Progress MS-16 and Pirs Undocked from International Space Station

Progress MS-16 and the Pirs module after undocking from the International Space Station. (Credit: Roscosmos)

MOSCOW (Roscosmos PR) — In accordance with the flight program of the Russian segment of the International Space Station, today, on July 26, 2021, the Progress MS-16 transport cargo vehicle with the Pirs docking module undocked from the ISS.

Pirs will be replaced by the Nauka Multipurpose Laboratory Module, which was successfully launched from the Baikonur Cosmodrome on July 21, 2021 and is now on its way to the International Space Station. Nauka is due to dock with the station on Thursday, July 29.

Upon completion of preparations for undocking at 10:53 UTC, the TsNIIMash Mission Control Center specialists (part of Roscosmos) issued a command to undock the spacecraft. According to the standard program, the Progress MS-16 cargo vehicle and the Pirs module departed from the nadir port of the Zvezda module of the ISS Russian segment at 10:55:33 UTC.

After diverting the craft to a safe distance from the station, the Chief Operating Control Group specialists (RSC Energia, part of Roscosmos) began the controlled deorbit of the spacecraft and the module into the Pacific Ocean. Roscosmos had completed all the necessary procedures to establish this area as temporarily dangerous for navigation by sea and by air.

At 17:01 Moscow time, Progress MS-16 turned on its main engine for braking. After working for 17.5 minutes, the engine gave the vehicles braking impulse of 120 m/s. At 17:42 Moscow time, Progress MS-16 and Pirs entered the dense layers of the Earth’s atmosphere. After another 10 minutes, the fireproof elements were sunk into the “cemetery of spaceships” in the non-navigable part of the Pacific Ocean – 3,600 km from the city of Wellington, New Zealand and 5,800 km from the city of Santiago, Chile.

The Pirs module was used as a docking module for the Russian Soyuz crewed and Progress cargo spacecraft. In addition, until November 2020, cosmonauts performed spacewalks from Pirs under the Russian ISS program, while in November 2020 and June 2021, the Russian crewmembers used the neighboring Poisk module for these purposes.