These dark patches, known as sunspots, are of interest to astronomers because they tend to be located where the sun’s magnetic fields are particularly strong.

These magnetic fields are constantly moving and twisting. When they get too contorted, these magnetic fields can suddenly and violently realign themselves, releasing vast amounts of energy and charged particles as they do so.

We refer to these energetic eruptions as solar flares and coronal mass ejections (CMEs), which can transfer some of the sun’s energy to Earth and interfere with our planet’s own magnetic field and atmosphere.

If they’re strong enough, solar flares and CMEs can interfere with electrical systems as well as satellites, navigation systems, and radio communications.

Earlier this year, a CME was credited with causing a number of SpaceX satellites to fall out of orbit after it caused them to experience higher-than-expected atmospheric drag.

On the other hand, CMEs can also cause particularly dazzling auroras, also called the Northern and Southern Lights, in places where they might not usually occur.

In short, space weather is important to track, especially as the sun is now entering a period of increasing activity as part of its 11-year repeating solar cycle. The current cycle, Solar Cycle 25, is winding up.

Scientists can tell how active the sun is by looking at how many sunspots there are. The more sun spots we can see, the more active the sun is. Sunspots are dark because the intense magnetic fields prevent some heat within the sun reaching the surface.

This week, astronomers have spotted a swarm of sunspots bundled close together in a region of the sun facing towards Earth. They’ve been a source of heightened solar activity for days, spitting out flares and radiation.

The sunspots have been split into groups called 2993, 2994, 2995, and 2996—the last of which has come into view more recently. One astrophotographer said they could “swallow the whole Earth.”

Terrifyingly, despite the colossal size of the sunspot groups which cover hundreds of millions of square miles, solar physicist Dean Pesnell at NASA’s Goddard Space Flight Center told Live Science that they were merely “middling in size.”

He added: “I’m sure we shall see larger [active regions] over the next few years.”

Last week, experts told Newsweek that the current solar cycle appears to be more active than predicted.