Sunspot on Far Side Is So Huge It's Changing How the Sun Vibrates

A sunspot on the far side of the sun is so large that it's changing the way sound moves through our star—and it could be revealed to us in days.

Sunspots are regions of the sun's atmosphere associated with intense magnetic fields that are so strong, they prevent some heat from the sun's interior from reaching the surface. This makes sunspots relatively cool, making them look like dark patches.

Sunspots are known sources of eruptions from our sun known as solar flares—bursts of radiation that travel to Earth at the speed of light. If they interact with the Earth's atmosphere, strong solar flares can cause disruption to radio communications.

These flares, along with other potentially disruptive eruptions known as coronal mass ejections (CMEs), are released whenever the intense magnetic fields associated with sunspots suddenly reorganize themselves.

The sun
A NASA Solar Dynamics Observatory (SDO) image of the sun in a blue hue seen on August 3, 2022. Scientists can take measurements to detect sunspots on the side of the sun that is facing away from Earth. NASA/SDO/AIA

Thus, scientists like to keep track of sunspots as they can be useful indicators of how active the sun is at a given moment. Flares, CMEs, and other solar phenomena that can affect Earth may be referred to as space weather.

Because the sun is a sphere, we can only directly see the sunspots that are facing us. However, it is also possible to detect sunspots on the back of the sun as well.

According to the website on Thursday: "There is a sunspot on the far side of the sun so big it is changing the way the sun vibrates."

The site added that due to the rotation of the sun, the sunspot is due to turn to face the Earth a few days from now.

Scientists can detect far-side sunspots and other hidden solar activity using a technique known as helioseismology.

Helioseismology is similar to regular seismology here on Earth. It works on the basis that sound waves, or vibrations, can travel through the interior of the sun and can be used to measure the star's internal structure and dynamics.

These sound waves can be measured by observing the light released from turbulent gas on the sun's surface. By observing changes to the wave patterns on the sun's visible side, it is possible to detect sunspots that are occurring on the other side, according to the European Space Agency (ESA).

Using this method, it's possible to produce an activity map of the entire sun every 12 hours.

"The detection of active regions on the far side of the Sun's surface is of great importance for space weather predictions," the U.S. National Solar Observatory (NSO) states on its website.

Currently, the National Oceanic and Atmospheric Administration's Space Weather Prediction Center (SWPC) does not have any significant space weather warnings or alerts in place.

Certain space weather events can not only affect radio communications but also energy grids and satellite operations.