On September 21, NASA released the first images captured by the James Webb Space Telescope of Neptune, the giant ice planet in our Solar System.
Neptune and its rings in images taken by the James Webb Telescope. (Image: NASA/ESA/CSA/STScI)
The new images provide astronomers with the clearest view of Neptune’s icy rings in 32 years, since the Voyager 2 spacecraft flew by the planet on its way out of the Solar System.
“It has been three decades since we last saw those faint dusty rings, and this is the first time we have observed them in near-infrared light,” said Heidi Hammel, a planetary scientist at the Association of Universities for Research in Astronomy (AURA).
In addition to the known narrow and bright rings, the new images from James Webb also reveal some fainter dusty rings around Neptune. Scientists had never seen these, even when Voyager 2 approached the planet in 1989.
The James Webb Telescope captures an image of Neptune and its 7 moons, with the most prominent being Triton above. (Image: NASA/ESA/CSA/STScI).
In images from the Hubble Space Telescope, Neptune often appears in its characteristic blue color. This blue is caused by methane in the atmosphere and does not appear in the new images because James Webb observes Neptune in near-infrared light. Since methane in Neptune’s icy clouds absorbs strong light at these wavelengths, areas without bright clouds and at high altitudes appear quite dark.
Another highlight is the series of bright patches in Neptune’s southern hemisphere. These are high-altitude ice clouds reflecting sunlight before being absorbed by methane in the clouds.
The images from James Webb show a band of high-altitude clouds surrounding a cyclone at Neptune’s south pole. Additionally, scientists discovered a thin, faint bright streak around the equator, which may be atmospheric circulation. The northern pole of Neptune also exhibited interesting light patterns.
James Webb provides scientists with images of 7 of Neptune’s moons. The bright spot above Neptune is its moon Triton. This moon is covered by a layer of condensed frozen nitrogen and appears brighter than Neptune itself, reflecting about 70% of sunlight.
