Category Archives: Mars Rovers

Sand Dunes on Mars

It has been a while since I’ve done a Curiosity rover update. Curiosity continues to do great science on Mars, although the wheels are showing more wear and hopefully design modifications are in place for the next rover. Still, Curiosity can get around and with judicious planning it will continue to do so in the future.

The image shows there is wind on Mars and that helps keep Curiosity clean enough to provide power for operations and the wind is strong enough to make ripples in the landscape. One would imagine the texture is very fine because the wind is blowing in a thin atmosphere. The primarily Carbon Dioxide atmosphere (95.6 %) on Mars has a pressure only around 0.6 percent of what we see here on Earth.

NASA – This view from the Mast Camera (Mastcam) on NASA’s Curiosity Mars rover shows two scales of ripples, plus other textures, in an area where the mission examined a linear-shaped dune in the Bagnold dune field on lower Mount Sharp.

The scene is an excerpt from a 360-degree panorama acquired on March 24 and March 25, 2017, (PST) during the 1,647th Martian day, or sol, of Curiosity’s work on Mars, at a location called “Ogunquit Beach.”

Crests of the longer ripples visible in the dark sand of the dune are several feet (a few meters) apart. This medium-scale feature in active sand dunes on Mars was one of Curiosity’s findings at the crescent-shaped dunes that the rover examined in late 2015 and early 2016. Ripples that scale are not seen on Earth’s sand dunes. Overlaid on those ripples are much smaller ripples, with crests about ten times closer together.

Textures of the local bedrock in the foreground — part of the Murray formation that originated as lakebed sediments — and of gravel-covered ground (at right) are also visible. The image has been white-balanced so that the colors of the colors of the rock and sand materials resemble how they would appear under daytime lighting conditions on Earth.

Image: NASA/JPL-Caltech/MSSS

Kick Those Tires

We have been following the wheel wear on the Curiosity rover for a few years now.

NASA of course noticed and have been keeping an eye on the wheels with regular inspections.  New breaks in the tread have been found.

Credits: NASA/JPL-Caltech/MSSS

Here’s the latest status report from NASA:

A routine check of the aluminum wheels on NASA’s Curiosity Mars rover has found two small breaks on the rover’s left middle wheel—the latest sign of wear and tear as the rover continues its journey, now approaching the 10-mile (16 kilometer) mark.

The mission’s first and second breaks in raised treads, called grousers, appeared in a March 19 image check of the wheels, documenting that these breaks occurred after the last check, on Jan. 27.

“All six wheels have more than enough working lifespan remaining to get the vehicle to all destinations planned for the mission,” said Curiosity Project Manager Jim Erickson at NASA’s Jet Propulsion Laboratory, Pasadena, California. “While not unexpected, this damage is the first sign that the left middle wheel is nearing a wheel-wear milestone,”

The monitoring of wheel damage on Curiosity, plus a program of wheel-longevity testing on Earth, was initiated after dents and holes in the wheels were seen to be accumulating faster than anticipated in 2013. Testing showed that at the point when three grousers on a wheel have broken, that wheel has reached about 60 percent of its useful life. Curiosity already has driven well over that fraction of the total distance needed for reaching the key regions of scientific interest on Mars’ Mount Sharp.

Curiosity Project Scientist Ashwin Vasavada, also at JPL, said, “This is an expected part of the life cycle of the wheels and at this point does not change our current science plans or diminish our chances of studying key transitions in mineralogy higher on Mount Sharp.”

Curiosity is currently examining sand dunes partway up a geological unit called the Murray formation. Planned destinations ahead include the hematite-containing “Vera Rubin Ridge,” a clay-containing geological unit above that ridge, and a sulfate-containing unit above the clay unit.

The rover is climbing to sequentially higher and younger layers of lower Mount Sharp to investigate how the region’s ancient climate changed billions of years ago. Clues about environmental conditions are recorded in the rock layers. During its first year on Mars, the mission succeeded at its main goal by finding that the region once offered environmental conditions favorable for microbial life, if Mars has ever hosted life. The conditions in long-lived ancient freshwater Martian lake environments included all of the key chemical elements needed for life as we know it, plus a chemical source of energy that is used by many microbes on Earth.

Through March 20, Curiosity has driven 9.9 miles (16.0 kilometers) since the mission’s August 2012 landing on Mars. Studying the transition to the sulfate unit, the farthest-uphill destination, will require about 3.7 miles (6 kilometers) or less of additional driving. For the past four years, rover drive planners have used enhanced methods of mapping potentially hazardous terrains to reduce the pace of damage from sharp, embedded rocks along the rover’s route.

