Finally, in 2020, NASA will attempt to put another Curiosity-size rover on Mars. It is widely expected to begin a campaign to achieve one of the holy grails of space science: eventually return a rock or soil sample from Mars. It's an objective that just a few months ago had been axed from NASA's budget.
"It's huge," says Dr. Hubbard of the recent announcement of the 2020 mission.
The technology honed and science gleaned from these missions, past and future, will also add to the knowledge humans will need if they are ever to achieve one long-sought dream: to walk on Mars and perhaps eventually colonize it. While both political and practical problems make a manned mission to Mars seem remote for now, the idea remains a source of fascination and planning in scientific circles and space agencies around the world.
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Mars is certainly a tough destination to reach. The grimness in the mission control room in 1999 is a reminder of that. Human error, technical glitches, and the challenge of orchestrating a rendezvous between two objects after traveling more than 300 million miles, at speeds of up to 50,000 m.p.h., make landing a craft on Mars or orbiting it very difficult. This is to say nothing of dust storms, wayward winds, and frigid temperatures once a spacecraft lands.
The result is that, in the 52 years since humans have been trying to send spacecraft to Mars, only 36 percent of the missions have achieved their primary objectives. That includes 40 launches by a variety of entities – Russia, the US, Europe, and Japan.