Berlin, August 24 (EFE).- A group of scientists succeeded, through the VLT telescope of the European Southern Observatory (ESO), located in northern Chile, to observe the dark spot on Neptune from Earth for the first time. as a smaller bright spot, according to a study published Thursday in Nature Astronomy.

This is the first time a dark spot has been observed on the planet with a terrestrial telescope. “This phenomenon, which is occasionally detected in the blue background of Neptune’s atmosphere, is a mystery to the astronomical community and these new results provide further clues to its nature and origin,” according to an ESO statement.

Great spots are a common phenomenon in the atmospheres of giant planets, such as the famous Great Red Spot on Jupiter, which is the most iconic. The dark spot was first discovered on Neptune in 1989 thanks to NASA’s Voyager 2 observations.

ESO remembers that this stain disappeared a few years later. “Since the first discovery of the dark spot, I’ve always wondered what these elusive short-lived dark events could be,” said Patrick Irwin, professor at the University of Oxford in England and the study’s principal investigator.

Irwin and his team used data from ESO’s VLT to rule out the possibility that the black spots were caused by a “cleanup” in the cloud.

Instead, new observations suggest that these dark spots may be caused by airborne particles that darken as ice and clouds mix in the atmosphere, and are located in a layer that sits beneath the main layer of visible Neptune’s haze.

ESO believes that reaching this conclusion will not be an easy task, as dark spots are not a permanent feature of Neptune’s atmosphere and the astronomical community has not been able to study them in sufficient detail until recently.

The opportunity arose after the NASA/ESA Hubble Space Telescope discovered several dark spots in Neptune’s atmosphere, including one in the Northern Hemisphere that was first detected in 2018. Irwin and his team got to work immediately, studying them from ground level with instruments. suitable for this challenging observation.

Using the VLT’s Multi Unit Spectroscopic Explorer (MUSE), scientists were able to divide the sunlight reflected from Neptune and its points into colors, or wavelengths, and obtain a 3D spectrum.

This way they can study the stain in greater detail, something that has not been done to date.

Because different wavelengths provide information at different depths in Neptune’s atmosphere, having a spectrum allowed the team to better determine how high up the dark spot is in the planet’s atmosphere. The spectrum also provides information about the chemical composition of different layers of the atmosphere, which provides clues as to why these spots appear dark.

There are also surprising results. “In the process, we discovered a rare type of deep glowing cloud that had never been identified before, even from space,” said Michael Wong, a co-author of the study and a researcher at the University of California (Berkeley, USA).

It appears as a bright spot right next to the larger main dark spot. The VLT data shows that the new “deep light cloud” is at the same atmospheric level as the main dark spot. This means that this is a completely new type of phenomenon compared to the previously observed methane ice small clouds at high altitudes.

ESO estimates that features such as these points can now be studied by the astronomical community from Earth. “At first, we could only detect these points by sending spacecraft, such as Voyager, there. Then we have the ability to view them remotely with Hubble. Finally, technology has advanced to allow it to be done from the surface of the earth,” Wong concluded.