The payload fairing split into two halves and dropped off around a minute after the separation of the first stage. Its fragments probably fell in the Western-Siberian Plain, along the Om River. Less than five minutes into the flight and moments before the second stage completed its burn, the third stage ignited its four-chamber RD-0124 engine, initially firing through the lattice structure connecting the two stages. The second stage then separated and crashed around 1,500 kilometers downrange from the launch site, most likely at the S21 impact site, northeast of the city of Tobolsk. Around nine minutes into the flight, the third stage released the payload section, including the Fregat upper stage and the EKS satellite, into a suborbital trajectory before reentering the Earth's atmosphere. Any surviving debris from the third stage should have fallen into the Pacific Ocean, southeast of Tasmania. Shortly after the launch, the Russian Ministry of Defense confirmed that the assets of the Titov Chief Test Space Center within the Russian Air and Space Forces, VKS, had begun tracking the vehicle at 10:34 Moscow Time, following its on-time liftoff at 10:31 Moscow Time. The separation of the Fregat upper stage from the third stage of the launch vehicle took place at 10:41 Moscow Time, the Ministry of Defense announced. Many eyewitnesses in Tasmania reportedly saw the expected reentry of the third stage over the region. Fregat space tug maneuvers During the orbital part of the launch, the Fregat was expected to conduct three maneuvers to insert the EKS satellite into its orbit. The first maneuver was probably initiated within a minute after the separation from the third stage, placing the stack into an initial parking orbit. The Fregat then fired its engine again to enter a transfer orbit. According to industry sources, the second firing went as planned, parameters of the transfer orbit were reported close to predicted. Finally, the third Fregat increased the apogee to the required altitude for the release of the satellite into a highly elliptical orbit with an orbital period of around 12 hours. The successful release of the satellite into orbit was unofficially confirmed around 15:00 Moscow Time (8 a.m. EDT) on May 22, 2020. The Russian Ministry of Defense announced the successful completion of the satellite delivery around 45 minutes later. The spacecraft received the official designation Kosmos-2546. Following the separation of the EKS spacecraft, the Fregat upper stage typically conducts collision avoidance and deorbiting maneuvers. In turn, the satellite has its own propulsion system to make necessary orbit adjustments. Shortly after the launch, the US military listed two objects associated with the launch, likely representing the satellite and the Fregat stage, in the orbits with the following parameters:
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