The animation above shows a rather surprising fact. Gravity on earth is not uniform everywhere. In some places it’s actually stronger than others.
“This visualization of a gravity model was created with data from NASA’s Gravity Recovery and Climate Experiment (GRACE) and shows variations in Earth’s gravity field.
Gravity is determined by mass. Earth’s mass is not distributed equally, and it also changes over time.
The colors in this image represent the gravity anomalies measured by GRACE. One can define standard gravity as the value of gravity for a perfectly smooth ‘idealized’ Earth, and the gravity ‘anomaly’ is a measure of how actual gravity deviates from this standard.
Red shows the areas where gravity is stronger than the smooth, standard value, and blue reveals areas where gravity is weaker.
Red represents an acceleration of 5·10⁻⁴ m/s², blue represents -5·10⁻⁴ m/s², for a legend of the colors see below.
GRACE is a collaborative endeavor involving the Center for Space Research at the University of Texas, Austin; NASA’s Jet Propulsion Laboratory, Pasadena, Calif.; the German Space Agency and the German Research Center for Geosciences, Potsdam.
You can see the scale below:
Gravity on earth varies from 976 to 983 Gal which is due both to altitude (there is an approximately 2 Gal difference from the top of Mount Everest to sea level) and latitude (gravity is stronger at the equator vs the poles due to centrifugal force and bulge.
Put another way, gravity on the Earth’s surface varies by around 0.7%, from 9.7639 m/s2 on the Nevado Huascarán mountain in Peru to 9.8337 m/s2 at the surface of the Arctic Ocean. In large cities, it ranges from 9.7760 in Kuala Lumpur, Mexico City, and Singapore to 9.8250 in Oslo and Helsinki.
Find this interesting? The Please share with a friend: