is the waistline of the earth expanding?

[Swoop1]

I juts read a news article about the discovery of a roman road under a garden near Stirling- the road surface was beneath about a meter of earth.

This got me to thinking- dangerous, I know, as most archeological sites, which often expose ancient surface features, involve digging down some distance.

Does this mean that over time, the earth is expanding in circumference?

[Ags]

No, it only means that if an archaeological site is not buried by later deposits, and instead stays on the surface and is exposed to the elements, most likely it gets completely eroded away and disappears.

[Space Hopper]

Not sure about all that, but i do know my trousers have been expanding in circumference for more years than i care to remember.....😀😯😫

[Mr H in Yorkshire]

1 hour ago, Space Hopper said:

i do know my trousers have been expanding in circumference for more years than i care to remember

Ah yes that body type gets more common as one gets older. Ectomorph, Mesomorph, Endomorph, Space Hopper. 🙂

[Swoop1]

2 hours ago, Ags said:

No, it only means that if an archaeological site is not buried by later deposits, and instead stays on the surface and is exposed to the elements, most likely it gets completely eroded away and disappears.

But the later deposits- where do they come from?

I expect some is from redistrbution of material by the elem,ents but, more material arrives on earth from space every day surely?

[inedible_hulk]

There’s a whole branch of archaeology interested in site formation processes, but for a simple answer see: https://www.yac-uk.org/news/ask-the-archaeologist-why-are-the-things-from-the-olden-days-under-the-ground

[saac]

I do believe a known amount of cosmic dust falls onto the earth each year so in theory I guess the radius of the Earth could increase (very very slightly).  I suspect in practice most of what is gained is redistributed by our ever increasing dynamic weather system.

Jim  

[globular]

34 minutes ago, saac said:

I do believe a known amount of cosmic dust falls onto the earth each year so in theory I guess the radius of the Earth could increase (very very slightly).  I suspect in practice most of what is gained is redistributed by our ever increasing dynamic weather system.

Jim  

Gravity does a good job of keeping stuff on Earth, but a faint stream of lightweight gasses, mostly hydrogen, helium and oxygen, is continually escaping from the fringes of our atmosphere. (Particularly dense near the poles, where gas ionized by the sun flows out along the magnetic field lines.)  Several hundred tons of mass escape to space every day, significantly more than what we’re gaining from dust (which is about 40 tons per day).

Edited November 3, 2023 by globular

[saac]

37 minutes ago, globular said:

Gravity does a good job of keeping stuff on Earth, but a faint stream of lightweight gasses, mostly hydrogen, helium and oxygen, is continually escaping from the fringes of our atmosphere. (Particularly dense near the poles, where gas ionized by the sun flows out along the magnetic field lines.)  Several hundred tons of mass escape to space every day, significantly more than what we’re gaining from dust (which is about 40 tons per day).

Yes but gas infall or outfall I would think is not really the cause of accretion of material on the surface and hence does not contribute to any change in radius. It contributes to change in mass for sure but not dimension.  Again any increase will be of insignificant orders of magnitude against the radius of the Earth but it is an interesting academic question. 

Jim  

Edited November 3, 2023 by saac

[Zermelo]

For seriously expanding waistlines, you need to look to Saturn ...

Iapetus:

 

Pan:

Atlas:

[saac]

These researchers put the amount of cosmic dust (micrometeorites) gained each year at around 5000 metric tonnes.  No doubt that will come with a fair margin of error. If that were distributed evenly across the surface of the planet what thickness (increase in waistline) would it represent?  This reminds me of the number of angels dancing on a pin head puzzle or maybe even a Fermi question; best contemplated with a few whiskies  

Jim 

https://www.scientificamerican.com/article/antarctic-study-shows-how-much-space-dust-hits-earth-every-year/

[Gfamily]

13 hours ago, saac said:

These researchers put the amount of cosmic dust (micrometeorites) gained each year at around 5000 metric tonnes.  No doubt that will come with a fair margin of error. If that were distributed evenly across the surface of the planet what thickness (increase in waistline) would it represent?  This reminds me of the number of angels dancing on a pin head puzzle or maybe even a Fermi question; best contemplated with a few whiskies  

Jim

Given that Google suggests the area of the earth is about 510 million km^2, it's about 10g per km^2 per year.  

Less than a tablespoon of space dust over the area of an OS grid square. It would take a million years for this to equate to a tablespoon per square metre, and if you consider how thinly a tablespoon of sand would spread ...

Save the few whiskies for a different question. 

 

 

[robin_astro]

I guess plants turning our once CO2 rich atmosphere into solid material presumably added a bit in coal seams, though by reversing the process we must be currently causing some net shrinkage. The process is perhaps detectable locally around my observatory where after a decade or so there is no longer a  gap between the bottom of the doors and  the lawn. Long term everything once on the surface ends up underground due to plate tectonics.

Robin

[ONIKKINEN]

Check this out:

 

If you're into ancient Roman history, this YouTube channel will definitely interest you outside of this one specific question. Goldmine of information really.

[maw lod qan]

I've wondered about this myself.

Over the years I worked on tomato farms I have found many arrow heads and other points. 

Many date several thousand years old.

I've always questioned how you found some 4 to 5 feet in undisturbed soil?

The only thing I do know for certain is my waist line is continously expanding!

[saac]

17 minutes ago, maw lod qan said:

The only thing I do know for certain is my waist line is continously expanding!

Something I sadly have in common and it aint due to cosmic dust  

Jim 

[Gfamily]

40 minutes ago, maw lod qan said:

I've always questioned how you found some 4 to 5 feet in undisturbed soil?

Worms, moles and other burrowing animals mean that soil is constantly being turned over, and plant debris tends to stay on or near the surface. Meaning that non organic material tends to migrate to lower levels.