Curiosity, a one-ton rover on the surface of Mars, completed its first test drive today, covering nearly 23 feet in 16 minutes, including time out for snapshots along the way.
The successful test of the rover's ability to leave Bradbury Landing – the name the science team has given to the rover's landing spot to honor science-fiction writer Ray Bradbury, who passed away in June – marks a significant milestone in the check-out process.
Now the team is preparing to begin what they term an intermission, lasting from a few days to a week. Although the period sounds like Curiosity is getting a break, it isn't. Scientists will use the period to perform initial check-outs of one of two remaining instruments on the first-tests list, as well as put several currently operating instruments through more advanced tests.
When that period ends, it's off to Glenelg, an intriguing junction of three geological features some 440 yards from Curiosity's current location.
Since it landed on the Red Planet early on the morning Aug. 6, Eastern Standard Time, the rover has passed virtually all of its tests so far with flying colors. One glitch cropped up as the ground team tested one of the wind sensors on the rover's weather station. Otherwise, the check-out process has gone flawlessly, mission officials say.
As for the significance of Curiosity's shakedown cruise, the mission's project manager, Peter Theisinger, put it bluntly: "We built a rover, and unless the rover roves, we really haven't accomplished anything."
"The fact that we completely exercised it and everything was on track" means the event marked a "very big moment," he added during a briefing on Wednesday at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
After demonstrating that its wheels had their full range of steering motion Tuesday, Curiosity covered about 15 feet early Wedensday before it stopped and performed a 120 degree turn. It took time out to capture images of its tracks, then threw itself into reverse for another 8 feet before calling it a day.
Curiosity's new parking spot puts it in a good position to explore Goulburn – one of four regions around Bradbury Landing scoured when the the rover's rocket-powered "skycrane" hovered above the ground as it lowered Curiosity to the surface via tethers.
The science team is thinking about spending a few days examining Goulburn and the other skycrane scours with three of the rover's 10 instruments.
Goulburn is one of two targets the rover's ChemCam has zapped with its laser, which vaporizes material it zaps. Light from the tiny bursts of plasma the laser generates carry information on the material's chemical composition, which spectrometers inside Curiosity's body reads.
The laser's first target, a 3-inch rock dubbed Coronation, proved to be basalt – a type of rock that forms as magma cools and hardens. After taking the chemical measure of Coronation, ChemCam's science team had Curiosity zap three locations on exposed bedrock at Goulburn and found more basalt. But the points the laser hits cover a patch of rock surface about the size of a pin head, so researchers are interested in using a suite of three instruments, including ChemCam, to give Goulburn and its three amigos – Burnside, Hepburn, and Sleepy Dragon – a close look.
Although Glenelg is only 440 yards away, it's likely to take weeks to get there. Along the way, if the team runs across fine-grained material, it will stop and use the deposits to test the Curiosity's ability to scoop samples and deliver them to its internal chemistry labs, says Joy Crisp, the rover's deputy project scientist. Researchers have talked about a one-month stay at Glenelg.
"After Glenelg, we head for Mt. Sharp," she says. "That will be a much longer drive, perhaps with some brief stops along the way.
That leg of Curiosity's journey is likely to take several months, she says.