Most of the World’s Observatories are Polluted with Light Pollution

Jakarta, CNNIndonesia —

Pollution excess light is called polluting the sky in most areas observatory aka the world’s main star binoculars. The end of the story of terrestrial astronomy?

This was discovered after a team of researchers from Italy, Chile and Spain compared light pollution at nearly 50 observatories, ranging from professional and largest to small and amateur observatories.

Reported Spacethe joint research team then applied models of how light travels through Earth’s atmosphere to night views captured by satellites.

The team measured that directly overhead or at the zenith there was less pollution, making it the darkest part of the night sky.

However, the researchers also looked at the average brightness at 30 degrees, which is the lowest point ground-based telescopes can reach, as well as the initial 10 degrees from the horizon.

The team also considered the average brightness of the sky and how artificial light comes from the night sky to brighten the land.

The scientists then compared these measurements to the light coming from the stars and the Milky Way, and to the natural brightness of the sky that is produced by a faint glow by Earth’s atmosphere called “airglow”.

By combining all of these factors, the research team was able to model how artificial light affects the night sky, and determine the night sky above the large observatory was much brighter than previously thought.

“Using the Garstang-Cinzano model applied to the Visible Infrared Imaging Radiometer Suite (VIIRS) 2021 light data from satellites, we compared 28 observatories that have telescopes with a 3-meter aperture, and several other observatories,” the experts wrote in the article. them in the journal Royal Astronomical Society.

As a result, at least seven of the 28 major observatories were defined as having peak brightness with light below the natural sky brightness threshold of 1 percent.

Worse, only one of the 28 major sites examined had light pollution below the 1 percent threshold at 30 degrees above the horizon.

The researchers also took into account the maximum allowable artificial brightness threshold for observatories of 10 percent set by the International Astronomical Union (IOU) in the 1970s.

However, there are still two-thirds of ground observatories that have a brightness threshold, according to the IOU criteria.

The least contaminated of all the sites featured in this study is a cottage in Namibia that houses several telescopes that are rented out to amateur astronomers.

This is known based on the report of a light pollution specialist physicist at the Universidade de Santiago de Compostela in Spain, Fabio Falchi.

“I was there recently and I can confirm that it is the least light polluted site I have ever seen,” he said in a statement.

“We should try to reduce light pollution levels at other sites to protect the future of ground-based astronomy.”

[Gambas:Video CNN]

(can/lth)

[Gambas:Video CNN]