A powerful X2-class eruption on the Sun, considered the strongest in recent years, was recorded on Friday (17). The event, followed by a solar storm lasting more than an hour, caused disruptions to radio services on Earth’s sunlit side.
Also known as a “flare”, a solar flare is a sudden explosion that occurs on the surface of the star, caused by changes in the star’s magnetic field. The most recent arose from a sunspot called Active Region 3229, according to Spaceweather.com.
Images of the massive solar flare were captured by NASA’s Solar Dynamics Observatory probe, which is on a mission to observe the Sun. It appears at 44 seconds of the video below, which gathers records of more than 30 explosions of this type and 28 coronal mass ejections (CMEs) that occurred last week.
Happy #SunDay! This week’s space weather report includes 36 notable solar flares, 28 coronal mass ejections, and no geomagnetic storms. This video of the Sun from NASA’s Solar Dynamics Observatory includes an X-class solar flare (the most powerful kind of flare) at 0:44. pic.twitter.com/u7YEyGMhND
— NASA Sun & Space (@NASASun) February 19, 2023
The eruption triggered a CME that traveled at about 1.6 million km/h towards Earth, making the aurora borealis more intense, colorful and visible as far south as the southern states of Idaho and New York, in the United States, on the day following the occurrence. In addition to communications, solar storms can affect power systems, causing damage to some equipment.
How are solar flares classified?
According to the American space agency, solar eruptions are classified with letters and numbers that represent the intensity of each one of them. Class A flares are the weakest, while class B, C and M are rated moderate and class X, like last week’s, are the most powerful.
The numbers accompanying the letters represent the magnitude of the event — the higher the number, the stronger the explosion. In this eruption in question, the classification given by NASA was X2.2, one of the largest recorded in Cycle 25 of the Sun, which can also bring problems for navigation systems and risks for spacecraft and astronauts.