Each of Curiosity’s six wheels is about 20 inches (50 centimeters) in diameter and 16 inches (40 centimeters) wide, milled out of solid aluminum. The wheels contact ground with a skin that’s about half as thick as a U.S. dime, except at thicker treads. The grousers are 19 zigzag-shaped treads that extend about a quarter inch (three-fourths of a centimeter) outward from the skin of each wheel. The grousers bear much of the rover’s weight and provide most of the traction and ability to traverse over uneven terrain.

JPL, a division of Caltech in Pasadena, California, manages NASA’s Mars Science Laboratory Project for NASA’s Science Mission Directorate, Washington, and built the project’s rover, Curiosity. For more information about the mission, visit:

 

 

Martian Mud Cracks?

Yet more evidence of water on Mars. Would we be able to detect any traces of life if it existed after a couple thousand-million years or so?

From NASA:

The network of cracks in this Martian rock slab called “Old Soaker” may have formed from the drying of a mud layer more than 3 billion years ago. The view spans about 4 feet (1.2 meters) left-to-right and combines three images taken by the Mars Hand Lens Imager (MAHLI) camera on the arm of NASA’s Curiosity Mars rover.

Mud cracks would be evidence of a time when dry intervals interrupted wetter periods that supported lakes in the area. Curiosity has found evidence of ancient lakes in older, lower-lying rock layers and also in younger mudstone that is above Old Soaker.

MAHLI was positioned about 3 feet (90 centimeters) above the surface when it took the component images on Dec. 31, 2016, during the 1,566th Martian day, or sol, of Curiosity’s work on Mars. This observation was planned as part of assessing a hypothesis that the target preserves evidence of drying mud. The location is within an exposure of Murray formation mudstone on lower Mount Sharp inside Gale Crater.

The slab bears a network of four- and five-sided polygons about half an inch to 1 inch (1 to 2 centimeters) across, which matches the pattern commonly formed when a thin layer of mud dries. Some edges of the polygons are ridges of material the same color as the surrounding rock. This could result from a three-step process after cracks form due to drying: Wind-blown sediments accumulate in the open cracks. Later, these sediments and the dried mud become rock under the pressure of multiple younger layers that accumulate on top of them. Most recently, after the overlying layers were eroded away by wind, the vein-filling material resists erosion better than the once-muddy material, so the pattern that began as cracks appears as ridges.

Note that some of the cracks contain material much brighter than the surrounding rock. These are mineral veins. Curiosity has found such bright veins of calcium sulfate in many rock layers the rover has investigated. These veins form from circulation of mineral-laden groundwater through underground cracks. Rover-team scientists suggest that a likely scenario for the history of Old Soaker is more than one generation of fracturing: mud cracks first, with sediment accumulating in them, then a later episode of underground fracturing and vein forming.

The target rock’s name comes from the name of an island off the coast of Maine. The names informally assigned by the rover team to features in the area of lower Mount Sharp that includes this slab are from a list of islands, hills and other sites in or near Maine’s Bar Harbor.

Malin Space Science Systems, San Diego, built and operates MAHLI. NASA’s Jet Propulsion Laboratory, a division of the Caltech in Pasadena, California, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington, and built the project’s Curiosity rover. More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/.

Credit: NASA/JPL-Caltech/MSSS

Egg Rock

eggrock2

This golf-ball-sized object, informally named “Egg Rock,” is an iron-nickel meteorite. Iron-nickel meteorites are a common class of space rocks found on Earth, and previous examples have been found on Mars, but Egg Rock is the first on Mars to be examined with a laser-firing spectrometer.

The laser pulses on Oct. 30, 2016, induced bursts of glowing gas at the target, and ChemCam’s spectrometer read the wavelengths of light from those bursts to gain information about the target’s composition. The laser pulses also burned through the dark outer surface, exposing bright interior material.

If you click the image above you will get a  colorized view from the Chemistry and Camera (ChemCam) instrument on NASA’s Curiosity Mars rover shows a grid of shiny dots where ChemCam had fired laser pulses used for determining the chemical elements in the target’s composition.

Credit: NASA/JPL-Caltech/LANL/CNES/IRAP/LPGNantes/CNRS/IAS/MSSS

Wharton Ridge

Here is an image taken of the western rim of Endeavour Crater on Mars. This image contains a portion of “Marathon Valley and “Wharton Ridge” and was taken in August 2016 by the rover Opportunity!

oppyinseptember16

From the caption released with the image:

The full extent of Wharton Ridge is visible, with the floor of Endeavour Crater beyond it and the far wall of the crater in the distant background. Near the right edge of the scene is “Lewis and Clark Gap,” through which Opportunity crossed from Marathon Valley to “Bitterroot Valley” in September 2016.

Before the rover departed Marathon Valley, its panoramic camera (Pancam) acquired the component images for this scene on Aug. 30, 2016, during the 4,480th Martian day, or sol, of Opportunity’s work on Mars.

