Watch SpaceX launch private Cygnus cargo craft to ISS Aug. 4 after delay

A Falcon 9 rocket is scheduled to launch Northrop Grumman’s Cygnus freighter from Cape Canaveral Space Force Station in Florida Sunday at 11:02 a.m. EDT (1502 GMT). That’s a one-day delay; the launch had been targeted for Saturday (Aug. 3), but it was pushed back due to unfavorable weather.

You can watch the action live here at Space.com, courtesy of NASA. Coverage will begin about 20 minutes before liftoff.

Sunday’s launch will kick off the NG-21 mission, so named because it will be the 21st Cygnus cargo flight to the ISS.

The Cygnus vehicle that’s flying on NG-21 is called the S.S. Richard “Dick” Scobee, after the NASA astronaut who commanded the ill-fated STS-51-L mission of the space shuttle Challenger. Scobee and his six crewmates died when Challenger exploded shortly after liftoff on Jan. 28, 1986.

Related: Facts about Cygnus, Northrop Grumman’s cargo ship

The freighter is packed with nearly 8,200 pounds (3,720 kilograms) of supplies on NG-21, including a range of scientific gear. Among the experiments are Rotifer-B2, which will study the effects of spaceflight on DNA repair in the rotifer species Adineta vaga, and MVP Cell-07, which will examine how bioprinted or engineered liver tissue behaves in microgravity.

Two tiny cubesats are hitching a ride to the ISS on NG-21 as well, as part of NASA’s ELaNa (Educational Launch of Nanosatellites) program. The pair will deploy from the ISS after the Cygnus docks.

The S.S. Richard “Dick” Scobee is expected to remain docked with the ISS until January 2025, when it will depart to burn up in Earth’s atmosphere.

Russia’s Progress freighter is similarly disposable; the third currently operational ISS cargo craft, SpaceX’s Dragon capsule, is reusable, landing safely in the ocean under parachutes at the end of its missions.

Editor’s note: This story was updated at 11:10 a.m. EDT on Aug. 3 with news of the launch delay and the new target date of Aug. 4.