Deployed into low-Earth orbit from the International Space Station in July, the RainCube (Radar in a CubeSat), which is "no bigger than a shoebox," is a technology-demonstration mission to enable Ka-band precipitation radar technologies on a low-cost, quick-turnaround platform. In an initial demonstration, the satellite sent back images of a storm over Mexico in August, and in a second wave of images in September it caught the first rainfall of Hurricane Florence.
The RainCube is a prototype for a possible fleet of such devices, say researchers, that could one day help monitor severe storms, lead to improving the accuracy of weather forecasts, and track climate change over time.
"We don't have any way of measuring how water and air move in thunderstorms globally," says Graeme Stephens, director of the Center of Climate Sciences at NASA's Jet Propulsion Laboratory in Pasadena, California. "We just don't have any information about that at all, yet it's so essential for predicting severe weather and even how rains will change in a future climate."
The researchers are experimenting to see if shrinking a weather radar into a low-cost, miniature satellite can still provide a real-time look inside storms. RainCube'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.
"The radar signal penetrates the storm, and then the radar receives back an echo," says principal Investigator Eva Peral. "As the radar signal goes deeper into the layers of the storm and measures the rain at those layers, we get a snapshot of the activity inside the storm."
RainCube is seen as a first demonstration that a mini-rain radar can work, but, say the researchers, it is not meant to fulfill a mission of tracking storms all by itself. Being miniaturized, it is less expensive to launch, and as a result, many more of such satellites could be