This map represents data captured by the Microwave Radiometer (MWR) aboard NASA’s Juno spacecraft, indicating the heat rising just below the surface of Jupiter’s moon Io. While infrared instruments measure the temperature of the moon’s surface, the MWR’s lower frequency microwave channels (0.6 and 1.25 gigahertz) can penetrate 6 to 20 feet (2 to 6
This graphic illustrates the areas of Jupiter’s moon Io sampled by the Microwave Radiometer (MWR) instrument aboard NASA’s Juno spacecraft during two close flybys. The superimposed black lines show the instrument’s footprints during Perijove 57 on December 30, 2023, when the spacecraft primarily mapped the Northern Hemisphere. The blue lines represent Perijove 58 on February