Neptune orbits 2.8 billion miles from Earth and it takes 165 years to orbit the Sun.
During 2003 and 2018 average temperatures in Neptune's stratosphere, decreased by 14 degrees Fahrenheit.
And between 2018 and 2020, stratospheric temperatures in the South Pole suddenly increase by a whopping 20 degrees.
Something strange happening
The dramatic changes are unexpected because they're happening amid a profoundly long Neptunian season.
Neptune rotates on a tilted axis and thus has significant seasonal changes,
Scientists expected such extreme temperature changes to happen during different seasons, explained Glenn Orton, a planetary scientist at NASA's Jet Propulsion Laboratory.
Reasons for this changes
Reason 1It's possible the sun's 11-year activity cycles may be reason to temperature changes in Neptune's stratosphere.
Reason 2Chemical changes in the planet's hydrogen-rich atmosphere may lead to these abrupt changes.
For better understanding, we need to see better distant Neptune.
For this we need James Webb Space Telescope the most powerful space telescope ever built.
JWST expected to start observing the cosmos in June. It operates at extremely cold temperatures i.e. -447 degrees Fahrenheit.
Which makes the instrument more sensitive to changes in very cold places like Neptune.