According to comprehensive media reports, solar radio bursts are streams of electromagnetic radiation, mainly composed of radio waves, microwaves, ultraviolet rays, and X-rays. These radio waves will enter space together with superheated plasma jets (called coronal mass ejections), and released during a solar flare. In addition to radio bursts from some distant stars, solar radio bursts sometimes contain regularly repeating patterns called pseudoperiodic pulsations. This pulsation is similar to the beating pattern of a human heart.
The first “heartbeat” signal in the sun’s atmosphere repeats every 10 to 20 seconds, and scientists believe these signals come from an intermediate-level C-class solar flare 5,000 kilometers above the sun’s surface. A solar flare is one of the most powerful releases of energy, and a solar flare large enough to cause this effect would surpass Earth in size and dwarf Earth. The discovery, described as “unexpected,” said the “heartbeat” pattern is important for understanding how energy is released and dissipated in the sun’s atmosphere.
However, the origin of these repeating patterns, also known as “quasi-periodic pulsations,” has long been a mystery and a source of debate among solar physicists. In a study published Dec. 12, 2022, in the journal Nature Communications, solar radio astronomer Sijie Yu of the New Jersey Institute of Technology and colleagues analyzed the heartbeat signal contained in this C-class flare, which was detected in 2017. Erupted harmlessly from the sun on July 13, 2009.
Using data collected by the US Extended Owens Valley Solar Array (EOVSA) and NASA’s Solar Dynamics Observatory, scientists have managed to track down the exact location of the first signal, which they believe came from an electrical current more than 25,000 kilometers away Basal, formed through the eruptive core. This is because the magnetic field lines approach each other, break and then reconnect, causing the signal to be strongest here.
Additionally, the science team stumbled upon a secondary heartbeat signal, the second pulse, while analyzing the discovery. The secondary signal, which is weaker than the primary signal, beats every 30 to 60 seconds and originates from the entire current sheet, has never been observed before. “This repeating pattern is not unusual for solar radio bursts. But it is interesting that there is also a secondary source that we did not expect, located next to a stretched current sheet with similar pulses,” said one researcher. This is the first time such a signal has been detected.”
Investigations into the two “heartbeat-like” pulses continue. Overall, the discovery of these “heartbeat” signals can allow scientists to better understand the most powerful explosion phenomenon in the solar system, and hopefully help scientists better predict and respond to future solar activity.
