New images from NASA’s James Webb Space Telescope, released Wednesday, show the clearest images of Neptune and its hard-to-see rings in decades.
According to Heidi Hammel, an interdisciplinary scientist working on the Webb telescope, it’s the best view of the planet’s dusty rings since the Voyager 2 spacecraft flew past Neptune in 1989 on its way out of the solar system.
“This is the first time we’ve seen them in the infrared,” Hammel said.
The new snapshots show faint dusty rings around the planet that even Voyager 2’s 1989 flyby couldn’t capture.
On the left is a composite of two images of Neptune’s rings taken by Voyager 2. The planet’s body is covered so that the probe can pick up more light from the icy giant’s faint rings.
“Wow, I’m in awe of those rings!” Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate, wrote about Webb’s Neptune images on Twitter Wednesday.
Webb’s new images show Neptune’s bright methane ice clouds reflecting sunlight, as well as a few galaxies against an inky expanse.
Neptune often appears bright blue in images due to the presence of methane in its atmosphere, as in the image below, taken by Hubble Space Telescope, which relies on visible wavelengths of light.
But because Webb picks up infrared light, Neptune doesn’t appear blue. Instead, it appears as a ghostly white planet. That’s because methane absorbs reddish and infrared light.
“In fact, the methane gas (in Neptune’s atmosphere) absorbs red and infrared light so strongly that the planet is quite dark at these near-infrared wavelengths, except where high-altitude clouds are present,” according to a statement from NASA.
The planet’s high-altitude methane ice clouds appear as brilliant, bright features because they reflect sunlight before it is absorbed by methane, according to NASA.
“More subtly, a thin line of brightness encircling the planet’s equator could be a visual signature of the global atmospheric circulation that drives Neptune’s winds and storms,” NASA added.
The above image shows seven of Neptune’s 14 known moons, including Galatea, Naiad, Thalassa, Despina, Larissa, and Proteus. The bright blue feature that looks like a star is actually Neptune’s largest moon, Triton, which outshines Neptune because it reflects more sunlight than the planet and its atmosphere.
Webb, often described as the successor to Hubble, launched on December 25, 2021, after more than two decades of development. Since that time, the $10 billion telescope has traveled more than 1 million miles from Earth and is now stationed in gravity-stable orbit to collect infrared light. By collecting infrared light, which is invisible to the human eye, Webb can cut through cosmic dust and see far into the past, to the first 400 million years after the Big Bang.