If you look at a map of Earth's gravity, you will see a huge blue spot south of India, indicating a region where gravity is weaker than average. This spot is called the Indian Ocean Geoid Low (IOGL), and it is the largest gravity anomaly on our planet.A gravity anomaly is a difference between the actual gravity measured at a location and the theoretical gravity expected for a perfectly smooth and spherical Earth. But Earth's gravity isn't perfectly uniform and variations in mass distribution beneath the surface cause fluctuations in gravitational pull.Gravity anomalies can be caused by variations in the...