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Just over two weeks after the CRS-33 cargo delivery to the International Space Station, another cargo ship is now flying to humanity’s orbital outpost, this time from the other side of the world.
Progress MS-32, which rolled out to its launch pad on Monday, Sept. 8, flew atop a Soyuz 2.1a rocket from Site 31/6 at Baikonur Cosmodrome in Kazakhstan. The launch took place on 17:54 UTC on Thursday, Sept. 11, during an instantaneous launch window, as is usual with ISS missions using this launch vehicle.
The Progress cargo spacecraft, massing around 7,280 kg, will spend approximately 48 hours catching up to and rendezvousing with the Station. Progress MS-32 is scheduled to dock to the Zvezda module aft port on the Station’s Russian segment, with the docking currently set for 17:27 UTC on Saturday, Sept. 13.
Progress MS-30 conducting a reboost burn while docked to Zvezda’s aft docking port. (Credit: NASA/Johnson Space Center)
Prior to Progress MS-32’s docking, Progress MS-30 undocked from Zvezda’s aft docking port on Tuesday, Sept. 9, and completed a destructive reentry into Earth’s atmosphere. Before MS-30’s undocking, the International Space Station (ISS) crew loaded the spacecraft with trash; this practice helps keep the Station from being excessively cluttered with old equipment and other unnecessary materials. The Progress spacecraft can carry up to 2,140 kg of trash for disposal.
The docking, as is usual for Progress craft, will be automated, but with a manual backup available for use if needed. To that end, Roscosmos crew members Sergey Ryzhikov and Alexey Zubritsky recently set up a simulator for practicing the use of the tele-robotically operated rendezvous unit (TORU) for manual rendezvous and docking scenarios if the Kurs-NA automated system fails.
The Progress MS-32 spacecraft during processing. Note the red covers over the antennae and other equipment. (Credit: Roscosmos)
The Kurs-NA system is a modernized variant of the Kurs automated docking system, which the Soviet and Russian programs have used for decades. The original Kurs system was initially manufactured in Ukraine. After the Soviet Union fell, the Russian space program sought to develop a system entirely in-country.
Kurs-NA requires just one phased array antenna as opposed to the old system’s use of four phased array antennae. The new system is also lighter and uses less power, with additional computerization, while being manufactured entirely in Russia.
The TORU capability was last used in 2021, when current Station commander, Ryzhikov, used the manual backup to successfully dock Progress MS-16 to the ISS after an issue with weak electrical signals on the Kurs-NA unit during the last 20 m of the spacecraft’s approach.
Progress MS-32 during fueling prior to installation on the Soyuz launch vehicle. (Credit: RSC Energia)
The Progress-MS spacecraft, the latest version of the long-serving Progress cargo carrier, can carry up to 2,600 kg of supplies to the Station. This includes up to 1,800 kg of dry cargo, 870 kg of propellant, 420 kg of water, and 50 kg of gases. The dry cargo typically consists of experiments, clothing, food, and other supplies.
Progress spacecraft docked to the Zvezda aft port are also typically used for Station reboost and debris avoidance maneuvers. However, Cargo Dragon and Cygnus spacecraft can now perform these duties from the U.S. side of ISS.
The CRS-33 Cargo Dragon, using a “boost kit” in its unpressurized trunk, performed a Station reboost test maneuver on Sept. 3 after docking to the Harmony module’s forward port.
Soyuz 2.1a is a three-stage, liquid-fuelled, expendable rocket developed by RKTs Progress and utilized by Roscosmos. Standing 46.3 m tall and 10.3 m wide, Soyuz 2.1a is classified as a medium-lift launch vehicle. The first stage is comprised of four strap-on liquid boosters, each featuring one RD-107A engine. The second stage is the core stage on which the boosters are strapped, featuring one RD-108A engine. Lastly, the third stage sits atop the second (core) stage and utilizes an RD-0110 engine.
The CRS-33 Cargo Dragon prior to docking with ISS. (Credit: NASA)
Soyuz 2.1a can launch 7,340 kg of payload to low-Earth orbit (LEO) from Baikonur and 5,830 kg of payload to polar orbit from Baikonur. Crewed Soyuz missions to the ISS are also launched atop Soyuz 2.1a.
While the astronauts aboard ISS are preparing to welcome Progress MS-32, another cargo mission is being prepared for launch just one day after MS-32’s docking. The Northrop Grumman Cygnus NG-23 spacecraft is scheduled to fly from Space Launch Complex-40 at Cape Canaveral Space Force Station on Sunday, Sept. 14, atop a SpaceX Falcon 9.
(Lead image: The Progress MS-32 and Soyuz 2.1a launch vehicle roll out to the launch pad in Baikonur. Credit: Roscosmos)
