The RainCube flight system in integration and test, with the solar panels and radar antenna deployed.

NASA’s RainCube, a satellite small enough to fit in a backpack, shrinks weather radar into a low-cost, miniature satellite that can provide a real-time look inside storms. The satellite’s umbrella-like antenna sends out chirps, or specialized radar signals, that bounce off raindrops, bringing back a picture of what the inside of the storm looks like.

Because RainCube is miniaturized, making it less expensive to launch, many more of the satellites could be sent into orbit. Flying together like geese, they could track storms, relaying updated information on them every few minutes.