For years, strange beams of tremendous energy have been coming from the sun. We were unable to figure it out, but a recently built new piece of equipment could change everything.
The sun is much stranger than we thought. We thought we already knew our star very well, but we were so wrong.”
– quotes Phys.org Science Portal Mehr On-Nissa, a researcher at the University of Michigan who studied the strange behavior of the sun.
A new study published in the journal Physical Review Letters describes how the highest-energy light from the Sun has been detected so far. The international research team behind this discovery also found that the sun emits much more gamma rays than previously thought.
Although this high-energy light does not reach the Earth’s surface, the gamma rays create signals that can be detected by a special research instrument, the High Altitude Water Cherenkov Observatory (HAWC) in Mexico.
The miracle telescope that works on water
One of the great advantages of HAWC is that, unlike other telescopes, it operates around the clock, so it can observe rays that pass unnoticed by other instruments.
“We now have surveillance technologies we could only have dreamed of years ago,” said Nessa. HAWC is not built like traditional binoculars; An intricate network of 300 tanks, each filled with 200 tons of distilled water. The reservoir network is located on top of an inactive Mexican volcano at an altitude of 4,100 metres.
Gamma rays strike the atmosphere and cause molecular explosions invisible to the naked eye. During the process, new molecules are created that interact with the water in the reagent tanks. As a result, so-called Cherenkov radiation is produced, which the telescope system’s instruments can detect.
This powerful gamma ray has never been detected before
Nisa and her colleagues began collecting data in 2015. In 2021, the team has already collected enough information to begin investigating solar gamma radiation with sufficient precision. The results obtained surprised even well-known researchers.
After combing through six years of data, we got so much excess radiation that we thought we might be on to something. We could not believe that the sun was sending rays of high energy towards us. But this is the situation. said Nessa.
The sun emits light of different energies, some rays have a higher energy level, while others have a lower energy level. Through nuclear reactions our star produces a lot of visible light, this is the well-known sunlight, which carries 1 electron volt of energy.
The gamma rays detected by NISA and her colleagues have an energy of about one trillion electron volts.
Not only was the high energy level surprising, but scientists also found a lot of these rays.
They already guessed we were only scratching the surface
Already in 1990, science was of the opinion that the Sun is capable of creating gamma rays. This requires that high-energy cosmic rays (particles accelerated by a black hole or a supernova explosion) collide with the Sun and split into protons. However, scientists still consider it unlikely that gamma rays will ever reach Earth, at least in large numbers.
However, at the time, no instrument was capable of detecting high-energy gamma rays. Gamma rays with energies greater than 1 billion electron volts were first detected by scientists in 2011 using the NASA-operated Fermi telescope operating in the gamma band.
Over the next few years, the Fermi mission showed that not only could these rays be high-energy, but that there were about seven times more of them than astronomers originally thought, and that there were still more gamma rays of amazing energy. Discover.
At the same time, there is a limit to the size and performance of detectors operating in space. For example, the Fermi telescope could not detect gamma rays larger than 200 billion electron volts. This is why ground-based observatories such as HAWC have come in handy.
There are currently more questions than answers
The HAWC collaboration includes more than 30 institutions in North America, Europe and Asia, and a large part of this has been contributed by nearly 100 authors Stady to prepare.
At this point, the research raises more questions than it answers. It is not known, for example, how massive, high-energy gamma rays are formed, what size and what role the Sun’s magnetic fields play in this phenomenon.
