The quartet, who rocketed from NASA's Kennedy Space Center on Monday night, returned off the Southern California coast. It was the first human spaceflight to circle the globe above the poles
The recent intensification and more poleward location of the southern hemisphere belt of westerly winds have been linked to continental droughts and wildfires, including those in Australia
Sensors on the drone would assess sunlight reflected from the ice
The magnetic north pole is wandering about 34 miles (55 kilometers) a year