A spoonful of sand, a question over plastic and an unexpected finding

Not long after I Pressed my last MSL update, Curiosity went ahead and collected its first scoop of Martian sand.

The operation took place over the course of several hours on October 7th (Sol 61), gathered a scoopful of sand and powdery material from the sand ridge the rover had been examining at a location mission managers have dubbed “Rocknest”.

The operation was the first phase in a process which is designed to “clean” the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA) device mounted on the turret at the end of Curiosity’s robot arm (and which includes the scoop itself). The cleaning process is required to ensure that no contaminants from Earth remain in CHIMRA’s chambers so they do not adversely affect analysis when samples eventually reach the on-board SAM and CheMin instruments.

A Hazcam’s view: Curiosity scoops its first load of Martian surface material

The entire process was carefully monitored using several of Curiosity’s camera systems in order to confirm progress and to make sure everything was operating as expected. This made the gathering of the first scoop of material a protracted affair, with the Hazcams at the front of the rover being used to monitor progress from a low angle and both the Navcam and Mastcam systems imaging progress and results. Once the sample has been gathered, the turret was vibrated gently to level the material in the scoop and shake-off any excess.

A Mastcam image of the scoop filled with material and (arrowed) the FOD – Foreign Object Debris – which halted scoop operations. For scale purposes, the scoop is 7 cm (2.8 inches) long, and 4.5 cm (1.8 inches) wide

It was an image from the Mastcam which brought a halt to operations, when a small, bright object was spotted. Believing the object might be something from the rover, mission managers decided to suspend the scoop operations and use the Remote Micro-Imager of the Chemistry and Camera (ChemCam) instrument to study the object in an attempt to ascertain what it might be.

This took place on Sol 62, with the assessment being that bright object appeared to be a shred of plastic material, likely benign, which had fallen from the rover, although initial examination did not definitively identify it as such. As a result, the team opted for a further day examining the object and to use the Mastcam to survey the local area for any sign of similar debris. Throughout this period, the gathered surface sample remained in the scoop.

The additional studies of the object led the team to believe it to be some type of plastic wrapper material, such as a tube used around a wire, which may have possibly fallen onto the rover from the Descent Stage during the landing in August, and which was subsequently dislodged onto the Martian surface as a result of the scoop operations.

While this analysis of the FOD – Foreign Object Debris – continued during Sol 63, operations with the Rover Environmental Monitoring Station (REMS) were extended to gather further data while in the Rocknest location, and the Mastcam system was updated with instructions to take a panoramic sweep of the area early on Sol 64, ahead of the upload of that day’s mission instructions.

Two further views of the first scoop operation performed by Curiosity on Sol 61, captured by the Mastcam system

Sol 64 saw cleaning operations resume, with the gathered sample being transferred into CHIMRA and vibration operations started in order to use the material to scrub the insides of CHIMRA’s chambers clean of any remaining Earth-based deposits. The process lasted several hours and involved rotating the turret a number of times to ensure the surfaces within CHIMRA were all scrubbed, after which the material was deposited back onto the Martian surface. While this work continued, the Mastcam captured images of rocks and other features in the immediate vicinity of the rover, having earlier completed taking a panoramic look of the region as a whole.

One of the Mastcam iamges which will be used to create a further panoramic view of Gale Crater. This is a raw image, without compensatory white balance, showing how Mars actually looks under local early morning lighting conditions.

On Sol 65 (October 11th) Curiosity completed several activities in preparation for collecting its second scoop of  Martian soil from the sand ripple at Rocknest. As with the first, this will be used for cleaning purposes. The preliminary work included close-up images of a potential sample using the Mars Hand Lens Imager (MAHLI). After this second scoop operation has been completed, samples are liable to be collected for delivery to the on-board observation tray and to CheMin.

Jake Matijevic: As Extraordinary as its Namesake

On September 22nd, Curiosity examined what was thought to be an “unremarkable” rock found while en route to Glenelg. Dubbed “Jake Matijevic”, or “Jake”, in memory of NASA / JPL engineer Jacob Matijevic, who worked on all three generations of NASA’s Mars rovers and who passed away shortly after Curiosity arrived in Gale Crater, the rock was initially believed to be quite ordinary.

However, analysing the results of Curiosity’s studies, the science team were surprised to discover it to be a close match in chemical composition to an unusual but well-known type of igneous rock found in many volcanic provinces on Earth. The data used by the team came from both the Alpha Particle X-Ray Spectrometer (APXS) mounted on the rover’s turret and from the laser / telescope systems of the mast-mounted ChemCam system.

“Jake is kind of an odd Martian rock,” said APXS Principal Investigator Ralf Gellert of the University of Guelph in Ontario, Canada, commenting on the results. “It’s high in elements consistent with the mineral feldspar, and low in magnesium and iron.”

Edward Stolper, the mission co-investigator from the California Institute of Technology, Pasadena, described rocks with similar chemical composition as being, “Widespread on Earth, on oceanic islands such as Hawaii, and St Helena, and the Azores; and also in rift zones like the Rio Grande and so forth. So, again, it’s not common, but it’s very well-known.”

Jake Matijevic – the markings show where ChemCam and APXS were used to examine it

It is the first time a rock with this kind of composition has been found on Mars, and while the planet was once volcanically active, it unknown if Jake is the result of similar volcanic actions which give rise to its Earthly cousins, “But it is a reasonable place to start thinking about its origin,” Stolper said.

Investigators were first drawn to the rock due to its unusual shape, marking it as a means of calibrating APXS. The studies carried out also marked the first time APXS and ChemCam were used together.

The Mission Summary Video

And in Space, A Dragon Returns to the ISS

This week also saw the successful launch of the first non-demonstration mission for the SpaceX Dragon craft, which many from SL and the metaverse again watched and shared through Twitter. Launched on October 7th, on the first official resupply mission to the International Space Station (a previous launch and rendezvous, although carrying materials for the station and its crew, was still a mission capabilities demonstration). The vehicle arrived in close proximity to the ISS on October 10th, and was successfully grappled by Akihiko Hoshide of the Japan Aerospace Exploration Agency, using the space station’s robotic arm, before ISS Expedition 33 commander Sunita Williams manoeuvred the spacecraft to dock it with the station’s Harmony module.

Dragon CRS-1 berthed against the International Space Station

A belated congratulations to all at SpaceX and NASA.

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