Live video of launch pad 39A (members only)

A year after a launch mishap left Orbital ATK’s Cygnus supply ship without a ride to the International Space Station, company officials say the cargo delivery system is on the verge of a comeback, thanks to deals with United Launch Alliance and a decision to redesign its Antares booster with new rocket engines.

NASA is sending into orbit Monday night a spacecraft to test a safer type of rocket fuel, an ultra-precise atomic clock that could change the way missions navigate in deep space, and an experiment to examine the resiliency of electronics to radiation.

Take a trip around the perimeter of the Ariane 5 rocket’s launch zone in Kourou, French Guiana, where two Intelsat communications satellites are poised for liftoff Wednesday.