At the left, an enhanced-color image of Neptune from NASAs Hubble Space Telescope. At the right, that image is combined with data from NASAs James Webb Space Telescope to show auroras, represented by cyan coloring. NASA, ESA, CSA, STScI, Heidi Hammel (AURA), Henrik Melin (Northumbria University), Leigh Fletcher (University of Leicester), Stefanie Milam (NASA-GSFC)Earths beautiful northern and southern lights are the result of auroras: when high-energy charged particles from the sunhit gases in our upper atmosphere, making them glow in brilliant colors as they release energy from the collision. Auroras occur where Earths magnetic field crosses our planets atmosphere near the north and south poles.While scientists have previously observed auroras on Mars, Jupiter, Saturn and Uranus, NASAs James Webb Space Telescope (JWST) has finally spotted them on Neptune for the first time. The announcement is detailed in a study published Wednesday in the journal Nature Astronomy.If JWST was powerful enough to see the earliest galaxies in the universe, itd better be powerful enough to see things like aurorae on Neptune, study co-author Heidi Hammel, an astronomer at the Association of Universities for Research in Astronomy, tells the New York Times Robin George Andrews. And by golly, it was.Astronomers have been searching for auroral activity on Neptune, the most distant planet from the sun, since NASAs Voyager 2 spacecraft flew by it in 1989 and picked up tantalizing hints of the phenomenon, per a NASA statement.Neptune has always been elusive, James ODonoghue, a planetary scientist at the University of Reading in England and a co-author of the new study, tells the Associated Press Christina Larson. Weve been trying to see it again ever since [Voyager].In a newly released image featuring data from the Hubble and Webb space telescopes, cyan splotches represent Neptunes auroral activity. Unlike on Earth, the giant planets auroras occur at its geographic mid-latitudesthe equivalent auroras lighting up over South America. This is because Neptunes magnetic field has an odd orientation, which Voyager 2 revealed is tilted by 47 degrees relative to the planets axis of rotation.The detection offers a long-anticipated conclusion to astronomers search for auroral activity on the ice giant planet. Everyone is very excited to prove that its there, just like we thought, says Rosie Johnson, a space physics researcher at Aberystwyth University in Wales who wasnt involved in the study, to the New York Times.JWST collected the exciting data in June 2023 with its Near-Infrared Spectrographan instrument that can detect near-infrared wavelengths invisible to the human eye. The researchers analyzed the makeup and temperature of Neptunes upper atmosphere, detecting the presence of the trihydrogen cation (H3+), a molecule that can result from auroras.H3+ has a been a clear signifier on all the gas giantsJupiter, Saturn and Uranusof auroral activity, and we expected to see the same on Neptune as we investigated the planet over the years with the best ground-based facilities available, Hammel says in the statement. Only with a machine like Webb have we finally gotten that confirmation.The telescopes data on Neptune also revealed a new mystery: Since Voyager 2s flyby more than three decades ago, the temperature of the planets upper atmosphere has dropped by hundreds of degrees Fahrenheit. Since colder temperatures lead to fainter auroral activity, that likely explains why its been so difficult to spot Neptunes aurorasbut it doesnt explain why the ice giant cooled so dramatically.The answer to that might emerge with further research. Moving forward, astronomers aim to use JSWT to continue investigating Neptunes magnetic field over a full solar cycle of 11 years.Get the latest stories in your inbox every weekday.Filed Under: Astronomy, Discoveries, James Webb Space Telescope, NASA, Neptune, New Research, Outer Space, Planets, Solar System, Sun, telescope