Last evening (June 27) between 8pm and 9pm PDT, Curiosity drove approximately 34 meters to the east to position herself just north of a large field of ripples on her way closer to ascending the iron oxide-bearing Vera Rubin Ridge. As Curiosity progresses towards the east, scientists back on Earth continue to look for opportunities to both gaze ahead towards interesting locations on the ridge itself, in addition to looking at the local rocks and sediment surrounding the rover. As we approach the lower units of Vera Rubin Ridge, our measurements of the "typical" rock that surrounds the rover will be vital to helping scientists understand how and why the ridge is different than the other units that have been investigated thus far in Gale Crater. Are we going to observe a very sharp transition in the composition and textures of rocks as we cross the threshold between the underlying mudstones of the Murray formation and the lowermost units of Vera Rubin Ridge? Or, alternatively, are we going to see a very subtle transition that might have gone unnoticed if not for the methodical measurements made upon approaching the ridge? Only time will tell, but we are making sure that we have the information necessary to definitively understand the nature of this transition.

Our science plan for the next two days begins with firing the ChemCam laser at a bedrock target right in front of Curiosity known as "Cat Sized Island". The rock is almost a meter in length (more of a bobcat size than a standard house cat) and shows some interesting nodular textures that the science team wants to investigate further. Following this measurement, two different regions of Vera Rubin Ridge itself will be imaged using the ChemCam high-resolution Remote Micro-Imager (RMI). These measurements and observations will be followed up with color images collected by Mastcam for general documentation of the ridge, "Cat Sized Island," and the ChemCam target that was automatically analyzed after yesterday's drive.

Following these measurements, Curiosity will again take to the road and head further east northeast, positioning herself towards the northernmost tip of the nearby sand ripple patch. In the next few days, the plan is to turn Curiosity towards the east southeast around these ripples and towards the ideal location to begin the climb up Vera Rubin Ridge, which is still another ~275 meters distant.

The rover team is still operating under restricted planning conditions this week, which occurs when the offset in time between Earth and Mars prohibits the team from acquiring, downlinking, and analyzing the data collected by the rover with sufficient time to generate and uplink a science plan to the rover on a daily basis. In addition, with the Fourth of July holiday early next week, today's plan includes activities for three days on the Martian surface. Following Curiosity's drive, she will acquire her standard Navcam imagery surrounding the rover to allow Friday's science planning team to have a good view of the area accessible to the rover and the instruments. ChemCam will also acquire a LIBS analysis of an automatically selected target, and will also acquire passive spectra of several calibration targets onboard the deck of the rover. Lastly, MAHLI will image a tray on the rover deck that has been collecting windblown sand to help scientists better understand the properties of these particles and how the local winds are able to move materials. Curiosity will then turn in for the evening, but will wake up around 4:30am local time to image Deimos using the Mastcam instrument. The next morning, Curiosity will resume her science activities with a series of ChemCam passive observations of calibration targets on the deck of the rover, as well as Mastcam imaging of the rover deck to check on the hardware and monitor debris cover.

On the afternoon of the second day, Curiosity will acquire additional images that have become a familiar and consistent component of the rover's scientific investigation. The fixed and immovable Mars Descent Imager, or MARDI, will acquire a suite of images looking just below the rover's belly. MARDI acquired high-resolution video at four frames per second during Curiosity's descent to the Martian surface, and while its primary objective was completed the moment Curiosity landed safely on Mars, MARDI has since been used to perform surface science. MARDI routinely collects images of the ground immediately beneath the rover to characterize the physical properties of both rocks and sediment as the rover travels through Gale Crater. Because of its consistent viewing geometry and spatial resolution of approximately one millimeter per pixel, MARDI image acquisition has become a routine and integral component to our scientific investigation of the landscapes immediately surrounding Curiosity rover as she continues her journey up Mt. Sharp.

The third and final day of this observation plan will be dominated by environmental monitoring using both the Navcam and Mastcam instruments. First, Navcam will acquire several images to hunt for dust devils in Gale Crater. Then, Mastcam will acquire images of the rim of Gale Crater to investigate the amount of dust in the Martian atmosphere. Lastly, Navcam will point nearly straight up and acquire several images over several minutes to observe any possible clouds in the sky and their movement due to atmospheric winds. These observations will be used by scientists to improve our understanding of atmospheric processes on Mars and the specific atmospheric conditions present in Gale Crater.

