By operating Nasa's James Webb Space Telescope to capture new images, astronomers have been able to discover surprising details about Saturn's atmosphere.
In the image, Saturn is seemingly extremely dark, which is because of the methane gas that absorbs nearly all of the solar radiation from the Sun. On the other hand, the rings remain quite bright, forming the “unusual appearance” of the planet in this photo.
Three of Saturn's moons, Dione, Enceladus and Tethys, can be seen on the left side. Conversely, the Cassini division, the largest gap in Saturn's ring system, the Encke gap, and rings A, B, C and F are visible on the right side.
For the very first time, near-infrared observations were made of the ringed planet using the very sensitive Webb telescope, according to Nasa. With 1.5 million kilometres from the Earth, this telescope observes the universe with wavelengths of light longer than those of other space telescopes.
Nasa captured the image using Webb's NIRCam, which is Webb's Near-Infrared Camera, as part of a program to examine Saturn in deep exposures. These exposures test Webb's ability to detect faint moons and gain insights into Saturn's systems.
Surprisingly, “the large, diffuse structures in the northern hemisphere do not follow the planet's lines of latitude, so this image is lacking the familiar striped appearance that is typically seen from Saturn's deeper atmospheric layers,” according to Nasa.
As per the reports made by Nasa, the contrast in looks between the northern and southern poles of Saturn appears to be as expected. The northern region is facing summer, whereas the southern hemisphere is leaving the winter darkness. However, according to Nasa, the northern hemisphere has a slightly darker-than-usual appearance which is likely to be caused by “an unknown seasonal process affecting polar aerosols in particular.”
The brightening towards the edge of Saturn's disk may be caused by emissions in the planet's ionosphere, high-altitude methane fluorescence (the process of producing light after absorbing light), or both.
The Webb telescope recently discovered a record-breaking water plume spewing from Saturn's moon Enceladus, which feeds Saturn's hazy E ring, as reported by Nasa. This latest detailed image was taken just a few weeks after that discovery.
These fresh Webb telescope findings "are just a hint at what this observatory will add to Saturn's story in the coming years," according to Nasa, "as the science team delves deeply into the data to prepare peer-reviewed results."
