Since 1989, when the NASA probe Voyager 2 passed by Neptune on its way out of the solar system, no spacecraft has made a stop at the planet. The furthest planet in our solar system, Neptune, is four times as wide as Earth. Astronomers were anxious to find out more information about the ice giant, and Voyager 2's observations whetted their appetites.
The James Webb Space Telescope viewed this distant planet on Wednesday September 21st,2022 with its mighty, gold-plated eye. Some of our best views of Neptune in the past 30 years have been made possible by the power of this infrared telescope, the biggest and most sophisticated telescope ever sent into space. In the past thirty years, numerous photographs of Neptune have been captured by both ground-based observatories and the Hubble Space Telescope. However, the Webb's observations of Neptune from July offer a previously unheard-before look at the planet in infrared light. In just a few minutes, the telescope was able to capture a close-up image of Neptune, and it only took another 20 minutes to capture a larger image, which showed not just the planet but also a vast number of galaxies that extended into space behind it. “It’s aesthetically fascinating to see those distant galaxies and get a sense for how small the ice giant appears,” said Klaus Pontoppidan, Webb project scientist at the Space Telescope Science Institute in Baltimore, which runs the Webb telescope.
The Neptune rings, which are most noticeable in the telescope's perspective because of the planet's orientation to Earth, are visible encircling it at a slight inclination. Astronomers will be able to measure the ring's reflectance using the Webb telescope, providing a unique perspective on this far-off spectacle. The dimensions and material of these thin bands, which are most likely formed of ice and other debris, may be revealed by new photos.
Brilliant lights can be seen all across the planet that soar high into the planet's skies and can last for days. These bright spots are thought to be methane ice clouds. "Nobody really knows what these things are,” said Patrick Irwin, a planetary physicist at Oxford University. “They seem to come and go, a bit like cirrus clouds on Earth.” The Webb telescope’s future observations could uncover how they form and what they are made of.
The 14 moons of Neptune are also visible in Webb pictures. The largest moon of the planet, Triton, is the brightest and is thought to have been drawn into the solar system by Neptune's gravity in the early solar system's history. Triton's frozen nitrogen surface makes it appear as a star in infrared photos, shining brighter than Neptune itself because methane makes the planet appear darker in infrared images. There isn't much to learn about Triton from this picture because NASA recently decided against sending a spacecraft to examine it. Future Webb observations, however, should provide some indication of the makeup of Triton's surface and may reveal variations that point to geological activity. These images of Neptune are just the latest in Webb’s tour of the solar system.
The observatory will be able to see far more of our solar system, including Saturn, Uranus, and even distant, frigid planets beyond Neptune, such the dwarf planet Pluto.
CC to : NASA,ESA