This past weekend, Curiosity continued to journey east along the contact between the lower portion of Vera Rubin Ridge and the Murray formation with a drive that was a little over 20 m long. Today we worked on planning two sols, Sol 1739 and Sol 1740. On the first sol, we will take MAHLI and APXS observations of a target named "Rice Point" in our continuing quest to characterize the variability of typical Murray bedrock as we ascend Mt. Sharp. We will also take some remote sensing observations to document changes in texture and chemistry of the rocks in front of us, as well as some nearby sand. We have ChemCam LIBS observations of targets named "Hamilton Pond," "Whalesback," and Rice Point. We will take associated Mastcam images to provide color documentation of the ChemCam targets, as well as Mastcam observations of "Fosters Brook" and "Skillings River." After our morning science block will we continue on our way east towards the location where we can ascend Vera Rubin Ridge. Post drive, we will take a ChemCam AEGIS observation and a special stowed MAHLI observation looking back towards Aeolis Palus to document the landscape of we've traversed across. On the second sol of the plan, we will take some Navcam observations to characterize properties of the atmosphere and to search for dust devils.

All of the data from our second imaging stop back on Sol 1734 finished coming down over the weekend, and they continue to show spectacular views of vertical bedrock exposures. We are analyzing these images to understand the nature of the geologic contact between Vera Rubin Ridge and the Murray formation, as well as the environments that deposited the layers that make up the lower ridge. We have been utilizing several of Curiosity's cameras to help with this imaging campaign. We took untargeted, post-drive Mastcam left eye images the sol before the main imaging sol to get a good context and to help us refine pointing for the Mastcam right eye images, which have higher spatial resolution but smaller fields of view. We also took pictures of select sections of the area with the ChemCam Remote Micro-Imager (RMI) that have even higher spatial resolution than the Mastcam right images, but which are black and white only. The science team will use all of these data to perform our analyses.

Ridge images from Mastcam left eye >>

Ridge images from Mastcam right eye >>

From ChemCam RMI >>

Curiosity has presented us with another beautiful workspace following a 16.6 meter drive. The majority of this week's activities were focused on imaging Vera Rubin Ridge to observe its stratigraphic and structural relationship to the underlying Murray formation. This weekend's plan is a bit of a deviation from that, as we will be making numerous measurements of the local Murray formation. These "local" observations will be extremely valuable over the coming weeks, as Curiosity potentially transitions between two different geologic units (the Murray formation and Vera Rubin Ridge). The nature of this transition will hold important clues into the origin of the ridge and the evolution of Gale Crater as a whole.

Curiosity will first use ChemCam to probe the composition of three rocky targets, followed by acquiring high-resolution Mastcam images to document the targets. The first target, known as "Winter Harbor," is situated in front of the rover. This target is a benign, flat, and finely layered piece of the Murray formation. Next, ChemCam will target "Beaver Dam Pond," which appears to be a block of the Murray formation that may have been tilted on its side. Curiosity will then point her mast just off her back right wheel, where ChemCam will investigate "Kitteredge Brook," which is a more plate-like and fractured block that appears to have a vein running through it. Lastly, Mastcam will image one additional block of typical layered rock of the Murray formation known as "Crippens Brook." The exposed layering of this target will help determine whether this section of the Murray formation is similar or different than previously analyzed locations.

After these remote observations, Curiosity will untuck her arm and engage in contact science with the "Winter Harbor" target. First, the Dust Removal Tool will be used to brush away any surface dust. Curiosity will then deploy APXS to the target, which uses the decay of the radioactive element curium to generate alpha particles and X-rays that interact with the surface material. The energy recorded coming from the surface material as a result of these interactions holds important clues into the chemistry of the surface materials. Curiosity will leave the APXS instrument in contact with "Winter Harbor" overnight to integrate its signal and to derive a precise measurement of the material's composition.

The next sol, Curiosity will investigate the chemistry of one more target ("Blunts Point," a wavy and fractured block) using ChemCam, take two contextual Mastcam images of this target, and take an additional three Mastcam images of a separate block slightly closer to the rover known as "Blunts Pond," which appears similar in texture to "Blunts Point." Mastcam will then acquire a full multispectral image of "Winter Harbor" before departing this location to the east.

