When the words ring and space are associated, one immediately thinks of Saturn. But another planet in our solar system is also surrounded by several coronas. Unpublished images of the planet Neptune and its rings have thus been captured by the James Webb space telescope. These pictures also provide valuable information on its atmosphere explained NASA 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 glare due to the sun’s reflection off Neptune’s surface and light pollution from its surroundings, so “to begin to guess the atmospheric composition” of the planet, said this astronomer who worked 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 picture also shows “a strange light“at one of Neptune’s poles, the US space agency also 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’s going to allow a kind of astronomy”which was unthinkable even five years ago “, Mr. McCaughrean said.