Explanation: The weathered and layered face of Mount Mercou looms in the foreground of this mosaic from the Curiosity Mars rover's Mast Camera. Made up of 21 individual images the scene was recorded just after sunset on March 19, the 3,063rd martian day of Curiosity's on going exploration of the Red Planet. In the martian twilight high altitude clouds still shine above, reflecting the light from the Sun below the local horizon like the noctilucent clouds of planet Earth. Though water ice clouds drift through the thin martian atmosphere, these wispy clouds are also at extreme altitudes and could be composed of frozen carbon dioxide, crystals of dry ice. Curiosity's Mast Cam has also imaged iridescent or mother of pearl clouds adding subtle colors to the martian sky.
<<At the start of March, NASA’s Curiosity Mars rover began approaching an impressive rock formation that scientists dubbed “Mont Mercou,” a nickname taken from a mountain in France. Standing about 6 meters tall, the outcrop is captured in all its majesty in a new selfie, as well as in a pair of panoramas that offer a 3D view. The selfie shows Curiosity in front of Mont Mercou with a new drill hole nearby at a rock sample nicknamed “Nontron” – the mission’s 30th sample to date.
Curiosity’s drill powderized the sample before trickling it into instruments inside the rover so the science team could get a better understanding of the rock’s composition and what clues it might offer about Mars’ past. This area is at the transition between the “clay-bearing unit” Curiosity is departing and the “sulfate-bearing unit” that’s ahead on Mount Sharp, the 5-kilometer-tall mountain that the rover has been rolling up since 2014. Scientists have long thought this transition might reveal what happened to Mars as it became the desert planet we see today.
France’s Mont Mercou is located near the village of Nontron in the southeast of the country. The team chose Nontron-related nicknames for this part of the Red Planet because Mars orbiters detected nontronite, a type of clay mineral found close to Nontron, in the region. Surface missions assign nicknames to landmarks to provide the mission’s team members a common way to refer to rocks, soils, and other geologic features of interest.>>
Re: APOD: The Shining Clouds of Mars (2021 Jun 05)
Posted: Sat Jun 05, 2021 4:29 pm
by XgeoX
ToucanSam wrote: ↑Sat Jun 05, 2021 1:09 pm
At first glance it's difficult to tell whether you're on Earth or Mars. It look as if you're in the Gobi Desert, the American southwest, or something.
Yes I wholeheartedly agree! This, to me, is the most earth looking photo i’ve seen of Mars. Part of it not the clouds but the dark gray sky after sunset which looks like overcast. Hard to believe that if you stepped out there you would be unconscious in seconds and dead in a few minutes.Looks can be deadly deceiving!
Eric
Re: APOD: The Shining Clouds of Mars (2021 Jun 05)
Posted: Sat Jun 05, 2021 4:51 pm
by orin stepanek
Now I'm hungry for an almond Joy!
Wow; reminds me of a cloudy day in the Rockies!
Re: APOD: The Shining Clouds of Mars (2021 Jun 05)
Posted: Sun Jun 06, 2021 12:59 pm
by DGH
This looks like sedimentary rock.
Re: APOD: The Shining Clouds of Mars (2021 Jun 05)
Posted: Sun Jun 06, 2021 2:09 pm
by neufer
DGH wrote: ↑Sun Jun 06, 2021 12:59 pm
This looks like sedimentary rock.
https://en.wikipedia.org/wiki/Mount_Sharp wrote:
<<Mount Sharp, officially Aeolis Mons, appears to be an enormous mound of eroded sedimentary layers sitting on the central peak of Gale. It rises 5.5 km above the northern crater floor and 4.5 km above the southern crater floor, higher than the southern crater rim. The sediments may have been laid down over an interval of 2 billion years, and may have once completely filled the crater. Some of the lower sediment layers may have originally been deposited on a lake bed, while observations of possibly cross-bedded strata in the upper mound suggest aeolian processes. However, this issue is debated, and the origin of the lower layers remains unclear. If katabatic wind deposition played the predominant role in the emplacement of the sediments, as suggested by reported 3 degree radial slopes of the mound's layers, erosion would have come into play largely to place an upper limit on the mound's growth.
On October 8, 2015, NASA confirmed that lakes and streams existed in Gale crater 3.3 - 3.8 billion years ago delivering sediments to build up the lower layers of Mount Sharp. On February 1, 2019, NASA scientists reported that Curiosity had determined, for the first time, the density of Mount Sharp in Gale crater, thereby establishing a clearer understanding of how the mountain was formed.>>