Curiosity will also take multiple environmental observations in this plan. On Sol 1738, a morning imaging suite will be taken, which will include two Navcam cloud movies - a zenith movie looking directly above the rover and a supra-horizon movie looking towards the rim of Gale Crater. Mastcam will capture tau and LOS measurements to assess the amount of dust in the atmosphere. Later on Sol 1738, Mastcam will repeat the tau and LOS pair twice to determine diurnal variability in the atmospheric opacity. The plan will also include MAHLI imaging of the REMS UV sensor to determine the amount of dust on the UV photodiodes, which is done approximately every 60 sols (for more on this periodic activity, see Sol 1674). REMS and DAN measurements will be taken according to the usual cadence.

Curiosity will be an astronomer again in this plan as Mastcam will take images of both of Mars's moons, Phobos and Deimos. Deimos imaging will assist in more accurately defining the moon's orbit, so is not constrained in timing during the night. The imaging of Phobos will capture its ingress into the shadow of Mars - a Martian lunar eclipse. This specific astronomical event occurs repeatedly at this time of year, but the timing of the imaging must be exact. Imaging before the eclipse begins and during the ingress allows for an estimation of the size and amount of dust in the upper atmosphere of Mars. This is possible because as eclipse begins, the light that is reflected off of Phobos must skim through the top of Mars's atmosphere first. This light can then be compared to imaging before eclipse begins. Repeating the Phobos observation at different times of year allows for probing of the atmosphere over different locations and at different altitudes due to the relative geometry changing.

Extra link to image of previous Phobos eclipse ingress on Sol 964 >>

Curiosity continues to drive to the east-northeast around two small patches of dunes that are positioned just north of Vera Rubin Ridge. Once beyond this easternmost dune patch, the plan is for her to turn to the southeast and towards the location identified as the safest place for Curiosity to ascend the ridge. Currently, this ridge ascent point is approximately 370 meters away, which is less than the exterior length of Wembley Stadium in London. If only the path ahead were as smooth as a soccer pitch!

After a ~15 meter drive, Curiosity is situated in front of several small patches of rock about the size of large textbooks. This front Hazard Avoidance Camera (Hazcam) image shows today's view, with Mt. Sharp in the background and a portion of Vera Rubin Ridge in the upper-right corner. One of these rocks, a target known as "Pecks Point" exhibits some interesting variations in brightness, and so its chemistry will be analyzed using the APXS and ChemCam instruments, and it will be imaged using both MAHLI and Mastcam. The remainder of the science for this plan is focused on gazing longingly towards Vera Rubin Ridge. From this vantage point, we will be acquiring imagery of the northern exposure of the ridge (named "Northern Neck") using several techniques. First, we will use the multispectral capabilities of Mastcam (see below for more details) to investigate any possible compositional variations observed within this lower ridge material. Next, we will take a series of overlapping high-resolution images using ChemCam's remote microimager. Although these images won't cover the entirety of the exposure, they will allow scientists to interrogate the fine-scale sedimentary structures present within the ridge. Lastly, we will again turn to Mastcam to image the entirety of "Northern Neck" in true-color, similar to how your eyes would perceive the ridge if you were standing on the surface.

After this science imaging, Curiosity will again take off driving towards the east-northeast. The following day, Curiosity will image the rover deck using Mastcam, hunt for dust devils using the navigation cameras, and acquire additional chemistry data of local targets using ChemCam's automated target selection software known as AEGIS. The science and engineering teams will again reconvene on Friday to formulate the weekend's science plan.

I want to provide a little more context regarding the multispectral imaging capabilities of Mastcam. The cones in a human eye are sensitive to blue, green, and red wavelengths of light which, combined, allow us to see the full range of visible colors. Using a series of filters, Mastcam is able to finely control the wavelengths of light that enter the camera. This means that we can accurately calibrate the data to quantify how surfaces reflect specific wavelengths of light. In addition, Mastcam can record wavelengths beyond the sensitivity of the human eye in the near-infrared, and this additional information can be used to further investigate the composition of the martian surface. Just like how table salt is white and garnets are red, other geologic materials exhibit unique signatures in the infrared as well. As a result, Mastcam is an extremely useful geologic tool onboard Curiosity, as it allows us to investigate differences in the composition of distant surfaces.

One of the key compositional properties of Vera Rubin Ridge is the presence of the iron oxide phase hematite, as determined from orbital observations. Iron oxides are the primary constituents of rust on Earth, which can exhibit spectacular variations in color, and so identifying and characterizing minor color variations throughout the ridge will be important as the mission continues towards the ridge. What is the lateral and vertical distribution of these unique iron oxide phases? Do they vary significantly over the rover's traverse? These questions (and many more) will continue to be the focus of the MSL science team for months to come!

