What is the weather at night? Venus? Scientists are finally finding out.
Just one planet away from us, Venus is relatively close to Earth, and we have studied it for a long time, with the first Venus probe to reach the planet in 1978. However, scientists knew very little about the night weather on Venus. … That is, until now.
In a new study, scientists have developed a new way to use infrared sensors on Japan’s Venus climate orbiter. Akatsuki, a probe that entered orbit around Venus in 2015 to finally figure out what the weather is like on the planet at night. These sensors have detected night clouds and some strange patterns of wind circulation.
Connected: Photos of Venus, the mysterious planet next door
Like Earth, Venus is in the “habitable zone” of our Sun, has a hard surface and an atmosphere in which there is weather. To understand the planet’s weather, researchers study the movement of clouds in infrared light. However, while Atmosphere of Venus rotates fast, the planet itself has the slowest rotation of all the major planets in our solar system, which means that day and night last for quite a long time – about 120 earth days each…
Until now, only the weather on the “day side” of Venus could be easily observed, because even in the infrared range it is difficult to get a clear picture of the night side of Venus. Infrared observations of the “night side” of Venus were made, but these studies were unable to clearly show the night weather on the planet.
To explore this mysterious aspect of our neighboring planet, researchers turned to Akatsuki, the first Japanese probe to ever orbit another planet. Designed to monitor Venus and its weather, the probe has an infrared imager that does not need sunlight to “see.” Despite this design, the thermal imager was unable to capture detailed observations of the night side of Venus. However, using a new analytical method for processing data obtained with a thermal imager, the researchers could indirectly “see” the elusive night weather of Venus.
“Small-scale cloud structures in live images are dim and often indistinguishable from background noise,” says co-author Takeshi Imamura, professor at the Graduate School of Frontier Sciences at the University of Tokyo. said in a statement…
“We needed to suppress noise to see the details,” he said. “In astronomy and planetary science, it is customary to combine images for this, since real objects in a stack of similar images quickly hide the noise. However, Venus is a special case because the entire weather system rotates very quickly, so we had to compensate for this movement, known as super rotation, to highlight interesting formations to study. “
Using this new analytical method, the team probed the planet’s northeast winds at night and found something rather strange.
“Surprisingly, they are running in the opposite direction from their daytime counterparts,” Imamura said. “Such a dramatic change cannot happen without significant consequences. This observation could help us build more accurate models of the Venusian weather system, which will hopefully address some of the long-standing, unanswered questions about Venus’s weather and possibly Earth’s weather too. ”
Using this new method, the researchers believe future research may reveal new details about the weather on other planets like Mars or even our own planet Earth, according to the researchers.
While this work leverages existing technology in orbit around Venus, three new missions will soon appear on the planet that will continue to expand our understanding of Venus and its climate. NASA recently announced two new missions to Venus, dubbed DAVINCI + and VERITAS, and the European Space Agency said it would launch EnVision mission to the planet. Three spacecraft will be launched at the end of this decade – in the early 2030s.
This work was described in a study published July 21. in the journal Nature.
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