It’s been fairly quiet as the Mars Science Laboratory (MSL) rover Curiosity continues driving towards the point at which it is hoped the rover can traverse between a line of low-lying sand dunes and start exploring the lower slopes of Aeolis Mons, which NASA has dubbed “Mount Sharp”.
However, Thursday November 7th saw an unexpected hiccup in proceedings as Curiosity unexpectedly performed a “warm reset” (software reboot). This occurred around four and a half hours after the new flight software uploaded to the rover (see my last mission report) had been temporarily loaded into memory as a part of the uploading and commissioning of the software, and while the rover was also transmitting data to the Mars Reconnaissance Orbiter (MRO) for later transmission to Earth.
A warm reset is executed when the flight software identifies a problem with one of the operations it is executing which may adversely affect the rover’s operations, and is a standard fault protection mode on all automated craft operated by NASA. It resets the software to its initial state, preventing further issues occurring. While there have previously been problems with Curiosity’s on-board computers, this was actually the first time since the rover’s arrival on Mars 16 months ago that a fault-related software warm reset had been executed.
Following the reset, the rover resumed communications, but the mission team initiated a root cause analysis for the reset using the ground testbed unit (essentially, Curiosity’s Earthside “twin”). This revealed an error in a catalogue file for the existing onboard software was triggered when the catalogue file was executed by the newly uploaded flight software, causing the reset. As a result of this analysis, the flight software team were able to determine the steps required to recover the rover to its operating state prior to the reboot. These were successfully uploaded to Curiosity, and on Sunday November 10th, the rover set confirmation to mission controllers that it has successfully transitioned back to a nominal surface operations mode.
“We returned to normal engineering operations,” software and systems engineer Rajeev Joshi from the Curiosity team at JPL reported following the transition. “We are well into planning the next several days of surface operations and expect to resume our drive to Mount Sharp this week.”
Following the successful reinstatement of normal operations for the rover, the mission science team resumed planning for the next stage of Curiosity’s surface activities, which were due to restart on Thursday November 14th.
In Memory of Bruce Murray
Having joined CalTech in 1960, he was responsible for determining the geologic history of Mars based on photographs returned by the 1965 Mariner 4 fly-by mission, and employed the same technique to evaluating images returned by the later Mariner 10 orbiter mission, on which he served as chief scientist. He later took over the helm at the Jet Propulsion Laboratory, where he expressed concerns whether the science package aboard the Viking landers of the mid-1970s could achieve its stated goals. Given the later controversies surrounding the results returned by the landers, his concerns were well-founded.
In 1980, together with the late Carl Sagan and with Louis Friedman, Murray founded The Planetary Society, a global organisation of some 40,000 members, headquartered in the United States which is involved in research and engineering projects related to astronomy, planetary science, exploration, public outreach, and political advocacy.
To honour Murray’s memory, NASA Has informally christened two surface features on Mars in his name.
“Murray Ridge” is the name which has been given to an uplifted portion of the rim of Endeavour Crater, which is currently being explored by NASA’s Mars Exploration Rover Opportunity. Rising to the south of “Solander Point”, which Opportunity has been climbing and investigating for the past several weeks, “Murray Ridge” rises to an elevation of around 40 metres (130 feet) above the surrounding plain.
“Murray Ridge is the highest hill we’ve ever tried to climb with Opportunity,” said MER’s principal investigator, Steve Squyres of Cornell University, after the ridge line had been named. It has outcrops with clay minerals detected from orbit, making it a suitable target for investigation by the solar-powered rover. It also provides a favourable slope for Martian winter sunshine to hit the rover’s solar panels, an advantage for keeping Opportunity active through the Martian winter.
Located close to “Mount Sharp”, an outcrop of hillocks has been dubbed “Murray Buttes” by the MSL team. Occupying a gap in the line of sand dunes separating Curiosity from the lower slopes of “Mount Sharp”, the hillocks present a natural subject for examination by the rover once it reaches them, as it is thought that sand blown up from the dunes may act as a scouring agent on the hillocks, removing surface dust and exposing the underlying rock.
“We’ll be going right by these buttes when we shoot the gap in the dunes,” said Curiosity science-team member Ken Herkenhoff, of the U.S. Geological Survey’s Astrogeology Centre in Arizona. “It will be a visually intriguing area for both the science team and the public. I think it will look like a miniature version of Monument Valley in Utah.”
In the meantime, NADA have produced a new video narrated by MSL’s Principal Investigator, John Grotzinger, looking at Curiosity’s progress over the last 16 months.
All images courtesy of NASA / JPL, unless otherwise indicated