As this is my first time contributing to the MSL blog, I'd like to quickly introduce myself to you all. I'm Mark, an MSL Participating Scientist and a faculty member at Northern Arizona University, trained in geochemistry, spectroscopy, and remote sensing. I'm excited to help walk you all through the daily endeavors of this wonderful rover and mission!

Curiosity continues to make progress along its planned ascent route up Mt. Sharp, and is quickly approaching the hematite-bearing Vera Rubin Ridge. As a refresher, Vera Rubin Ridge is a high-standing unit that runs parallel to and along the eastern side of the Bagnold Dunes. From orbit, Vera Rubin Ridge has been shown to exhibit signatures of hematite, an oxidized iron phase whose presence can help us to better understand the environmental conditions present when this mineral assemblage formed.

Over the weekend, Curiosity drove approximately 32 meters and parked in front of a large rocky slab (about the size of a large dining room table) with smaller rocky patches nearby, perfect for our continued documentation of the local bedrock. This slab will be extensively imaged using Mastcam. In addition to imaging, three rocky targets will be chemically analyzed by the rover. "Pierce Head" represents an unremarkable piece of the Murray formation, and will be investigated using ChemCam and APXS (and MAHLI context imaging) to fully characterize the bedrock chemistry at this location. Alternatively, "Mosely Point" and "Leland Point" appear darker in tone and exhibit slightly rougher and smoother textures, respectively, and will be investigated using only ChemCam.

Following these analyses, Curiosity will set off on another drive over rough terrain to the east, where the rover will document its surroundings using its automated ChemCam targeting capabilities and its suite of cameras. In particular, the rover will turn its cameras to Vera Rubin Ridge for another suite of high resolution color images, which will help to characterize any observed layers, fractures, or geologic contacts. These observations will help the science team to determine how Vera Rubin Ridge formed and its relationship to the other geologic units found within Gale Crater.

Another super interesting observation that will be made during this planning period is an opportunistic nighttime astronomical observation of Mars' smallest moon Deimos, which will be imaged using Mastcam. Even though Deimos is only ~8 miles in diameter, Mastcam's incredible resolution and pointing capabilities make these observations seem routine. Imaging Mars' moons allows scientists to better understand the evolution of their orbits over time.

We are currently in a phase of "restricted planning," where the offset in time between the Earth and Mars prohibits our ability to downlink data with sufficient time to plan on a daily basis. So, the science and engineering teams planned two days' worth of rover activities today. We will reconvene on Wednesday to produce a similar two-day plan, and will do so through next week. Despite this offset, the crafty and efficient science and engineering teams are able to successfully create rover plans that ensure Curiosity is busy as it continues its journey up Mt. Sharp.

The drive on Sol 1728 was successful, and our weekend plan will be chock-full of activities. On the first sol, we will do some contact science on the rather colorful workspace that is currently in front of the rover. We will be collecting MAHLI and APXS observations of two targets, "Frazer Creek" and "Lurvey Spring." We will also collect some ChemCam observations of "Mark Island" and Frazer Creek plus the corresponding Mastcam documentation images of these targets. Finally, we will take a full multispectral filter Mastcam observation of Mark Island, as well as additional Mastcam images of targets "Big Spencer Mountain" and "Monument Cove."

Curiosity will wake up around 3 in the morning between the first and second sols of the plan to make a special observation of Mars' moon Phobos. We are going to watch Phobos as it emerges from Mars' shadow into sunlight. This will help us measure the amount and size of dust particles in Mars' upper atmosphere. After the sun rises on the second sol of the weekend plan, we'll do full MAHLI wheel imaging (or FMWI in rover-acronym speak). We take images of our wheels using MAHLI throughout a full wheel rotation every few hundred meters to track the rate of wheel damage.

On the third sol of the plan, we will drive and have a post-drive ChemCam AEGIS observation and dust devil search. The drive will place us ~35 meters closer to the second Vera Rubin Ridge approach-imaging stop. The data Curiosity collected during the first imaging stop earlier in the week have been coming down over the last few days, and they look absolutely spectacular. For example, a portion of the ChemCam RMI mosaic we took of the lower most layers of the ridge show a lot of fine-scale layers. I mapped Vera Rubin Ridge using orbital data as part of my PhD thesis five years ago, so it's been so exciting for me to see these images after staring at the area from above for so long. The fine scale details that we'll be able to collect using Curiosity's instruments will help us understand how Vera Rubin Ridge formed, and any implications for past habitable environments at Gale Crater.

