Gallery: Antares rocket explodes

A commercial Northrop Grumman Cygnus supply ship berthed at the International Space Station fired its main engine for 50 seconds Tuesday in a test of the spacecraft’s ability to reboost, and possibly eventually deorbit, the massive research outpost.

A commercial Cygnus supply ship departed the International Space Station on Friday for an extended mission to deploy five nanosatellites and conduct other experiments before re-entering the atmosphere and burning up with more than two tons of trash.

A 139-foot-tall Antares rocket is slated for a predawn launch Monday from the Mid-Atlantic Regional Spaceport on Virginia’s Eastern Shore, carrying a Cygnus supply ship heading for the International Space Station.