Slope monitoring. The recurring slope lineae (RSL) in this image are large and have high contrast. Most importantly, we see multiple examples of RSL flowing on bedrock, alternating between bedrock and regolith and bedrock and regolith, and regolith only. Do these candidate RSL fade? Do only the regolith RSL fade? Do they all lengthen?
HiRISE Picture of the Day archive. [More at links]
This may look like a collection of colourful contact lenses and in some respects there are some similarities: these are the filters through which the ExoMars rover – Rosalind Franklin – will view Mars in visible and near infrared wavelengths.
They are pictured here in their individual transport cases, before they were installed in the filter wheels of the Panoramic Camera, PanCam, which comprises two wide-angle cameras and a high-resolution camera. The wide-angle cameras are mounted at each end of the PanCam unit and form a stereo pair. Each camera has a filter wheel with 11 positions. Red, green and blue broadband imaging filters for colour stereo imaging are common to both left and right cameras; the remaining eight are different between left and right to provide the range of filters needed for geological and solar imaging. The geology filters have been specifically selected to identify water-rich minerals and clays on Mars… [More at link]
THEMIS Image of the Day, May 27, 2019. This false-color image shows part of Mangala Fossa – the linear depression in the bottom half of the image.
The bright blue tones in this image are thought to be surface frost. It is winter time and early in the morning when this image was taken.
The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. These false color images may reveal subtle variations of the surface not easily identified in a single band image.
Explore more THEMIS Images of the Day by geological subject.
Sols 2416-18, May 24, 2019, update by MSL scientist Catherine O’Connell-Cooper: At the start of today’s planning, the Geology theme group (GEO) had a major decision to make, whether to drill here at “Broad Cairn” or not. Unfortunately, APXS data indicated that this rock lies just outside of our desired compositional parameters, with lower potassium (K) than we would have liked. This made for a hectic start to planning as we discussed the implications of these results and decided not to drill after all, moving instead to Plan B. We will use this three-sol plan to finish investigating the chemical variability here and then begin the drive back to start a reinvestigation of an earlier target from sol 2359, “Woodland Bay,” around 130 metres away. This is a very interesting laminated rock, with alternating thinner and thicker layers, and it is possible that one of these layers is the source of the pebbles we see strewn about Glen Torridon. [More at link]
Science fiction stories are chock full of terraforming schemes and oxygen generators for a very good reason—we humans need molecular oxygen (O2) to breathe, and space is essentially devoid of it. Even on other planets with thick atmospheres, O2 is hard to come by.
So, when we explore space, we need to bring our own oxygen supply. That is not ideal because a lot of energy is needed to hoist things into space atop a rocket, and once the supply runs out, it is gone.
One place molecular oxygen does appear outside of Earth is in the wisps of gas streaming off comets. The source of that oxygen remained a mystery until two years ago when Konstantinos P. Giapis, a professor of chemical engineering at Caltech, and his postdoctoral fellow Yunxi Yao, proposed the existence of a new chemical process that could account for its production. Giapis, along with Tom Miller, professor of chemistry, have now demonstrated a new reaction for generating oxygen that Giapis says could help humans explore the universe and perhaps even fight climate change at home. More fundamentally though, he says the reaction represents a new kind of chemistry discovered by studying comets.
[The team’s findings, titled “Direct dioxygen evolution in collisions of carbon dioxide with surfaces,” appear in the May 24 issue of Nature Communications; more at links]
Wind has shaped the face of Mars for millennia, but its exact role in piling up sand dunes, carving out rocky escarpments or filling impact craters has eluded scientists until now.
In the most detailed analysis of how sands move around on Mars, a team of planetary scientists led by Matthew Chojnacki at the University of Arizona Lunar and Planetary Lab set out to uncover the conditions that govern sand movement on Mars and how they differ from those on Earth.
The results, published in the current issue of the journal Geology, reveal that processes not involved in controlling sand movement on Earth play major roles on Mars, especially large-scale features on the landscape and differences in landform surface temperature.
“Because there are large sand dunes found in distinct regions of Mars, those are good places to look for changes,” said Chojnacki, associate staff scientist at the UA and lead author of the paper, “Boundary conditions controls on the high-sand-flux regions of Mars.” “If you don’t have sand moving around, that means the surface is just sitting there, getting bombarded by ultraviolet and gamma radiation that would destroy complex molecules and any ancient Martian biosignatures.” [More at links]
On a test flight in Death Valley, California, an Airbus helicopter carried an engineering model of the Lander Vision System (LVS) that will help guide NASA’s next Mars mission to a safe touchdown on the Red Planet. During the flight – one in a series — the helicopter (which is not part of the mission and was used just for testing) and its two-person crew flew a pre-planned sequence of maneuvers while LVS collected and analyzed imagery of the barren, mountainous terrain below.
LVS is an integral part of a guidance system called Terrain-Relative Navigation (TRN) that will steer NASA’s Mars 2020 rover away from hazardous areas during its final descent to Jezero Crater on Feb. 18, 2021.
Mars 2020 will be the first spacecraft in the history of planetary exploration with the ability to accurately retarget its point of touchdown during the landing sequence. Also among the firsts of the mission, the 2020 rover carries a sample-caching system that will collect samples of Martian rock and soil and store them on the surface of the planet for retrieval and return to Earth by subsequent missions. [More at link]
[Editor’s note: From a paper by Jonathan Bapst and three co-authors recently published in the Journal of Geophysical Research.]
• We identify residual water ice with elevated surface porosity (>40%) that is densified at depths <0.5 m, consistent with recent accumulation
• Denser, vertically homogeneous ice is detected at the residual cap edge, consistent with ablation and exhumation of older, densified ice
The polar regions of Mars host kilometer‐thick stacks of water ice that have been built up over millions of years. At the north pole today, the top of this ice deposit is interacting with the Martian atmosphere. Whether or not ice at the surface is fluffy (like snow) or dense (like an ice slab) can provide useful information about the polar ice cap and recent climate.
Multiple years of surface temperature measurements have been acquired by instruments aboard spacecraft in orbit around Mars. By comparing these values with temperature simulations, we can narrow down the type of ice near the surface.
Our results show that the type of ice varies across the polar cap. Some regions appear to be a snow‐like surface where the polar cap may be growing. Other regions, most notably along the edge of the polar cap, show denser ice that is likely older. The nature of the ice tells us about the current climate and how these kilometer‐thick ice deposits form. [More at link]
In the land of Terra Sabaea. The rationale for this observation is to look at the fluvial features and diverse composition of the terrain. Terra Sabaea is fairly large and parts of it are found in five quadrangle regions of Mars, reaching 4,700 kilometers at its greatest extent.
HiRISE Picture of the Day archive. [More at links]
NASA’s Mars 2020 spacecraft has completed acoustic and thermal vacuum (TVAC) testing at the Jet Propulsion Laboratory in Pasadena, California. The acoustic test of the spacecraft that will carry the Mars 2020 rover to a soft touchdown in Jezero Crater on Feb. 18, 2021, is the best Earthly approximation for what the spacecraft will endure during launch, where it will encounter potentially destructive levels of sound and vibration. TVAC introduces the vacuum and extreme temperatures of space that could cause components to malfunction or fail.
“First we blast it with sound to make sure nothing vibrates loose,” said David Gruel, the Mars 2020 assembly, test and launch operations manager at JPL. “Then, after a thorough examination, we ‘put it in space’ by placing the spacecraft in this huge vacuum chamber we have here at JPL. We pump out the atmosphere, then chill parts of it and cook others while testing the performance of the entire spacecraft.” [More at link]
