Science stories of the week

EDIT: Deleted (as best can be). Negligently clicked the wrong thread for depositing this item.
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From the article

"An asteroid struck Mars 11 million years ago and sent pieces of the red planet hurtling through space. One of these chunks of Mars eventually crashed into the Earth somewhere near Purdue University and is one of the few meteorites that can be traced directly to Mars.

But once Lafayette hit Earth, the story gets a little muddy. It is known for certain that the meteorite was found in a drawer at Purdue University in 1931. But how it got there is still a mystery."

Paper


Article

https://phys.org/news/2024-11-meteorite-evidence-liquid-mars-million.html

Gawdzilla Sama
 
Here is the real paper, for those like me that always suspect pop-sci journos tend to screw up the explanation: https://www.nature.com/articles/s41467-024-52126-7

Though in this case they seem to have got it right.

This reminds of a similar recent geophysics article, also to do with erosion of the lithosphere beneath continental blocks. I’m trying to remember what forum, and where and when, I posted something about it…..
 
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Found it: https://www.scienceforums.net/topic/134465-explanation-of-raised-plateaux-inland-from-ocean-margins/

Hope it’s not bad form to link to a thread on a rival forum, but the discussion was quite interesting and too long to repeat here. The key point is to understand that the rigid upper part of the mantle that forms the base of the lithosphere is denser than the viscous asthenosphere it sits above. So it is potentially unstable and can “delaminate”, becoming detached from the crust above and will then sink down into the asthenosphere.

I took a while to grasp this because when I learnt my geophysics as a teenager in the 1970s, people spoke of the crust and lithosphere as being the same thing, whereas now we view the lithosphere as the crust PLUS a cooled and solidified upper layer of mantle material, effectively welded onto the bottom of the crust.
 
Why is what I posted, funny?
I think it's the title, "Dripping," pop sci tends to dramatise descriptions for headlines for hits and sales.

The Media is guilty as are some popular science magazines, "New scientist" does this a lot.
Physics.org is quite level headed but I have got into deep water with articles there too, posting on a "hard" science site.

16 months on this site however I have changed my view of SF, some posters on here are no slouches when it comes to certain subjects.
Some "hard" areas popping up here where I have been diving into my text books! And still none the wiser!
All good stuff.
 
I think it's the title, "Dripping," pop sci tends to dramatise descriptions for headlines for hits and sales.

The Media is guilty as are some popular science magazines, "New scientist" does this a lot.
Physics.org is quite level headed but I have got into deep water with articles there too, posting on a "hard" science site.

16 months on this site however I have changed my view of SF, some posters on here are no slouches when it comes to certain subjects.
Some "hard" areas popping up here where I have been diving into my text books! And still none the wiser!
All good stuff.
SF’s content ebbs and flows, but maybe that’s why James R painstakingly moderates as he does, to keep the hard science sections void of nonsense. I didn’t think this article was nonsense though, but the idea of the Earth’s crust “dripping” did catch my eye. ;)
 
I too assumed there was a pun there. Just as trickle-down economics led to a depression, so too can trickle-down tectonics. I remember seeing someone do this with bitumen when I was in college - it took several years for the drip to complete. Bitumen, though it can appear as somewhat solid is technically a highly viscous liquid. One can do the same thing with glass, though the drip will likely take many centuries.
 
I felt genuinely “depressed” about it. lol
Eh? Why did it take you that way? These are geological processes that take place over millions of years and have always done. There’s nothing bad about them, so far as I can see.
 
Eh? Why did it take you that way? These are geological processes that take place over millions of years and have always done. There’s nothing bad about them, so far as I can see.
Maybe I’m focusing on the “loss” or seeing this as mainly loss, and not simply geological changes that the Earth goes through. Wouldn’t our planet become increasingly vulnerable over time? Granted, a long period of time, but I guess the idea of that makes me feel a little melancholic.
 
Maybe I’m focusing on the “loss” or seeing this as mainly loss, and not simply geological changes that the Earth goes through. Wouldn’t our planet become increasingly vulnerable over time? Granted, a long period of time, but I guess the idea of that makes me feel a little melancholic.
Not at all. This is just one of many geophysical tectonic processes going on all the time in an endless cycle. Don't worry about the crust being "lost". As a matter of fact, over geological time the amount of continental crust on the Earth's surface seems to have increased, due to the fractionation process that occurs when lower melting point, less dense mineral fractions are ejected onto the surface by volcanism.

In fact, now you make me read this again more closely, the journos have indeed got it wrong. They speak of the "crust" dripping into the mantle but that is not what is happening. As my earlier post pointed out, the lithosphere consists of crust on top and also a layer of cooled, rigid mantle material beneath. It is that mantle layer which is denser than the underlying, plastic asthenosphere and it is just that layer that "drips" down into it. In doing so it tends to pull on the crust supporting it, causing a depression.

The journos have made the same error I did before, with that other article I posted, of equating lithosphere with crust, when lithosphere has 2 components: crust and a denser rigid mantle layer.

Relax, wegs, it's all fine. :cool:
 
I too assumed there was a pun there. Just as trickle-down economics led to a depression, so too can trickle-down tectonics. I remember seeing someone do this with bitumen when I was in college - it took several years for the drip to complete. Bitumen, though it can appear as somewhat solid is technically a highly viscous liquid. One can do the same thing with glass, though the drip will likely take many centuries.
A treacle down effect?


No connection to Br'er Rabbit,I suppose ?
 
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