[UPDATE (April 5, 2011): It turns out some of the descriptions I used below to describe a geoid were not accurate. I refer you to this page at the University of Oklahoma for a good description. I’ve ...

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 ...

The Earth’s geoid is the shape the planet would assume if its surface were made of water. Naturally, there’s little dispute over the shape of the geoid over the oceans, where it varies by only 100 ...

Credit: International Centre for Global Earth Models (ICGEM) / E. S., Barthelmes, F., Reißland, S., Elger, Like all scientific mysteries, the Indian Ocean geoid low (IOGL) — also known as the Indian ...

Editor’s Note: Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. There is a “gravity hole” in the Indian ...

The Indian Ocean Geoid Low (IOGL), a significant gravitational anomaly, has puzzled scientists for decades. Research suggests it formed due to interactions between tectonic plates and mantle plumes ...

The Indian Ocean geoid low is one of the most profound gravitational anomalies on Earth. Earth is often depicted as a perfect sphere. But in reality, the planet's shape is irregular, much like a ...

As high-precision GNSS horizontal and vertical data becomes less expensive to collect, greater attention must be paid when reconciling vertical datasets. In 2013, I wrote two articles entitled ...

Deep within the Indian Ocean lies an extraordinary feature that has puzzled scientists for over seven decades—the Indian Ocean Geoid Low (IOGL). This vast “gravity hole,” the largest of its kind on ...

Part 1 of this column appeared in the June Survey Scene newsletter, Part 2 appeared in the August newsletter. Upcoming Survey Scene newsletters will carry additional columns in this series. In my ...