lithified
May 3, 2022
May 3, 2022 I don’t typically have much time for these posts anymore. The pandemic seems to have changed everything. But sometimes I need to remind myself why I do this for a living. Going to look through Mars’ gorgeous […]
March 29, 2021
March 29, 2021 Mars is such a fun place. We’re finding out that it’s got oodles of geologic history. It’s got layers deposited by wind and water and lava, altered in place (sometimes many times), then eroded again by wind […]
June 15, 2020
June 15, 2020 Utopia Planitia is an ancient plain in the northern lowlands of Mars, thought to be made of volcanic rocks that were buried, more than 3 billion years ago, by sediments carried by water coming down from the […]
March 4, 2019
On Earth, really old windblown dunes don’t usually survive long enough to become part of the geologic rock record. Dunes are made of unconsolidated sand, which is easily eroded by just about anything, so it takes special circumstances to keep […]
August 13, 2018
Mars has been dusty, and that’s affecting the quality of HiRISE images (just look at the recent images in the catalog and you’ll see they’re not that great). That’s made it hard for me to choose a good one for […]
August 7, 2017
A Piece of Mars: The large dunes in the middle of this 375×450 m (0.23×0.28 mi) scene run along a valley (the small dunes at top and bottom are on high ground). What’s amazing about this is that the ends […]
May 22, 2017
A Piece of Mars: There are many barchans on Mars, those lovely isolated crescent-shaped dunes. In a few places there are what looks like ancient preserved barchans, now lithified. The mound in the center of this 0.96×0.54 km (0.6×0.33 mi) […]
January 30, 2017
A Piece of Mars: How do you tell when a planetary landscape shows Mars, instead of Mercury or the Moon or Europa? The easiest way to tell is to look for both craters and dunes, like what’s shown here in […]
January 3, 2017
A Piece of Mars: Mars rarely does anything without drama. Long ago in this 0.96×0.54 km (0.6×0.34 mi) scene, large ripples formed and then, presumably, lithified (turned into rock). Some time after that, an impact formed the crater in the […]