Opportunity’s science team chose the ridge’s name to honor the memory of Robert A. Wharton (1951-2012), an astrobiologist who was a pioneer in the use of terrestrial analog environments, particularly in Antarctica, to study scientific problems connected to the habitability of Mars. Over the course of his career, he was a visiting senior scientist at NASA Headquarters, vice president for research at the Desert Research Institute, provost at Idaho State University, and president of the South Dakota School of Mines and Technology.

The view spans from east-northeast at left to southeast at right. It merges exposures taken through three of the Pancam’s color filters, centered on wavelengths of 753 nanometers (near-infrared), 535 nanometers (green) and 432 nanometers (violet). It is presented in approximately true color.

Credit: NASA/JPL-Caltech/Cornell/Arizona State Univ.

Leaving Murray Buttes

murraybuttes

The roving Mars Science Laboratory Curiosity is leaving Murray Buttes and those fabulous layered rocks. To be more accurate Murray Buttes is a region on Mount Sharp and is a great example of wind in action.

The buttes and mesas rising above the surface in this area are eroded remnants of ancient sandstone that originated when winds deposited sand after lower Mount Sharp had formed. Curiosity closely examined that layer — called the “Stimson formation” — during the first half of 2016, while crossing a feature called “Naukluft Plateau” between two exposures of the Murray formation. The layering within the sandstone is called “cross-bedding” and indicates that the sandstone was deposited by wind as migrating sand dunes.

The image was taken on Sept. 8, 2016, during the 1454th Martian day, or sol, of Curiosity’s work on Mars. — NASA

Image: NASA/JPL-Caltech/MSSS

A Look Around Curiosity

Here’s a look around Curiosity, or the Mars Science Laboratory on Mars.  For two minutes you can look around the scene by using the arrows at the top left of the video or just “clicking and dragging” your way around.  Running out of time is no problem just replay the video (or whatever you would call this).

The scene is from a location called Murray Buttes and most of the features are labeled.  The rover is not visible in this MastCam product.

For scale The dark, flat-topped mesa seen to the left of the rover’s arm is about 50 feet (about 15 meters) high and, near the top, about 200 feet (about 60 meters) wide according to NASA.

I was looking at the panorama and thought how completely quiet it must be up there and what it would sound like to try and get an echo off the buttes. The echo time lag of course depends on the speed of sound on Mars. Looking around on the web quickly reveals the speed of sound on Mars is about 244.4 m/s or 801.3 ft/s compared to 340 m/sec or 1115 ft/sec on Earth. So the echo would take nearly 25 percent longer to return on Mars than on Earth.

Video

Speed of sound on Mars
Speed of sound on Earth

Mission Extended

Four years down and now there are two more to go for the Mars Science Laboratory or Curiosity. The rover looks to be in rather good condition, the wheels are a bit worn but not seeming to be getting worse, so who knows we could have Curiosity around for quite a while.

Video

Getting Sandy

sandyselfie

 

The MSL rover Curiosity is showing it is getting sand covered, in fact there is a pretty good build up on some of the surfaces. Seems like not so long ago I commented that the dust was much less than I thought it could be.

From NASA’s website:

This self-portrait of NASA’s Curiosity Mars rover shows the vehicle at “Namib Dune,” where the rover’s activities included scuffing into the dune with a wheel and scooping samples of sand for laboratory analysis.

The scene combines 57 images taken on Jan. 19, 2016, during the 1,228th Martian day, or sol, of Curiosity’s work on Mars. The camera used for this is the Mars Hand Lens Imager (MAHLI) at the end of the rover’s robotic arm.

Namib Dune is part of the dark-sand “Bagnold Dune Field” along the northwestern flank of Mount Sharp. Images taken from orbit have shown that dunes in the Bagnold field move as much as about 3 feet (1 meter) per Earth year.

The location of Namib Dune is show on a map of Curiosity’s route at http://mars.nasa.gov/msl/multimedia/images/?ImageID=7640. The relationship of Bagnold Dune Field to the lower portion of Mount Sharp is shown in a map at http://photojournal.jpl.nasa.gov/catalog/PIA16064.)

The view does not include the rover’s arm. Wrist motions and turret rotations on the arm allowed MAHLI to acquire the mosaic’s component images. The arm was positioned out of the shot in the images, or portions of images, that were used in this mosaic. This process was used previously in acquiring and assembling Curiosity self-portraits taken at sample-collection sites, including “Rocknest” (http://photojournal.jpl.nasa.gov/catalog/PIA16468), “Windjana” (http://photojournal.jpl.nasa.gov/catalog/PIA18390) and “Buckskin” (http://photojournal.jpl.nasa.gov/catalog/PIA19807).

For scale, the rover’s wheels are 20 inches (50 centimeters) in diameter and about 16 inches (40 centimeters) wide.

MAHLI was built by Malin Space Science Systems, San Diego. NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington. JPL designed and built the project’s Curiosity rover.

More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/.

Credit: NASA/JPL-Caltech/MSSS