The sun emits high-energy light from an unknown source.

The sun appears to shine evenly in our sky. But researchers report today that they’ve recorded an inexplicably bright light from our star.

According to the latest estimates, our Sun could reach its maximum activity in about a year. More and more large sunspots and frequent solar flares confirm this. but what Researchers from Michigan State University (USA) report now, has nothing to do with this activity cycle. By the way, the discovery was made in a fairly quiet phase of our star. However, it is the most energetic radiation ever recorded by the Sun.

A tool to reveal the secrets of sunlight

The physicists found it in data collected by the High Altitude Water Cherenkov Experiment (HAWC, Mexico) gamma-ray observatory.

An observatory with the advantage of operating 24 hours a day, not just at night. Between 2014 and 2021, researchers detected emissions from our sun ranging from 0.5 to 2.6 teraelectronvolts (TeV) – peaking at 10 TeV – roughly equivalent to one trillion electronvolts. For comparison: the energy of visible light that our star sends us is about 1 trillion times higher.

That’s still far less than the most intense gamma-ray source ever seen in the universe, at about 450 TeV. But there is still much more to the sun than astronomers thought possible.

Bright light produced by interactions with cosmic rays?

To explain this phenomenon, researchers cite interactions between galactic cosmic rays in the giga-electronvolt (GeV) range—generated by black holes or supernova explosions of stars—and atomic nuclei in the solar atmosphere. They theoretically researched it in the 1990s. However, they never imagined that they would make it to Earth. Then the Fermi mission exposed them. in larger quantities than expected.

Physicists at the time suspected the existence of high-energy gamma rays. Especially when the sun is in its calm phase. This has now been confirmed by data from the HAWC Observatory. It remains to be shown how these energies can be realized. and whether the magnetic fields prevailing within our star play a role.

Michigan State University physicists were part of an international collaboration that discovered high-energy light coming from the sun.https://t.co/Yf5wpK7Juh pic.twitter.com/LbUIInTRGx

– MSU College of Natural Sciences (MSUNatSci) August 3, 2023

Editor: Futura, by Natalie Meyer

Cover image: © filins, Adobe Stock – Astronomers from Michigan State University (USA) report that they have recorded high-energy gamma rays from our sun.

2. Photo: © Jordan A. Goodman, Wikimedia Commons