With Unfinished Business, NASA Plans More Missions to Mars
The Mars "Curiosity" rover's mission to the red planet has been hailed as a success, so why does NASA want to keep going back to the same place again and again? Scientists at NASA's Jet Propulsion Laboratory explain. Adam Steltzner at NASA's Jet Propulsion Laboratory in Pasadena, Calif., shows Spencer Michels a model of the Mars "Curiosity" rover.
You might think that landing a car-sized vehicle on the surface of Mars might be achievement enough for anyone. But as we will see, nobody in the space business is satisfied with that spectacular success for long.
And it was a major accomplishment that NASA pulled off last August, when the rover "Curiosity" touched down on the Martian surface after an eight-and-a-half month voyage, a project that cost $2.5 billion dollars.
"Curiosity" rover model at the Jet Propulsion Laboratory.
The landing was tricky. If it had gone wrong, it could have broken the rover and the very sophisticated laboratory inside. Things almost did go wrong. The scientists and engineers miscalculated the gravity forces at the landing site, according to project lead Adam Steltzner, and the whole mechanism came down from the sky slightly slower than he had planned. It was an error that didn't have much effect, but, Steltzner says, if the miscalculation had been in the other direction, the lander would have come down faster than planned and hit the surface too hard. Oops.
At the time everyone called the landing perfect, right on target, and the mission, which in simplest terms is a search for water and past life on Mars, is going well. Curiosity began drilling into Martian rocks, something that has never been done before. It will turn those rocks to powder, and the on-board laboratory will analyze their composition.
And the photos the rover is sending back are spectacular: high definition pictures of tiny features of the Martian surface, clearly showing where streams once flowed. Pretty amazing stuff, all of it! And enough to keep scientists busy for years.
So why not be happy with this mission and the several that have preceded it, some on the surface, some orbiting around the Red Planet looking at the big picture?
No, that's not the way science (or NASA) works. The Curiosity mission may be a big success, but there are new worlds to conquer, to coin a phrase. In an interview for the PBS NewsHour, I asked Steltzner why he and his employer wanted to keep going to Mars, again and again:
"Are we alone in the solar system, in the universe? Was there ever life on Mars? Could life have been supported in the environment of Mars? That's the science reason we put that huge Rover on the surface ...The second reason we explore is because it's kind of in our DNA. We have over the span of human existence, explored our universe starting with what's over the next hill, what's over the next ocean, and eventually what is out in space."
Which all leads Steltzner and others at NASA and its Pasadena facility, the Jet Propulsion Lab, to want to do more. For one thing, they are planning to send another rover to the Mars surface in 2020, similar to Curiosity. Perhaps, though nobody is promising, it will be able to pick up Martian soil and rocks and get them back to Earth.
But aren't we already analyzing what's on Mars? Why do we need another rover? That's what I asked Ashwin Vasavada, the deputy project scientist for the mission:
"Each one has more capabilities and more aggressive scientific questions it's asking than the last. This rover asks about are there potential habitable environments in ancient Mars history? ...The next rover in 2020 will most likely ask more direct questions about whether life actually was present in these environments."
The scientists also want to go beyond Mars. Steltzner would love to design a lander for Europa, a moon of Jupiter, and Vasavada concurs:
"Mars isn't the only place where life could exist outside of earth, even in our own solar system. In our neighborhood, Mars is the house next door. So we go there because it's the easiest to look at. But we would love to try the same kind of detection study on a moon of Jupiter like Europa or Titan, a moon of Saturn, both of which also could be habitable environments."
Will NASA do it? That's a touchy question for officials, who are constrained by budgets that are always vulnerable. I asked Fuk Li, the Mars Exploration Manager, what he thought.
"I don't know if I'd say it's in the cards, but it's clearly something we're studying," he said. "The science community has been updating a set of objectives to be accomplished. One of them is to study the Europa moon; the other one is also to look at potentially bringing a sample back from a comet nucleus."
Very exciting goals, and no one's promising the money to make them happen. In fact, recent proposed budget cuts to NASA's planetary science division could curtail space exploration and eliminate the Europa idea. But Li and NASA and allies in the science community keep lobbying to sustain what they are doing: "It is tough, says Li, "but space exploration is something that is kind of innate in the human spirit. You want to go out and see what is the unknown that is out there. And I think we'll continue to do so. "