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I am trying to determine which on Earth's surface has the lowest gravity. Googling is not finding anything concrete. My natural inclination would be to think of Mount Chimborazo in Ecuador, being on the equator (centripetal force) and also being the furthest point from the Earth's center. However, the GRACE gravity map has the area listed in red for high gravity, presumably due to local mineral anomalies or mantle structure.

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  • $\begingroup$ What is wrong with the color coding of Grace? en.wikipedia.org/wiki/File:Geoids_sm.jpg . Lowest gravity is over oceans, and that is reasonable since the gravitational field depends on the mass below, and the smaller the radius the less mass there, not more as you seem to assume. $\endgroup$ – anna v Mar 20 '12 at 11:36
  • $\begingroup$ The colour coding of GRACE is fine. The lack of an X to mark the lowest point is my question. $\endgroup$ – dotancohen Mar 20 '12 at 11:44
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    $\begingroup$ Programmers solution: fetch GRACE data by running scripts on an interactive map. Find lowest point. I'll try this later :) $\endgroup$ – Manishearth Mar 20 '12 at 12:01
  • $\begingroup$ It is the darkest blue, and it is not one point but several, all under water: csr.utexas.edu/grace/gravity $\endgroup$ – anna v Mar 20 '12 at 12:05
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    $\begingroup$ Relevant article $\endgroup$ – dotancohen Sep 16 '13 at 14:55
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Lowest gravity on earth surface is near Sri Lanka based on the articles below.

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  • $\begingroup$ The links you provide seem to only give poor interpretations of the gravitational data from GRACE. When you account for newer GRACE data, additional sources, and factor the topology of Earth's surface into the linked data, you find that Sri Lanka is not near the place of lowest gravity. $\endgroup$ – Jim Mar 1 '17 at 13:42
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A late 2013 research paper publish on Science Daily by Curtin University mentions that the point on the Earth's surface with the lowest gravity is Mount HuascarĂ¡n in Peru.

The new gravity maps revealed the variations of free-fall gravity over Earth were much bigger than previously thought.

Earth's gravitational pull is smallest on the top of the Huascaran mountain in the South American Andes, and largest near the North Pole.

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  • $\begingroup$ @Jim: I was a bit wary of changing the accepted answer to my own answer seeing as I'm the OP, but I think that you are right. The data in the research paper was not available at the time this question was originally asked. $\endgroup$ – dotancohen Mar 1 '17 at 14:09
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According to http://en.wikipedia.org/wiki/Gravity_of_Earth#Comparative_gravities_in_various_cities_around_the_world Mexico City has the lowest gravity of any city. However the article doesn't mention mountain tops.

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  • $\begingroup$ Thank you. I did see that, but as you mention it does not pertain to the entire Earth's surface but rather only to the relatively small portions of the Earth's surface which constitute large human population centers. $\endgroup$ – dotancohen Mar 20 '12 at 11:30
  • $\begingroup$ Given the analysis you linked to it's surprising that someone hasn't worked out the answer to your question, but Googling has failed to find it. If someone finds an authoritative answer I'd be very interested to hear it. $\endgroup$ – John Rennie Mar 20 '12 at 11:36
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One of the places with lower gravity is Hudson Bay, Canada, and this explains why and how that works:

http://science.howstuffworks.com/environmental/earth/geophysics/missing-gravity.htm

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  • $\begingroup$ Can you add the content from that link to your answer without making exact copies? Link answers are not accepted. $\endgroup$ – Yashas Mar 1 '17 at 7:37
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this is a gravity map published by NASA

Sri Lanka and south India has least gravity level on the earth. As you say this is almost the equatorial region and this area has minimal gravity as measured by the SriLankan government. the point on the Earth's surface with the lowest gravity is hiriwadunna in Sri Lanka www.map.google.com

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  • $\begingroup$ Thank you. Other answers mention that GRACE map, but yours is the first to include it for easy reference. $\endgroup$ – dotancohen Apr 12 '20 at 14:57
  • $\begingroup$ goo.gl/maps/vBmyPd1kYhNb5ndE8 this is the google map link for it. visit and feel the gravity $\endgroup$ – Nilupul Heshan Apr 17 '20 at 13:15
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Probably Mt. Chimborazo has the MOST gravity, as being in the "fattest" part of the planet and as one of the highest mountains you will have LOTS of mass generating more gravity (remember the more mass, the more gravity).

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    $\begingroup$ But the higher you go up a mountain the farther you are from the rest of the Earth and $1/r^2$ is pretty significant dropoff. Which one wins? More mountain mass or being closer to the surface of the Earth? $\endgroup$ – Brandon Enright Nov 26 '13 at 22:22
  • $\begingroup$ Gravitational acceleration at the equator is 9.8144 m/s^2, vs 9.8322 m/s^2 at the poles; the International Gravity Formula can help, giving 9.761 m/s^2 atop Chimborazo. $\endgroup$ – Dave Jarvis Dec 30 '15 at 3:03
  • $\begingroup$ @BrandonEnright Going high up would work if you went in a balloon; because you're getting away from the CoM without adding any mass below your feet. But if you climb a mountain, you've now got a lot of additional mass to attract you. It's a bit like if you moved to a larger planet whose mean surface was at the top of the mountain. $\endgroup$ – Oscar Bravo Mar 1 '17 at 7:55
  • $\begingroup$ @OscarBravo "A lot" is pretty subjective. Gravity has a linear dependence on mass; while it has an inverse square dependence on distance. Compared to the entire mass of the planet, the additional mass of the mountain is probably insignificant. $\endgroup$ – JMac Oct 6 '17 at 12:23

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