Progress MS-35 Launches Tuesday as Last Progress Cargo Run on Soyuz-2.1a

Russia's Progress MS-35 cargo spacecraft will lift off Tuesday, September 9, from the Baikonur Cosmodrome in Kazakhstan, carrying more than 5,700 pounds (about 2,600 kg) of food, fuel, water, and equipment to the seven-person Expedition 75 crew aboard the International Space Station. The mission also closes the book on the Soyuz-2.1a rocket's more than decade-long run as the exclusive launch vehicle for Progress MS resupply missions. The next cargo ship in line, Progress MS-36, is confirmed by tracking data to fly on the upgraded Soyuz-2.1b variant for the first time in ISS history, making Tuesday's flight the last of the familiar pairing.Liftoff is currently scheduled for approximately 12:10 p.m. ET (16:10 UTC). If the two-day free-flight rendezvous proceeds normally, Progress MS-35 will dock automatically at the zenith (space-facing) port of the Poisk module on the Russian segment of the ISS at approximately 2:37 p.m.