After a busy day of contact science yesterday, today's plan was dedicated towards remote science and driving. As Mastcam PUL-1 today, I was fairly busy helping put together a suite of Mastcam images for Curiosity to take. These included mosaics of "Preble Cove" and "Fernald Point", some nice blocks of the Murray formation just in front of the rover (Fernald Point is the block just in front of the rover wheel in the Navcam image above). We'll then take a few images of "Freeman Ridge" to follow up on yesterday's multispectral observation.

We also planned a series of environmental observations, including our standard REMS and DAN, as well as a ChemCam passive sky, Mastcam tau, and line-of-sight extinction. We'll then continue driving towards Vera Rubin Ridge and take some post-drive images to set ourselves up for an exciting weekend of more remote and contact science!

After a successful drive, our parking spot included a nice patch of Murray bedrock to allow us to perform contact science (MAHLI and APXS) in today's plan. Our target for contact science is "Jones Marsh," a dark patch of the Murray that you can see just above the rightmost corner of Curiosity's mast shadow in the Navcam image. The GEO group also planned a suite of observations of Vera Rubin Ridge (VRR), which we're making great progress towards. Mastcam will perform a multispectral observation on "Freeman Ridge," a small butte just in front of VRR that shows interesting color variations. ChemCam will then take a mosaic of VRR using its Remote Micro-Imager (RMI) to complement the Mastcam mosaic we took in yesterday's plan. We will take an additional Mastcam mosaic of "Spaulding Mountain," an area of exposed Murray formation blocks along our drive path.

We will then complete a drive, do some post-drive imaging of our new location, and finish up today's plan with some environmental observations. These include tau, line-of-sight extinction, and sky survey measurements with Mastcam to assess how much dust is in the atmosphere. We will also perform our standard REMS and DAN activities.

Today I served as a PUL-1 for Mastcam. With VRR on the horizon and the fantastic Murray formation underneath our wheels, there is never a shortage of things to image!

After great anticipation over the last few weeks, the drive in the current plan will bring us into position for stop 1 of our close look at the northern face of the hematite-bearing Vera Rubin Ridge. Mastcam will take a wide mosaic to begin documenting the sedimentary structure of the ridge. GEO will take several observations of nearby targets before the drive. ChemCam will target "Mount Abraham" (bedrock on the top left in the above Navcam image) and "Mount Redington" (bedrock at top center), both of which are typical members of the Murray bedrock. Mastcam will image each of those targets as well, along with the target "Marsh Head," an area of exposed stratigraphy. GEO activities finish with Navcam documentation of our new position and MARDI imaging.

I was the ENV STL for this plan, and only one ENV cadence observation will be obtained. A 4-frame Navcam dust devil survey will be taken around noon to continue to document vortex activity as we climb Mt. Sharp. REMS will capture the usual top of the hour 5 minute observations, along with 9 hours of extended observations. DAN will take a 20 minute post-drive observation and just under 5 hours of passive observations.

On most weekends, Curiosity dedicates part of her efforts to do contact science - deployment of APXS, MAHLI, and sometimes the DRT - because multi-sol weekend plans have more time and power to fit in these more complex activities. Last weekend, however, time and power were dedicated to a more rare, and more complex, activity - analysis of a previously-drilled rock sample by SAM. To keep up our regular cadence of contact science, the team effectively extended the weekend by a day, planning contact science in this Monday plan. The workspace in front of the rover did not disappoint, with no shortage of options on a nice slab of Murray formation bedrock to reach out and touch!

The team selected a trifecta of targets for MAHLI and APXS, each with its own unique characteristic. "Haynes Point" is located on red-toned Murray, "John Small Cove" is located on tan-toned Murray, and "Barr Hill" is located on flat-lying white vein material coating parts of the workspace bedrock. The mast instruments also got in on the action, with ChemCam shooting both Haynes Point and Barr Hill, and Mastcam acquiring a multispectral observation that covered all three contact science targets. Planning such complementary observations with multiple instruments helps the team extend their understanding of the rocks interrogated by the rover. After starting off Sol 1725 with an early morning suite of environmental observations, only a few additional sky observations were acquired in the rest of the plan along with regular REMS and RAD measurements. Curiosity will get back on the road tomorrow, driving ever closer to the spectacular topography of the Vera Rubin Ridge.