Ruf’s constellation of microsatellites, named CYGNSS, gets around that problem in a smart way. It takes advantage of the GPS signals that satellites are constantly beaming down to Earth. Those signals use a longer wavelength than typical weather satellites, which means they can penetrate through rain without suffering too much damage. CYGNSS’s GPS receivers (like the one in your phone) listen in on those signals, and when they bounce back from Earth, the satellites measure how distorted the signal became on the surface. More distortion means a rougher ocean, which means a tougher storm.