The past few weeks have been unusually active in space weather. On May 10, a solar storm occurred that made auroras visible at latitudes rarely seen. Days later, on Tuesday, the Sun emitted the largest “flare” seen in this solar cycle so far.
In addition to solar flares, the Sun has also released matter in the form of coronal mass ejections (CME). It was precisely one of these events that caused the storm on May 10.
According to NASA, this solar storm was the strongest in two decades, and the space agency estimated that the auroras caused by it were the most intense in 500 years.
“We’ll be studying this event for years,” Teresa Nieves-Chinchilla, acting director of NASA’s Space Weather Analysis Office, said. “It will help us test the limits of our models and understanding of solar storms.”
During these hectic days, NASA closely monitored the Sun’s state. Meanwhile, on Earth, the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center warned of possible adverse phenomena from these events.
NASA’s Solar Dynamics Observatory (SDO) constantly monitors the Sun to alert scientists about events like those experienced in recent weeks. Launched in 2010, the SDO spacecraft serves as an important monitoring station for solar activity.
The SDO has provided mesmerizing images of solar activity, including several solar flares. Solar flares are bursts of electromagnetic radiation released by the Sun, traveling at the speed of light, making it impossible to predict their arrival on Earth.
The flare is visible at the top of the Sun, top center. The image was captured by blending 131 and 171 Angstrom light on May 2. | Image: NASA/SDO
Experts observed significant solar flares during the first days of May, with one (see image above) captured on May 2. In the days that followed, from May 3 to 9, 82 of these solar flares were recorded.
A solar flare seen on May 14 in the extreme ultraviolet spectrum. | Image: NASA/SDO
However, on Tuesday, NASA's observatory captured the most intense flare of Solar Cycle 25. This particular flare, seen in the image above, was classified as X8.7, the largest flare of the current solar cycle.
The solar flares seen on May 10 were accompanied by a massive coronal mass ejection (CME) that resulted in auroras. Unlike flares, CMEs expel charged particles, which travel more slowly but have a more intense effect on Earth.
Solar storms refer to the impact of these events on our planet’s atmosphere and surface. Flares can disrupt radio communications when they reach Earth, while ejections are typically associated with solar storms.
Auroras occur when charged particles ejected by the sun are deflected by Earth’s magnetosphere. Some particles are trapped and end up in the polar regions, where they collide with atmospheric gases, causing them to emit light and creating spectacular auroras.
Solar activity rises and falls in cycles lasting approximately 11 years, known as solar cycles. We’re currently approaching the peak of Solar Cycle 25. It’s not uncommon to experience increased solar activity or similar events during this time.
As of now, there haven’t been highly intense solar storms capable of causing severe issues with communication networks and electronic devices. However, experts are monitoring the situation closely. It’s better to be safe than sorry also when it comes to the Sun’s activity.
Image | NASA/SDO