[Epoch Times, April 16, 2022](The Epoch Times reporter Di Rui compiled and reported) With the improvement of telescope observation capabilities, scientists recently discovered that the most distant planet in the solar system, Neptune, has an abnormal temperature change.
After Pluto was downgraded to a dwarf planet by scientists, there are now only eight planets left in the solar system. According to their distance from the sun, from near to far, they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Neptune is the outermost planet, and its orbit around the sun is 30 times the radius of Earth’s orbit around the sun. That makes Neptune a long time to go around the sun: about 165 years. That means a season on Neptune lasts more than forty Earth years.
Right now, it’s summer in Neptune’s southern hemisphere. It stands to reason that the temperature in the southern hemisphere should be in a gradual upward trend, but scientists have found the phenomenon of cooling, which is puzzling.
A study that combined 17 years of observations from several ground-based telescopes found that between 2003 and 2018, Neptune’s global average temperature dropped by about 8 degrees Celsius.
Michael Roman, a planetary scientist at the University of Leicester in the UK, said: “This change was unexpected, as we started observing in early summer in the southern hemisphere of Neptune, where we would expect gradual warming. , instead of getting cold.”
Because Neptune is so far away, it is not easy to detect the temperature there. Infrared observation technology used by some telescopes in recent years can sense the infrared rays emitted by distant stars.
During the observation period, in addition to the above-mentioned abnormal cooling, the researchers also found that in only two years from 2018 to 2020, Neptune’s south pole warmed sharply, where the temperature increased rapidly by about 11 degrees Celsius.
This shows that the temperature of Neptune’s atmosphere fluctuates greatly during the same season. The researchers don’t know the exact reason behind this, but have made some speculations, such as it may be related to changes in the chemical composition of the atmosphere.
“While methane absorbs sunlight and warms the atmosphere, methane photochemically produces hydrocarbons, primarily ethane and acetylene, which emit powerful infrared light, cooling the stratosphere,” the study wrote. The balance between photochemical) cooling changes with the photochemical hydrocarbons.”
Another speculation is that it may be related to a type of “dark vortices” on Neptune, which remains a mystery to this day. The researchers also considered that it may be related to the solar flux (Solar flux), that is, changes in solar radiation may trigger changes in photochemical reactions in Neptune’s atmosphere, which in turn lead to changes in atmospheric temperature.
Roman said that scientists still know very little about Neptune. The discovery of these strange phenomena shows that Neptune’s atmosphere has a complex mechanism. He hopes that future research will gradually reveal its mystery.
The study was published April 11 in The Planetary Science Journal. ◇
Responsible editor: Ye Ziming#