Russian Progress cargo ship arrives at International Space Station

An unpiloted Russian Progress cargo ship arrived and docked at the International Space Station on Sept. 19. The freighter approached and secured at the space-facing port of the station's Poisk module at 9:44 a.m. EDT (1344 UTC). The docking followed a launch that was delayed by roughly one week to address a technical issue with the Soyuz-2.1b rocket.

Sept. 16 atop a Soyuz-2.1b rocket. Launch preparations had earlier been interrupted when teams discovered a problem in the rocket's third stage. The vehicle was rolled off the pad and returned to its hangar for troubleshooting and repairs before being reinstalled for the successful liftoff.

Roscosmos refers to the vehicle by its Progress MS designation while NASA refers to the mission as Progress 96. The press coverage and imagery released during the operation identify the spacecraft as Progress MS-35 in several reports.

The spacecraft performed a three-day rendezvous profile, completing 49 orbits before final approach. It used the automated Kurs rendezvous system to close in on the Poisk module. Russian cosmonauts Pyotr Dubrov and Anna Kikina were positioned to take manual control using remote controls if Kurs failed to perform, but manual intervention was not required.

At final approach, the docking mechanism's capture hooks were driven closed to complete the hard mate between the Progress and the Poisk port. Docking camera imagery released by mission control shows the freighter's final approach as it aligned and attached to the station's Russian segment.

The mission delivered about 2.8 tons of cargo, including food, fuel, and supplies for the station crew. The freighter is scheduled to remain docked for roughly five months before being filled with trash and deorbited in a controlled reentry, a standard end-of-mission profile for Progress vehicles.

Mission commentary in public coverage noted that the three-day, 49-orbit rendezvous profile was driven by orbital mechanics tied to the launch timing. A three-day approach is less common than two-day or same-day rendezvous profiles but is used when phasing and alignment require additional orbits before final approach.

With docked status confirmed, station teams can transfer the cargo to the outpost. The Progress will remain attached to Poisk for its planned stay of several months to support station operations, resupply needs, and eventual disposal.