Photo courtesy of JPL NASA
NASA rovers on Mars have become something of a permeant part of the average person’s idea of space. Rovers, just like any piece of technology, are capable of errors. The Curiosity Rover experienced one such malfunction on January 20.
The Curiosity Rover landed on Mars on August 6, 2012 and has been operating ever since then, but it is not without its flaws.
“Partway through its last set of activities, Curiosity lost its orientation…Some knowledge of its attitude was not quite right, so it couldn’t make the essential safety evaluation. Thus, Curiosity stopped moving, freezing in place until its knowledge of its orientation can be recovered,” Dawn Sumner, Curiosity team member and a planetary geologist at the University of California Davis, said.
On the Curiosity team’s blog, Sumner further explained the situation in greater detail.
“Rovers also need to know where their bodies are relative to their surroundings Curiosity stores its body attitudes in memory, things the orientation of each joint, which instrument on the end of its arm, and how close APXS [ alpha particle X-ray spectrometer] is to the ground. It also stores its knowledge of the environment, things like how steep the slope is, where the big rocks are, and where the bedrock sticks out in a dangerous way. Curiosity evaluates this information before any motor is activated to make sure the movement can be executed safely…This conservative approach helps keep Curiosity from hitting its arms on rocks, driving over something dangerous, or pointing an unprotected camera at the sun,” Sumner said.
Sumner jokingly summarized the situation as Curiosity having an ‘attitude problem.’ The error did not last long, however. On January 21, the Curiosity team’s blog was updated saying that Curiosity’s problems were solved
“We learned this morning that [our] plan [to fix Curiosity] was successful and Curiosity was ready for science once more,” Scott Guzewich, an atmospheric scientist at NASA’s Goddard Space Flight Center, said.
Guzewich later elaborated on the process of restoring Curiosity’s functionality.
“Much of today’s plan was recycled from last Friday’s intended plan, including contact science with APXS and MAHLI [Mars Hand Lens Imager] on bedrock targets Moffat Hills and Trossachs. There also was a plethora of ChemCam LIBS [laser-induced breakdown spectroscopy] targets, a Mastcam mosaic of Western Butte, Mastcam multispectral images on Trossachs, and ENV movies to search for clouds and dust devils while also documenting atmospheric dust levels…Today’s plan also included a rare measurement with APXS to measure the argon abundance in the atmosphere,” Guzewich said.
Guzewich later went on to describe the measurement process and why it was important in the blog post.
“Approximately 25 percent of Mars, carbon dioxide-rich atmosphere condenses on the winter polar ice cap, while traces gases like argon do not. This leads to seasonal variations in the relative fraction of argon to carbon dioxide in the air. APXS can measure this argon variation by simply turning on and looking at the sky while the arm is stowed. Seeing argon vary through the year is akin to watching Mars breath,” Guzewich said.
In related news, NASA has commissioned a new rover that is scheduled to finish construction sometime in July or August. Whether Curiosity itself might be improved in the future, or if it might get retired after the current rover nears completion, it cannot be denied that its near seven years of operation was groundbreaking for the understanding of other planets. The currently unnamed rover is set to land on Mars sometime in early 2021.