Scientists studying Neptune’s temperature were in for a surprise recently. They discovered unusual temperature variations on the planet. Scientists had not anticipated such a dramatic temperature swing, with the planet becoming chilly during its summer season and then warming up at the south pole. In a statement, Michael Roman, the study’s lead author, said that the change was unexpected. “Since we have been observing Neptune during its early southern summer, we expected temperatures to be slowly growing warmer, not colder,” said Roman. These findings have taken researchers by surprise. They are yet to come up with an explanation for the phenomena.
The temperature drop could be the result of a number of factors, including the chemistry on the planet, weather patterns, and changes in the Sun. Astronomers using various ground-based telescopes to observe Neptune for the past 17 years saw this startling decline in the planet’s temperatures.
The study, named Sub-Seasonal Variation in Neptune’s Mid-Infrared Emission, was published in The Planetary Science Journal on April 11.
Like Earth, even Neptune has seasons, but they last much longer. On Neptune, one year is around 165 Earth years, and a season can last for about 40 years.
Scientists were keen to understand the seasonal patterns of Neptune. They looked at almost 100 thermal-infrared images of the planet in order to track the temperature changes during the summer solstice on the southern part of Neptune.
Through their observations, they could understand that the summer had arrived. But the thermal images of Neptune revealed that much of the planet had cooled, with temperatures dropping by 14 degrees Fahrenheit (8 degrees Celsius) between 2003 and 2018.
However, soon, the south pole suddenly warmed up. Between 2018 and 2020, the south pole saw a rise in temperature by 11 degrees Celsius. These changes were not expected by scientists studying the planet. The period under study is less than one season. Therefore, scientists had expected more gradual temperature changes.