Also hitting the interplanetary highway in 2020 are a trio of first-time Mars explorers, including an unprecedented venture by a private company to reach the Red Planet.
Elon Musk's SpaceX, which already has shaken up the aerospace industry with low-cost pricing and rockets that fly back to Earth for reuse, had planned to launch an unmanned capsule to Mars during the 2018 launch window. However, having just resumed flights in January following an accident, and with much work ahead on a space taxi for NASA, an upgraded rocket motor and the debut flight of a heavy-lift booster, company president Gwynne Shotwell said last month that the Mars mission is being retargeted for the 2020 opening.
SpaceX's Red Dragon mission will join Mars newcomers China, which is developing an orbiter, lander and small rover, and the United Arab Emirates, which is developing a Mars weather satellite called Hope.
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NASA hopes to parlay the simultaneous targeting of Mars by various players into a productive scientific partnerships, but the clock is ticking.
The current network of US rovers and orbiters working at Mars is aging. By the time the new spacecraft arrive in 2021 Curiosity won't have enough power to roam, and NASA's two imaging and communications orbiters will likely "not be capable," said NASA's Mars exploration program director Jim Watzin.
"Sometimes the great success that we've had at Mars ... has obscured the fact that these assets have a finite life," Watzin said at a recent Mars science planning meeting. "It becomes pretty apparent that the era we've all known ... comes to an end at the end of the decade."
Or maybe a new beginning.
Photo: A Proton-M rocket carrying ExoMars 2016 spacecraft blasts off from the Baikonur Cosmodrome.
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