Mars Curiosity rover leaves coded tracks on first test drive
NASA's Mars rover Curiosity has left its first tracks in the Martian soil, imprinting the coded mark of its maker in its trail.
On Wednesday, the car-size, six-wheeled rover took its first test drive since arriving on the Red Planet more than two weeks ago. Its drivers back on Earth ordered Curiosity to roll forward about 15 feet, (4.5 meters), turn right and then back up about 8 feet (2.5 m), such that when the robot stopped it was positioned to the left and roughly perpendicular to where it touched down inside Mars' Gale Crater.
The track pattern — dot-dash-dash-dash, dot-dash-dash-dot, dot-dash-dot-dot (".--- .--. .-..") — spells out "JPL" in Morse code, which translates letters and numbers into a series of short ("dot") and long ("dash") signals.
Curiosity's signature wheel-print was a nod to NASA's lead center for unmanned planetary exploration, which built the rover and now commands it as Curiosity prepares to explore Mars in search of conditions habitable to past or present life.
The dashes and dots are more than just an autograph on the ground. They serve as "visual odometry" marks, which allow Curiosity's engineers to determine the position and orientation of the rover, as well as how far it traveled, by analyzing images of its tracks.
"We have intentionally put holes in the wheels to leave a unique track on Mars," Heverly said. "So if we are in sand dunes where we don't have lots of rock features around us, we can use those patterns to do our visual odometry."
In addition to the Morse code JPL, Curiosity's wheels also feature a zigzag cleat pattern.