Starship Asterisk*

[quote="sillyworm2"]

What a wonderfully framed picture.I like how the salt flats have a crystal pattern on the surface.[/quote][quote=" https://en.wikipedia.org/wiki/Mud_cracks_on_Mars"]

[float=right][img3="[b][color=#0000FF]Probable mud cracks appearing as ridges, as seen by Curiosity Rover.[/color][/b]"]https://upload.wikimedia.org/wikipedia/commons/thumb/9/97/Wikimudcracksdense.jpg/1024px-Wikimudcracksdense.jpg[/img3][/float]<<In January, 2017, scientists announced the possible discovery of mud cracks in Gale Crater on Mars. The Curiosity Rover imaged what may be the first mud cracks (desiccation cracks) ever found on Mars. They may have been formed from drying mud. The site, called “Old Soaker,” was within an exposure of Murray formation mudstone on lower Mount Sharp. It is hypothesized that these cracks formed more than 3 billion years ago and then were buried by more sediment. All this material eventually turned into rock. Later wind erosion removed the layers that covered the cracked layer. The cracks were filled with material which was resistant to later erosion. This erosion resistant material formed raised ridges, as some of the surrounding layer was removed. This is the first sighting of mud cracks. Previously, Curiosity has examined cracks and ridges of different shapes that were made by groundwater carrying minerals, such as calcium sulfate. Cracks for this process were caused by the pressure of overlying sediments fracturing rock. Gale Crater held ancient lakes that varied in depth and area over time, and sometimes disappeared. Mud cracks show that there were dry times when lakes disappeared. Besides this evidence of mud, Curiosity has found evidence of ancient lakes in older layers and also in younger mudstone. Nathan Stein, a graduate student at the California Institute of Technology led the investigation.>>[/quote]

What a wonderfully framed picture.I like how the salt flats have a crystal pattern on the surface.

[float=left][img2]https://upload.wikimedia.org/wikipedia/commons/9/9b/Hexagons%2C_Salar_de_Uyuni%2C_Bolivia_%282086104060%29.jpg[/img2][/float]What the ground looks like during the day.

Breathtaking and timeless image!

Beyond words to describe.

Thank you!

[url=https://apod.nasa.gov/apod/ap170415.html][img]https://apod.nasa.gov/apod/calendar/S_170415.jpg[/img] [size=150]Luminous Salar de Uyuni[/size][/url]

[b] Explanation: [/b] A scene in high contrast this thoughtful night skyscape is a modern composition inspired by M. C. Escher's lithograph [url=https://theartstack.com/artist/m-c-escher/phosphorescent-sea-july]Phosphorescent Sea[/url]. In it, bright familiar stars of Orion the Hunter and Aldebaran, eye of Taurus the Bull, hang in clear dark skies above a distant horizon. Below, faintly luminous edges trace an [url=https://www.nasa.gov/mission_pages/cassini/multimedia/pia17470.html]otherworldly[/url] constellation of patterns in mineral-crusted mud along the Uyuni Salt Flat of southwest Bolivia. The remains of an ancient lake, the Uyuni Salt Flat, [url=https://earthobservatory.nasa.gov/IOTD/view.php?id=84853]Salar de Uyuni[/url], is planet Earth's largest salt flat, located on the Bolivian Altiplano at an altitude of about 3,600 meters. Escher's 1933 lithograph also featured familiar stars in planet Earth's night, [url=https://apod.nasa.gov/apod/ap170407.html]framing The Plough[/url] or Big Dipper above waves breaking on a more [url=https://apod.nasa.gov/apod/ap140920.html]northern shore[/url].

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