Webb Telescope Captures Neptune’s Beauty
The wide-field version of Webb’s NIRCam image of Neptune. Credit...NASA, ESA, CSA, STScI
Since 1989, when the NASA probe Voyager 2 flew by on its way out of the solar system, no spacecraft has visited Neptune. Neptune, which is four times the size of Earth, is our solar system's most distant planet. The observations made by Voyager 2 whet the appetites of astronomers eager to learn more about the ice giant.
The James Webb Space Telescope peered into this remote world with its powerful gold-plated eye. The power of this infrared machine, the largest and most advanced telescope ever launched into space, has given us some of the best views of Neptune in 30 years.
"I've been looking forward to seeing these images of Neptune for a long time," said Heidi Hammel, a NASA interdisciplinary scientist for the Webb telescope and Vice President for Science at the Association of Universities for Research in Astronomy in Washington, D.C. "I'm overjoyed that it worked."
Neptune with its rings and several of its moons clearly visible, as captured by the James Webb Space Telescope’s Near Infrared Camera. Credit...NASA, ESA, CSA, STScI
New images of Neptune by the James Webb Space Telescope provide an unprecedented glimpse at the ice giant in infrared light. It took just a few minutes for the telescope to image Neptune close up, and another 20 to take a wider view, revealing not just the planet but myriad galaxies behind it. "It's aesthetically fascinating to see those distant galaxies," said Klaus Pontoppidan, Webb project scientist.
The rings of Neptune are most visible in the telescope's view, seen encircling the planet at a slight tilt due to its orientation to Earth. Astronomers will be able to measure the reflectivity of the rings using the Webb telescope, providing unprecedented insight into this remote spectacle. New images could shed light on the size and composition of these thin bands, which are most likely composed of ice and other debris.
"The ring system was completely perplexing to me," Dr. Hammel said. "I haven't seen anything like it since the Voyager encounter in 1989." It just jumps out at you."
"Nobody really knows what these things are," said Patrick Irwin, a planetary physicist at Oxford University.
Seven of Neptune's 14 moons are also visible in Webb images. Triton, the planet's largest moon, is the brightest, and scientists believe it was captured by Neptune's gravity early in the solar system's history. Triton's frozen nitrogen surface shines like a star in infrared images, brighter than Neptune itself, because methane dims the planet in infrared light. NASA recently declined to send a mission to study Triton, and this image doesn't reveal much about it. However, future Webb observations should provide clues about the composition of Triton's surface, as well as changes indicating geological activity.
The wide-field version of Webb’s NIRCam image of Neptune. Credit...NASA, ESA, CSA, STScI
Dr. Hammel described Triton as a "geologically active world." "Cryovolcanoes erupted as Voyager 2 flew by." As a result, there is a chance that the surface chemistry will change over time. We'll be looking for it."
NASA seems to be close to getting more and more clear pictures of the other planets in our Solar System using the Webb Space Telescope. I am amazed by Neptune’s beauty. It looks so close yet so far..
