James Webb’s clearest image of Neptune’s rings, As well-known as Saturn’s rings are, they are not unique in the solar system. Even though Neptune’s rings are often quite dim and hard to make out, a new image from the James Webb Space Telescope shows them in stunning clarity.
To add to a recent Webb image that revealed Jupiter’s very invisible rings, this one shows that Webb may be used to examine targets in our own solar system as well as those in the distant universe.
Webb’s Near-Infrared Camera, or NIRCam, which detects light between 0.6 and 5 microns in wavelength, took the picture of Neptune (via NASA). Neptune’s distinctive blue hue, created by methane in its atmosphere, is not visible in the infrared as seen by this sensor.
Infrared light is absorbed by the methane, making those areas appear darker. The planet’s methane ice clouds, on the other hand, are visible as brighter areas throughout its surface because they reflect sunlight.
It’s not often that we get such a clear view of Neptune because it’s one of the solar system’s more distant planets, 30 times farther from the sun than Earth is. That’s why this picture is so crucial for science.
This stunning photograph also conveys important information about Neptune. Several of the planet’s moons are visible, including the planet’s biggest moon, Triton. Although Neptune has 14 known moons, this one moon accounts for 99.5 percent of the mass in orbit around the planet. The planet has a peculiar spherical shape and rotates in the opposite direction of Neptune. Above and to the left of Neptune is an extremely brilliant dot, which is Triton.
You can view Neptune’s smaller moons, such as Galatea, Naiad, Thalassa, Larissa, Despina, and Proteus if you look closely enough.
The movement of Neptune’s atmosphere is also assumed to be responsible for what NASA calls a “thin line of brightness” around the equator of the planet in the image. Hydrogen, helium, and methane predominate in the planet’s thick atmosphere, which is split into an upper and lower layer.
The clouds in this atmosphere are constantly shifting and evolving in response to the winds and storms that characterize the planet’s climate. The brilliant band forms around the equator because gases in the atmosphere warm and sink, causing them to emit more infrared light.
The north pole of Neptune is another remarkable feature that lies just out of camera range. This pole is difficult to view due to the planet’s orbit, but NASA notes that there appears to be some brightness emanating from there in the image, which they find intriguing. A cloud-encircling vortex can be seen at the planet’s south pole.