After an 18-hour orbital chase of the International Space Station(ISS), SpaceX uncrewed Dragon spacecraft docked to the zenith port of the orbiting lab's Harmony module on June 6 at 0954 UTC. The capsule, which launched atop a Falcon 9 rocket on Monday (June 5) from NASA's Kennedy Space Center in Florida, was carrying 7,000 pounds of supplies and scientific experiments on board.
Dragon's cargo include two more International Space Station Roll Out Solar Arrays, or iROSAs, which will be installed on the orbiting lab's exterior by spacewalking astronauts to augment its power output.
According to NASA officials, when all the iROSAs are up and running, the space station's electricity generation will be boosted by 20% to 30%.
The science gear delivered by the capsule includes a technology demonstration for autonomous space station docking systems called CLINGER and Genes In Space-10, which will test a way to measure the length of telomeres in microgravity.
Telomeres are regions of DNA at the end of a chromosome. Telomeres shorten as a person gets older, a phenomenon associated with the onset of some cancers and other diseases, as well as general age-related decline.
Also aboard the Dragon are half a dozen cubesats, all but one of which are student-run projects from the Canadian Space Agency's Canadian Cubesat program. The sixth comes from the Aerospace Corporation, in partnership with the Air Force Research Laboratory and Space Systems Command. It's called Moonlighter, and it will provide the platform for a space-based cybersecurity hacking challenge.
SpaceX launched the cargo Dragon atop Falcon 9 rocket on Monday at 1547 UTC. The rocket's first stage returned nine minutes later, back to Earth for a pinpoint touchdown on the company's droneship, A Shortfall of Gravitas, which was stationed off the Florida coast. It was the fifth liftoff and landing for this particular booster, according to SpaceX.
Falcon 9 upper stage deployed the robotic Dragon capsule in low Earth orbit as planned about 12 minutes after liftoff, on Monday.
This is SpaceX's 28th mission for NASA under a series of Commercial Resupply Services contracts -- hence the CRS-28 mission.
Dragon is the only cargo spacecraft capable of making such safe returns. Russia's Progress vehicle and Northop Grumman's Cygnus, are designed to burn up in Earth's atmosphere when their time in orbit is done. "Monday's Falcon 9 launch of CRS-28 to the @space_station marked the 20th mission we've flown a flight-proven Dragon," SpaceX also revealed.
Dragon is expected to stay at the space station for 21 days, then fly back to Earth for a parachute-aided splashdown into the ocean from where it will be retrieved.
WATCH CRS-28 Dragon dock with the space station