A Russian Progress cargo ship, carrying 2.8 tons of supplies and equipment, blasted off from the Baikonur Cosmodrome in Kazakhstan late Friday. It executed a flawless two-orbit rendezvous and docked with the International Space Station just three hours and 21 minutes after launch.
The unpiloted supply ship's Soyuz 2.1a booster roared to life on time at 9:51 p.m. ET (6:51 a.m. Saturday local time), propelling the rocket skyward directly into the plane of the space station's orbit.
After a series of carefully choreographed rendezvous rocket firings, the Progress caught up with the station, lined up on the aft port of the Russian Zvezda module and moved in for a problem-free docking at 1:12 a.m. as the two spacecraft were sailing 260 miles above central Asia.
The Progress delivered 1,543 pounds of propellant to the station, as well as 110 pounds of oxygen, 926 pounds of water and 2,994 pounds of dry cargo, including crew supplies, food and equipment. Expedition 63 commander Chris Cassidy and cosmonauts Anatoly Ivanishin and Ivan Vagner will begin unloading the ship over the next several days.
Next up for the station program are two high-profile launches. The Japanese space agency plans to launch an HTV cargo ship on May 20 carrying a final set of replacement solar array batteries. Then, one week later, NASA and SpaceX plan to launch a Crew Dragon capsule carrying astronauts Bob Behnken and Doug Hurley on a piloted test flight to the station.
That flight, known as Demo 2, is a critical milestone for NASA, the first orbital launch of astronauts aboard an American rocket from U.S. soil since the last space shuttle flight in July 2011.
A successful test flight will clear the way for NASA to certify the Crew Dragon for operational missions, helping end the agency's sole reliance on Russian Soyuz spacecraft for transportation to and from the station.