A joint Australian-German research team led by Curtin University’s Dr Christian Hirt has created the highest-resolution maps of Earth’s gravity field to date — showing gravitational variations up to 40 per cent larger than previously assumed.
Using detailed topographic information obtained from the US Space Shuttle, a specialist team including Associate Professor Michael Kuhn, Dr Sten Claessens and Moritz Rexer from Curtin’s Western Australian Centre for Geodesy and Professor Roland Pail and Thomas Fecher from Technical University Munich improved the resolution of previous global gravity field maps by a factor of 40.
“This is a world-first effort to portray the gravity field for all countries of our planet with unseen detail,” Dr Hirt said. “Our research team calculated free-fall gravity at three billion points — that’s one every 200 metres — to create these highest-resolution gravity maps. They show the subtle changes in gravity over most land areas of Earth.”
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.
“Only a few years ago, this research would not have been possible,” Dr Hirt said. Via Gravity variations over Earth much bigger than previously thought.