The sun emits light with higher energy than thought possible

Scientists have discovered that the Sun emits light of higher energy than previously thought. Using an unusual type of telescope, the High Altitude Water Observatory (HAWC), researchers have detected gamma rays with energies of more than 1 teraelectronvolt (TeV), which is at least five times higher than previously known energies.

The Sun emits light in a wide range of energies, from infrared to visible and ultraviolet. It has been thought that the Sun can generate gamma rays, the most energetic form of electromagnetic radiation, by interacting with cosmic rays from distant sources, but it was thought that these gamma rays rarely reach Earth and therefore go undetected.

However, in 2011, NASA’s Fermi gamma-ray telescope managed to detect these elusive gamma rays. Over the years, it has been observed that the Sun produces about seven times more gamma rays than originally predicted, with energies as high as 200 gigaelectronvolts (GeV) – the upper limit of Fermi’s capabilities. To study this phenomenon in more depth, scientists turned to the HAWC instrument, known for its sensitivity beyond the Fermi limit.

Unlike conventional telescopes, HAWC is a series of 300 large tanks, each filled with 200 tons of water. When gamma rays interact with molecules in the Earth’s atmosphere, they produce a cascade of lower energy particles that then interact with the water molecules in the tanks. Sensitive instruments track these interactions, allowing scientists to calculate the energy of the original gamma rays.

By analyzing HAWC data collected between 2015 and 2021, scientists made a surprising discovery: the Sun produces gamma rays with energies much higher than those detected by Fermi. Some of these gamma rays reached energies on the order of TeV, with individual bursts nearly reaching 10 TeV.

“At first we were sure we had made a mistake when, after analyzing six years of data, we saw such an excess of gamma rays. We could not believe that the Sun could emit such energy,” shared Mehr Un Nisa, corresponding author of the study.

The huge amount of data collected over these six years has confirmed that high-energy gamma rays from the Sun do exist. However, their exact mechanism remains a mystery. The research team intends to continue studying how the Sun reaches such high energies and whether the Sun’s magnetic field plays a role in this phenomenon.

This groundbreaking study, which sheds new light on the Sun’s gamma ray emission, was published in the journal Physical Review Letters.

Notify of

Inline Feedbacks
View all comments
Would love your thoughts, please comment.x