I wonder if UCL could run the same analysis for the curious erosion around the Sphinx enclosure.
The mountains and ridges on Mars – which some believe are carved from melting ice – can also be formed by landslides, according to a paper published in Nature Communications on Thursday. Scientists, led by the eggheads at University College London in England, have effectively cast doubt over previous studies that support the …
That's centuries of passing camels stopping for a piss, everybody knows that.
More seriously, that's nothing more than ventifacts caused by the same aeolian processes that produced the yardang that makes up the body of the Great Sphinx. In English, wind driven sand opened up existing cracks in the limestone.
Have you Brits given the poor critter his beard back yet?
That is rather fast, when acceleration due to gravity is only 3.8m per s squared.
Quick back-of-fluoxetine-packet calculation suggests:
In free fall (discounting thin martian atmosphere and any stubborn mountain goats) you'd cover 1.3Km before reaching that speed. I know they've got some tall mountains on Mars, but .... wow
One has to remember that the atmosphere on Mars is very thin, and will cause much less drag on falling masses. However, I expect that the estimate of 360 kph down a slope is still just an outside guess, and may be a rare event. Best to go there and observe.
I just got around to reading the linked articles. I have no idea where UCL News got the 360km/hr number. The paper published in Nature says "We infer that the velocity of the martian landslide could range between 77 m/s and 345 m/s.". That's 277km/hr to 1242km/hr(‽‽‽) ... However, it goes on to say "the inferred velocity may be overestimated". Gee, you think?
Note also that TFA does NOT say there is no ice or water on Mars. What it says is that for some landslides, ice or water is not needed to create the formations observed.
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 For us unenlightened Yanks, that's around 170 to 770MPH, or 250 to 1130 feet/sec.
Dry lahars behave like water. This is the desire for water overriding science. I've been saying for ages that most of the water features on Mars could be created by sand and wind and gravity. I had the misfortune to have a science professor for a dad and he had dragged us across miles to see such things as laminated sand stones created by wind blown dunes in Scotland. At other times merely playing in sand reveals many of the water features found on Mars. The dry air there may even help to account for 'lake beds' where static causes dust to float resulting in the flat plains seen on Mars, and also at the bottom of craters on asteroids and the Moon. Its always worth remembering that the wear and tear on Egyptian monuments in 3000 years is quite severe in places. Mars has probably been bone dry for 3.5Billion!
This. When you let wishful thinking and culture set the *conclusion* to your experiments, you no longer have science.
No one denies the observations (and still is considered sane ;) ), but many many times I consider the conclusions must be taken with a massive grain of salt!
Did you see where I typed "suggested", "one method" and "could have"? There is a reason I used those words ...
On the other hand, how was the weather when you visited Mars to confirm you emphatic assertion that Mars "has been bone dry for 3.5Billion!"? Have you shared your first-hand data with other scientists, so we can stop the charade of mars robots?
While in this instance the cause might indeed be flowing sand and dust, there are plenty of other places on the surface of Mars where it is clear that liquid water (even if only temporary and periodically) has flowed across the landscape.
Can you tell us which ones these are? We assume things are created by water on Mars because similar things are created by (or with) water here. That does not mean the only mechanism to create them is water. Contrarily, the very dryness of Mars can allow dust and rocks to flow like water far more easily than it can here on earth. Without any water to prevent or dampen activity rocks and dust, once fluid, flow very freely - on a gentle slope they behave as a fluid, but with far more erosive power.
And wind can blow dust that, with overnight dews etc can form layers that are identical to deposits you'd expect from water.
Someone should get a dehydrated sandpit in a low atmospheric pressure chamber and have a play - there's a few PhDs in that.
I believe that signs of hydrated minerals have been found at several points. These only form in the (possibly temporary) presence of water.
This is the first legitimate-looking source I found for the above, there may be others:
“While we aren’t ruling out the presence of ice, we know is that ice wasn’t needed to form the long run-outs we analysed on Mars,” said Tom Mitchell, co-author of the paper and an associate professor of earthquake geology and rock physics at University College London.
I wonder if the reason they cannot find ice is that they are looking at the wrong time. Maybe in the storms or the extreme cold is when they need to be looking? With the temperature fluctuation they way it is, maybe it goes to a gas during the day and ice at night.
I would suggest the same reason why the FBI and CGHQ cannot find anything before it happens is they are looking at too much data, the wrong time, and in the wrong places.
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