Tag: Mars Reconnaissance Orbiter

Click for higher resolution. Original images found here and here.

Today’s cool image to the right is a mosaic I have made from two images taken by the context camera on Mars Reconnaissance Orbiter (MRO), showing a most intriguing region on Mars dubbed Avernus Cavi, located in the large volcanic plain called Elysium Planitia between the giant volcanoes Elysium Mons and Olympus Mons, a region I like to call Mars’ volcano country.

The mosaic shows in one picture much of the typical terrain in Avernus Cavi. We see many linear depressions or cracks, created when the ground stretched and cracked at weak points. We also see many depressions that suggest sinkholes, places where the surface sagged down because of a void below ground.

The area of knobs and mesas in the picture’s southeast quadrant is very typical Martian chaos terrain, the later result of long term erosion of these cracks and depressions.

The white box shows the area covered by the image below.
» Read more

Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on May 27, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows the clash of different layers on the western slope of a mountain within Mars’ largest canyon, Valles Marineris.

The scientist have labeled this a “possible angular unconformity.” In geology an unconformity generally refers to a gap in a series of layers, a period when instead of the layers being deposited they are being eroded away, leaving no record for that time period. An angular unconformity adds tilting to the older layers, which after erosion are then covered by new layers that are oriented somewhat differently.

Based on these definitions, what the scientists suspect is that the brighter layers to the left and lower down the mountain are older. After a period of erosion new layers were deposited on top at a different angle, forming the stripe of layers going from center left up to center right.

The swirly nature of the material on the top of the ridge suggests to me that these layers might be volcanic in nature, but that’s a pure uneducated guess. What some scientists do believe (but have not yet conclusively proven) is that the lower older layers are sediments laid down by an ancient lake that once filled the canyon here.

The overview map below provides a wider view and some context.
» Read more

Cool image time! The photo to the right, rotated and cropped to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) on April 27, 2021. It shows a strange scattering of dunes on a flat plain. The red at the top of each dune probably indicates exposed dust and sand. The white fringe is likely either water frost or the leftover mantle of dry ice that is deposited in the polar regions each winter down to 60 degrees latitude, and disappears with the coming of spring, sublimating back into carbon dioxide gas.

There are a lot of puzzles here. The overview map below provides some context, but only some.
» Read more

Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, is actually a somewhat old image from the high resolution camera on Mars Reconnaissance Orbiter (MRO). It was taken more than a decade ago, on December 28, 2010, and featured as a captioned image one month later. I post it now because it was recently featured as MRO’s picture of the day, and thought it deserved a new look. As the caption from 2010, written by planetary scientist Alfred McEwen, noted,

Remember those paisley shirts during the summer of love in 1967? If so, this terrain may look somewhat familiar.

How did this terrain really form? One theory is that it’s a landslide deposit, perhaps associated with draining an ancient lake.

The overview map below might help make sense of this theory.
» Read more

Click for full image.

Cool image time! The photo to the right, rotated, cropped and reduced to post here, was taken on April 18, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a nice sample of the typical glacial-filled craters found often in the mid-latitudes between 30 to 60 degree latitudes, surrounded by a lot of erosion features representative of these lowland northern plains.

The biggest crater is very symptomatic of what scientists have dubbed concentric crater fill, a feature that they believe reveals that there is buried ice water glaciers here, protected by a thin layer of debris. The apron of brighter material surrounding the crater could be a splash feature created during impact and now more obvious because it has been revealed as sublimation and erosion lowered the terrain nearby.

The location is north of the Cydonia region in Acidalia Planitia, several thousand miles to the northeast of the region where Viking 1 landed in 1976 and Mars Pathfinder landed in 1997, as shown in the overview map below.
» Read more