Comments on: The Earth’s Gravitational Field Is Lumpy

By: Techgeek

Techgeek — Sun, 07 Nov 2010 11:23:12 +0000

Does this mean rockets launched from India would be easier to enter the orbit?? Shutdown Florida station then!!!!

By: Lily

Lily — Wed, 24 Mar 2010 18:38:18 +0000

Rght over Japan… tsunami and earthquake problem?

By: Matt

Matt — Mon, 15 Jun 2009 16:57:32 +0000

So red means evil, right?

By: Jef

Jef — Mon, 08 Jun 2009 19:34:24 +0000

Oh, I nearly forgot. To those wondering why those two areas are so different, here’s the theory scientists have. The big Sumatran earthquake in Dec 2004 in the Indian Ocean has left a “scar” in the gravity field. I observe that the “ring” along Indonesia corresponds with the famous “ring of fire” we all learned about in Grade 3/4, and presume this would have something to do with molten rock constantly being deposited and packed down in the same place over and over again (creating a mascon and therefore a gravity field anomoly).

By: Jef

Jef — Mon, 08 Jun 2009 19:22:59 +0000

-sigh- Reading these comments has been frustrating. A moment’s observation of the models shows a clear correlation between the color (ranging from blue to hot-pink) and diameter of the sphere. Blue-colored areas don’t “stick out” as much as the hot-pink areas. So that answers THAT question. To the poster who claimed that this has ANYTHING to do with “lumpiness”, actual topography, or the fact that the models are “exaggerated” is just plain wrong. This is NOT a depiction of physical shape, it is a map of where gravity is the strongest (Indonesia) versus the weakest (India). This occurs because of high concentrations of mass (‘mascons”) which do not necessarily “stick out” as mountains. Put another way, the earth isn’t made up of uniformly dense material. Some of it is fluffy, some of it is packed hard. The hard-packed stuff has a higher gravity field than the fluffier stuff. The model, then, is how the earth would have to be shaped IF a) you wanted the gravitational field to stay the same as it is now and b) the earth was made up of the same uniform material throughout. Does that clear it up?

By: sailingsoul

sailingsoul — Tue, 19 May 2009 23:07:41 +0000

The best way to deliver this type of data might be with a rotating ball effect. SS

By: Andrew

Andrew — Mon, 04 May 2009 03:53:17 +0000

What’s amazing is we don’t even understand gravity. or light.

By: adam

adam — Mon, 04 May 2009 00:27:24 +0000

What is going on in Indonesia? Any why is India wicked light? (I might have them backward, I dont know if the red is heavy, just assuming)

By: matt

matt — Wed, 29 Apr 2009 03:02:11 +0000

gravity can also be measured by a ground-based machine. they showed it on mythbusters one time, and if i can remember correctly, they fired a laser into a vacuum chamber, and measured how long it took (since if there was more gravity, it would fall faster due to relativity) to get to the other side. it was extremely accurate, and the myth was busted.

By: anon

anon — Wed, 29 Apr 2009 00:11:30 +0000

Satellites don’t stay in a perfect orbit, because the earth is not a uniform sphere. They can however find their position in relation to fixed points on the earth. By measuring the satellites’ slight tendency to veer towards or away from predicted orbit (as if earth was a perfect sphere) this “lumpiness” can be mapped. Do note that the 3D models are very exaggerated.