Photos: Atlas 5 rolls out for launch

NASA’s Juno spacecraft barreled toward a Fourth of July rendezvous with Jupiter after a 1.7-billion-mile, five-year trip from planet Earth. The research probe’s main engine ignited for 35 minutes to maneuver Juno into orbit, and engineers received confirmation of the burn’s conclusion on time at 11:53 p.m. EDT Monday (0353 GMT Tuesday).

An Ariane 5 rocket will fire into the sky from French Guiana just after sunset Wednesday and deliver nearly 12 tons of payload to an orbit reaching 22,000 miles up less than a half-hour later.

A critical test firing Saturday of the four main engines powering the first stage of NASA’s gargantuan Space Launch System moon rocket is the final major hurdle before the fully assembled booster’s costly, oft-delayed launch late this year on an unpiloted test flight.