Detective work enables Perseverance Mars rover team to revive SHERLOC instrument

After six months of effort, an instrument that helps the Mars rover search for potential indicators of historical microbial life has come again on-line.

The SHERLOC (Scanning Liveable Environments with Raman & Luminescence for Organics and Chemical substances) instrument aboard NASA’s Perseverance Mars rover has analyzed a rock goal with its spectrometer and digital camera for the primary time since encountering a problem this previous January. The instrument performs a key position within the mission’s seek for indicators of historical microbial life on Mars. Engineers at NASA’s Jet Propulsion Laboratory in Southern California confirmed on June 17 that the instrument succeeded in accumulating knowledge.

“Six months of working diagnostics, testing, imagery and knowledge evaluation, troubleshooting, and retesting could not include a greater conclusion,” stated SHERLOC principal investigator Kevin Hand of JPL.

Mounted on the rover’s robotic arm, SHERLOC makes use of two cameras and a laser spectrometer to seek for organic compounds and minerals in rocks which were altered in watery environments and will reveal indicators of previous microbial life. On Jan. 6, a movable lens cowl designed to guard the instrument’s spectrometer and one in every of its cameras from dust grew to become frozen able that prevented SHERLOC from accumulating knowledge.

Evaluation by the SHERLOC workforce pointed to the malfunction of a small motor accountable for transferring the protecting lens cowl in addition to adjusting the main target for the spectrometer and the Autofocus and Context Imager (ACI) digital camera. By testing potential options on a replica SHERLOC instrument at JPL, the workforce started a protracted, meticulous analysis course of to see whether or not and the way the lens cowl is likely to be moved into the open place.

SHERLOC sleuthing

Amongst many different steps taken, the workforce tried heating the lens cowl’s small motor, commanding the rover’s robotic arm to rotate the SHERLOC instrument below completely different orientations with supporting Mastcam-Z imagery, rocking the mechanism backwards and forwards to loosen any particles probably jamming the lens cowl, and even partaking the rover’s percussive drill to attempt jostling it unfastened. On March 3, imagery returned from Perseverance confirmed that the ACI cowl had opened greater than 180 levels, clearing the imager’s subject of view and enabling the ACI to be positioned close to its goal.

“With the duvet out of the way in which, a line of sight for the spectrometer and digital camera was established. We have been midway there,” stated Kyle Uckert, SHERLOC deputy principal investigator at JPL. “We nonetheless wanted a method to focus the instrument on a goal. With out focus, SHERLOC photos could be blurry and the spectral sign could be weak.”

Like several good ophthalmologist, the workforce set about determining SHERLOC’s prescription. Since they could not regulate the main target of the instrument’s optics, they relied on the rover’s robotic arm to make minute changes within the distance between SHERLOC and its goal as a way to get the very best picture decision. SHERLOC was commanded to take photos of its calibration goal in order that the workforce might examine the effectiveness of this strategy.

“The rover’s robotic arm is superb. It may be commanded in small, quarter-millimeter steps to assist us consider SHERLOC’s new focus place, and it will possibly place SHERLOC with excessive accuracy on a goal,” stated Uckert. “After testing first on Earth after which on Mars, we found out the very best distance for the robotic arm to position SHERLOC is about 40 millimeters,” or 1.58 inches. “At that distance, the info we acquire ought to be pretty much as good as ever.”

Affirmation of that high-quality positioning of the ACI on a Martian rock goal got here down on Might 20. The verification on June 17 that the spectrometer was additionally purposeful checked the workforce’s final field, confirming that SHERLOC is operational.

“Mars is difficult, and bringing devices again from the brink is even more durable,” stated Perseverance venture supervisor Artwork Thompson of JPL. “However the workforce by no means gave up. With SHERLOC again on-line, we’re persevering with our explorations and pattern assortment with a full complement of science devices.”

Perseverance is within the later phases of its fourth science marketing campaign, searching for proof of carbonate and olivine deposits within the “Margin Unit,” an space alongside the within of Jezero Crater’s rim. On Earth, carbonates usually kind within the shallows of freshwater or alkaline lakes. It’s hypothesized that this additionally is likely to be the case for the Margin Unit, which shaped over 3 billion years in the past.