Neptune is one of the most mysterious planets in the solar system. He was visited by a single spacecraft – on August 25, 1989, Voyager 2 flew past him.
It’s a bit of a shame not only because of our home planetary backyard research. We recently celebrated 5,000 known planets outside the solar system. As it turns out, planets similar to Neptune or slightly smaller (but larger than Earth) are the most common in the universe.
In the case of Neptune’s research, we are still referring primarily to research from and from Earth. It is monitored by terrestrial and space telescopes – JWST will soon focus on it.
It takes Neptune 165 years to orbit the sun. For research on seasonal changes, we need data over a longer period of time. Scientists have now put together observations [odkaz na studii] from the Middle Infrared from 2003 to 2020. These were data from various instruments on the VLT telescopes of the European Southern Observatory in Chile, the Gemini, Subaru telescopes (he starred in the film Watch!), the Keck telescope and the no longer functioning Spitzer space telescope.
Most of Neptune has gradually cooled over the last twenty years
Like on Earth and Neptune, the seasons alternate as the planet orbits the Sun. The difference, however, is that with a cycle of 165 years, Neptune lasts about 40 years each year.
Summer has risen in the southern hemisphere of Neptune since 2005, so astronomers expected temperatures to rise slowly. In fact, they were declining!
The data showed that despite the arrival of summer in the southern hemisphere, most of the planet had gradually cooled over the past twenty years. The average global temperature in Neptune fell by 8 ° C between 2003 and 2018.
However, in the last three years of observation, astronomers were surprised by the dramatic warming of the planet’s south pole, when the temperature rose by 11 ° C. And although the warm polar vortex on Neptune has been known for many years, such rapid warming has not yet been observed on the planet.
Since the temperature changes on Neptune were unexpected, astronomers do not yet know what is causing them. They could be related to changes in the chemical composition of Neptune’s atmosphere, the current course of the weather, or even the solar cycle.