On the afternoon of May 5, the National Space Weather Monitoring and Warning Center issued a solar flare information tip: At 14:01 Beijing time on May 5, 2024, a strong flare (X1.3 magnitude) erupted on the sun. The event occurred during daylight on the continent and the flare had an impact on the ionosphere over the continent.
It is expected that in the next three days, there is still a possibility of an M-class or even X-class flare or above.
What is a solar flare?
Solar flares are one of the most violently active phenomena on the Sun, with a cycle of about 11 years. The main observation characteristics are that the local area of the solar atmosphere suddenly brightens, often accompanied by the enhancement of electromagnetic radiation and particle emission in various energy bands, and the brightness rises rapidly and decreases slowly.
Although the lifespan of a solar flare is only between a few minutes and tens of minutes, the energy released is equivalent to the total energy of 100,000 or even a million strong volcanic eruptions, or the explosion of tens of billions of hydrogen bombs.
As a strong energy eruption on the surface of the sun, solar flares are divided into five levels: A, B, C, M, and X, of which A is the least energetic level.
The 25th solar cycle peak between January and October 2024 is the "solar maximum", which means that the Sun will reach the peak of its current activity cycle in 2024.
What are the effects of solar flares?
As the most typical solar eruption activity, a coronal mass ejection process can throw hundreds of millions of tons of solar material off the surface of the sun at a high speed of hundreds of kilometers per second, they carry the sun's strong magnetic field energy, once it hits the earth, it will cause a change in the direction and size of the geomagnetic field, that is, geomagnetic storm.
Professor Cheng Xin, deputy dean of the School of Astronomy and Space Science at Nanjing University, said that geomagnetic storms will cause voltage and current fluctuations in long-distance transmission systems, resulting in power outages or unstable power supply, changes in the attitude of satellites in orbit, affecting GPS signals, and causing navigation failures.
As early as February 2023, due to a geomagnetic storm, as many as 40 of the 49 Starlink satellites launched by SpaceX on February 3 fell into the atmosphere and were damaged.
In the face of geomagnetic storms, Cheng Xin said that accurate prediction of solar activity is crucial, but it can only be predicted a few days in advance. This gives us some warning time and operators can take steps to protect their infrastructure from the severe effects of solar storms, for example, by strategically shutting down the power grid, rerouting aircraft or satellite orbits, etc.
Geomagnetic storms are not all bad, such as the occurrence of aurora celestial phenomena, if the geomagnetic storm is particularly strong, and even further south it is possible to see the aurora.