The National Geodetic Survey (NGS) has published a technical report that describes options for how NGS can implement a time-dependent geopotential datum and thus a time-dependent geoid model. My last ...

My last column highlighted some of the feedback provided by guest presenters at the NGS’ 2017 Geospatial Summit held on April 24-25 in Silver Spring, Maryland. That column also provided a discussion ...

Earth, in most renderings, is a smooth sphere with a glossy complexion—a blue marble, as pictures snapped from space have shown us. Earth scientists know that’s not exactly true. Earth, in fact, is an ...

Take a clay model of Earth and squish it with your fingers, and the result may look similar to the geoid — the latest and best-ever map of our planet's gravitational field. The latest Earth gravity ...

For years, researchers have tried to pinpoint how an area deep in the Indian Ocean with lower gravitational pull came to be. A team in India may have figured it out. The area in question is called the ...