LAUREL, Maryland — Pluto’s nitrogen-rich atmosphere appears to be leaking across open space to collect on at least one of the poles of the dwarf planet’s large moon Charon, according to scientists processing data the New Horizons probe sent to Earth shortly before its closest approach to the two bodies.

Mission managers now have settled in to wait for a brief signal Tuesday night that will let them know how the spacecraft fared in its intricately choreographed flyby.

Glen Fountain, New Horizons project manager at the Johns Hopkins University Applied Physics Laboratory, said Monday the spacecraft will hit its 60 x 90-mi. box “almost at the center of it” and right on time.

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Four NASA astronauts, all veterans with experience aboard the International Space Station, space shuttle or Russian Soyuz spacecraft, have been named to train to fly aboard the first U.S. commercial crew missions, tentatively planned for 2016-17.

Dawn responded as designed by stopping all activities (including thrusting), reconfiguring its systems to safe mode and transmitting a radio signal to request further instructions, said Marc Rayman, Dawn's mission director.

Credit: NASA, JHUAPL, SWRI As the New Horizons spacecraft nears its July 14 closest approach to Pluto, the images sent back by NASA’s Long Range…

Details of the critical technology at the core of an innovative hybrid hypersonic propulsion system for air and space systems have been unveiled for the first time by its British-based developer, Reaction Engines.