Turtles may migrate using Earth's magnetic field

New research indicates that sea turtles seem to navigate across hundreds of miles of open ocean using Earth's magnetic field. Previous experimental studies suggested that sea turtles use geomagnetism to navigate, but this study, published in Science Advances, was purely observational: Researchers attached devices measuring location and compass direction (the way a turtle was facing at a given moment) to six female green sea turtles that took about a month to navigate more than 1,000 miles (1,600 kilometers) westward across the Indian Ocean. The satellite tags, developed over the course of five years specifically for this purpose, measure compass headings to within 10° and location to within 100 meters.