Specifically, the ice giants have a relative surplus of gaseous methane, which gives them their characteristic blue hue in visual images like those captured by the Hubble Space Telescope. The solar system’s ice giants - Neptune and Uranus - are richer in heavy molecules than the gas giants Jupiter and Saturn, which are almost entirely composed of hydrogen and helium. “It has been three decades since we last saw those faint, dusty bands, and this is the first time we’ve seen them in the infrared,” said Heidi Hammel, a Neptune expert and JWST scientist, in a press release. Some of these rings are so faint that they haven’t been detected since NASA’s Voyager 2 probe became the first spacecraft to closely observe Neptune during its flyby in 1989. Perhaps the most striking aspect of the new image is Neptune’s ethereal ring system.
However, thanks to JWST’s space-based vantage point, impeccable stability, and impressively large (21-foot-diameter) primary mirror, the telescope was able to capture Neptune’s features with a clarity that hasn’t been achieved in more than 30 years. Located some 30 times farther from the Sun than Earth, Neptune, the solar system’s most distant planet, isn’t an easy world to photograph. Neptune’s delicate rings and even fainter dust bands come into clear focus in this recent image captured by NASA’s James Webb Space Telescope (JWST).