Two identical satellites fly 220 kilometers apart above the Earth, firing a laser between them precisely enough to notice a change in distance smaller than the width of a red blood cell, and that flicker is how scientists now weigh the water moving beneath entire continents

Invisible water moving through continents now leaves a gravitational fingerprint that satellites can read. The post Two identical satellites fly 220 kilometers apart above the Earth, firing a laser between them precisely enough to notice a change in distance smaller than the width of a red blood cell, and that flicker is how scientists now weigh the water moving beneath entire continents appeared first on Space Daily .