Astronomers tell it in the magazine Nature Astronomy. They are radio observations of an extraordinary display 40,000 kilometers above a sunspot. The aurora discovered above the Sun draws the attention of scientists.
The new radio emission shares characteristics with auroral radio emissions from other planetary magnetospheres. Some surround Earth, Jupiter and Saturn, and certain low-mass stars.
cosmic lighthouse
«It is a peculiar type of long-duration polarized radio bursts that emanate from a sunspot. “They persist for more than a week,” they said in a statement. “This is quite different from typical transient solar radio bursts that typically last minutes or hours. It’s an exciting discovery. “It has the potential to alter our understanding of stellar magnetic processes.”
Auroral lights occur when solar activities disturb Earth’s magnetosphere. It facilitates the precipitation of charged particles in the polar region of the Earth where the magnetic field converges. It is something not seen before in these circumstances.
«It is different from the auroras on Earth. These sunspot auroral emissions occur at frequencies ranging from hundreds of thousands of kHz to approximately 1 million kHz. “The magnetic field of sunspots is thousands of times stronger than that of the Earth.” The “sunspot radioaurora” is believed to exhibit rotational modulation synchronized with solar rotation. It produces what they describe as a “cosmic lighthouse effect.”
First detection
“As the sunspot passes through the solar disk, it creates a rotating beam of radio light, similar to the aurora. It is the first detection of its kind. “Some of the previously recorded solar explosions could be examples of this emission and we didn’t know it.”
Solar radio emissions are weaker. They are compared to stellar auroral emissions observed in the past. They could be the sources of certain radio bursts observed in various stellar environments.
The aurora discovered above the Sun can help solve some riddles. «We are beginning to solve the puzzle. We want to know how energetic particles and magnetic fields interact in star spots. “Not only in our own Sun but also in stars far beyond our solar system.”
