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Science

DavidDvorkin

(20,541 posts)

14. Gravity is not uniform because the Earth's mass is not uniformly distributed

Reply to truedelphi (Original post)

Fri Dec 14, 2012, 10:06 PM

Dec 2012

It varies greatly in density from one place to another. The Earth doesn't consist of just one sort of stuff, which is the same everywhere.

The difference isn't noticeable to human senses, but instruments can detect it.

The same is true of other bodies, of course. Google "lunar mascons" for an interesting story from the days of the Apollo project. Or you could Google "perilune wiggle", which should get you a lot of the same URLs, but which is a niftier phrase.

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Can somebody explain a few thngs about gravity - [View all] truedelphi Dec 2012 OP

Until a day or two ago, I thought gravity was consistent, too. lob1 Dec 2012 #1

Density differences lead to very tiny gravity "anomalies" Odin2005 Dec 2012 #6

This is very serious. jtuck004 Dec 2012 #2

You might enjoy this anecdote - truedelphi Dec 2012 #8

LOL. jtuck004 Dec 2012 #11

Gravity is between two masses. Weight is the amount of attraction. Festivito Dec 2012 #3

Pretty good explanation - I can follow what you are saying truedelphi Dec 2012 #9

Like why does the earth have more pull than the mostly empty space around it? DCKit Dec 2012 #4

Wouldn't the height above sea level affect gravity, oldbanjo Dec 2012 #5

Gravity isn't based on sea level jeff47 Dec 2012 #7

I think there were indications in the article that that is so truedelphi Dec 2012 #10

Gravity depends on the distribution of the matter "creating" it caraher Dec 2012 #12

OK, so here: Like, ya wakes up in the morning, and ya decides to go to the diner for some chow, struggle4progress Dec 2012 #13

Here's something I found on the FB site truedelphi Dec 2012 #17

Gravity is not uniform because the Earth's mass is not uniformly distributed DavidDvorkin Dec 2012 #14

Somehow none of the science teachers I had ever mentioned any of this - truedelphi Dec 2012 #15

It's still common to teach gravity as though all bodies were point sources DavidDvorkin Dec 2012 #16