The James Webb Space Telescope has delivered new images of the planet Neptune and its rings, which provide valuable insights into its atmosphere, NASA announced on Wednesday. Astronomers have not had such a clear view of the most distant planet in the solar system since the brief and unique passage of a probe, Voyager 2, in the vicinity of this icy giant in 1989.
The telescope’s infrared vision provides a new way to analyze its atmosphere, said Mark McCaughrean, science and exploration adviser at the European Space Agency (ESA).
The telescope eliminates all the glare due to the reflection of the sun on the surface of Neptune and the light pollution of its environment, in order “to begin to guess the atmospheric composition” of the planet, told AFP this astronomer who worked for more than 20 years on the James Webb project.
Neptune had a bluish appearance in images taken in the visible waveband by the Hubble telescope, due to the presence of methane in its atmosphere.
With James Webb’s NIRCam instrument, which works in the near infrared, the planet takes on a colorized hue in a grayish white. The image also shows “strange light” at one of Neptune’s poles, NASA said in a statement.
The telescope also captured images of seven of the planet’s fourteen known moons. And in particular of Triton, which resembles by its brilliance a small star. Larger than the dwarf planet Pluto, it also appears brighter than Neptune because of the reflection of sunlight off its icy surface.
Astronomers looking for planets outside our solar system have found that those like Neptune or Uranus are the most common.
“The ability to observe these up close will make it easier to observe others (icy giants) orbiting stars other than our Sun,” McCaughrean said.
In service since last July, the James Webb is the most powerful space telescope ever deployed. It will enable a kind of astronomy “that was unthinkable even five years ago,” McCaughrean said.