Tag : MoS

Leicester (England): New research has revealed how temperatures in Neptune's atmosphere have unexpectedly fluctuated over the past two decades. The study was published in the journal, 'Planetary Science Journal'. Researchers used observations in thermal-infrared wavelengths beyond the visible light spectrum, effectively sensing heat emitted from the planet's atmosphere. They combined all existing thermal infrared images of Neptune gathered from multiple observatories over almost two decades. These include the European Southern Observatory's Very Large Telescope and Gemini South telescope in Chile, together with the Subaru Telescope, Keck Telescope, and the Gemini North telescope, all in Hawai'i, and spectra from NASA's Spitzer Space Telescope. By analysing the data, the researchers were able to reveal a more complete picture of trends in Neptune's temperatures than ever before. But to the researchers' surprise, these collective datasets show a decline in Neptune's thermal brightness since reliable thermal imaging began in 2003, indicating that globally-averaged temperatures in Neptune's stratosphere -- the layer of the atmosphere just above its active weather layer -- have dropped by roughly 8 degrees Celsius (14 degrees Fahrenheit) between 2003 and 2018. Dr Michael Roman, Postdoctoral Research Associate at the University of Leicester and lead author of the paper, said, "This change was unexpected. Since we have been observing Neptune during its early southern summer, we would expect temperatures to be slowly growing warmer, not colder." Neptune has an axial tilt, and so it experiences seasons, just like Earth. However, given its great distance from the Sun, Neptune takes over 165 years to complete an orbit around its host star, ...