NASA’s latest Mars rover, Curiosity, is officially on its own after the rover’s California-based team blasted its final commands through 35 million miles of space to prepare the rig for a risky landing. The craft is expected to land on the Martian surface on Monday around 1:30 a.m. EST. During the so-called “seven minutes of terror,” NASA must watch from a distance without any immediate control as the rover enters the red planet’s atmosphere and is lowered down on cables from a hovering jet-powered craft that looks straight out of Star Wars. This video from the Mars Science Laboratory models the rover’s takeoff, 9-month journey, landing, and explorations on the Red Planet:
The Chronicle of Higher Education interviewed Bethany Ehlmann, an assistant professor at Caltech, who designed and will be operating Curiosity’s essential cargo: ChemCam, a remote-controlled laser designed to blast martian rocks to search for traces of water and, ultimately, life. From the Chronicle:
Q. This sounds like a point-and-shoot game, something in a video arcade.
A. I can see that. This is the first time anyone has zapped rocks with lasers on another planet. But it’s a serious scientific instrument called ChemCam.
Q. Do you pull the trigger?
A. Well, the rover pulls the trigger. I’m part of a science team that decides to take an image of a particular rock. We snap it with a telescopic camera. Then the engineers prepare the rover to shoot the laser, usually overnight. Curiosity takes the shot the next morning.
Q. What does all this have to do with water and life on Mars?
A. Mars is cold and dry now. But when we look at rock formations from 3.5 billion years ago, they look like they were part of hydrothermal systems like Yellowstone Park or parts of lake beds. If we were looking at these things on Earth, we’d find signs of microbial life there. So we want to get a closer look. If you were a geologist, you’d chip off some samples and take them back to the lab. Curiosity is our geologist.
Q. A geologist with a laser cannon?
A. It’s our way of getting a closer look. The laser vaporizes a patch of surface, creating a plasma. Light reflecting off the plasma forms a “fingerprint” based on the particular atoms that made up the rock. We can tell from the ratios of these elements if they may have been formed by upwelling groundwater or by settling sediments in a lake. Some rocks are more intriguing than others. If they have a large amount of carbonate in them, for example, they are crying out, “Look at me!” Or a small amount of potassium relative to other minerals is interesting because potassium gets flushed out from rock first if you run water through it.
Q. How often will you fire ChemCam?
A. At the beginning, perhaps just a handful of shots each day as we see how the instrument behaves many millions of miles away. As we grow more confident, perhaps 10 or 15 times a day.
Q. Speaking of confidence, are you sure you’ll get a chance to use ChemCam? A lot of people are worried about this new parachute-and-cable landing technique for Curiosity. It could crash.
A. Mars does eat spacecraft. So I’m both nervous and excited. But our engineers are really, really good. Therefore, on Monday, I plan to be working on the planet’s surface.
Pricing in at $2.5 billion, Curiosity is the most expensive mission NASA has undertaken in recent years and will hopefully best the 2003 missions of twin rovers Spirit and Opportunity, which launched in 2003, with Spirit shortly becoming stuck in the soft Martian soil and rendered inoperable. For now, we can only hold our breath and hope the programmers got Curiosity’s landing right.