Live coverage: Falcon 9 disintegrates after launch

Orbital ATK’s seventh Antares rocket stands ready for launch with a Cygnus supply ship Saturday on a two-day flight to the International Space Station.

SpaceX’s Falcon 9 rocket is set for liftoff from Cape Canaveral early Tuesday, heading due east over the Atlantic Ocean to deliver the EchoStar 23 communications satellite into orbit 34 minutes later.

George Ricker, an astronomer and pioneer in space imaging sensor ships at MIT, leads the science team for NASA’s Transiting Exoplanet Survey Satellite.