Gallery: Antares rocket explodes

The Antares rocket, Orbital ATK’s medium-class booster now with modern RD-181 engines, launches at 7:45 p.m. EDT (2345 GMT) from NASA’s Wallops Flight Facility on the eastern shore of Virginia.

The first pair of new Russian main engines for Orbital ATK’s modernized Antares rocket has arrived at the company’s Virginia launch base as engineers prepare to return the commercial booster to flight after a catastrophic failure last year.