NASA said the sun was seen 'smiling' in a newly released satellite image

• The sun can be seen 'smiling' in a new image from NASA's Solar Dynamics Observatory.
• The "eyes" and "mouth" on the surface of the sun are coronal holes.

NASA released a new satellite image of the sun this week, and it appears to have a big smile on its face.

The photo was captured by NASA's Solar Dynamics Observatory, a program working to understand the changes in the Sun's radiation output.

Sharing the snap on Twitter, @NASASun wrote: "Say cheese! Today, NASA's Solar Dynamics Observatory caught the Sun "smiling."

"Seen in ultraviolet light, these dark patches on the Sun are known as coronal holes and are regions where fast solar wind gushes out into space."

The outer layer of the sun is known as the "corona," and darker areas seen on satellite images are the coronal holes

"They're regions on the sun where the magnetic field is open to interplanetary space, sending solar material speeding out in a high-speed stream of solar wind," NASA has previously explained.

They show up as dark spots, or in this case, facial features, because they typically boast lower temperatures and densities than their surroundings, leading to an empty look.

Coronal holes can occur at any time but can't be seen by the naked eye or a home telescope, they're only visible in ultraviolet and X-ray light, LiveScience reported.

Twitter users responded to the photo with their own comparisons, some better than others. One user likened the picture to the iconic Teletubbies sun. Another put a Halloween spell on it, turning the sun into a pumpkin.

It's not all happy news, though, Spaceweather.com explains that the holes could be a sign that geomagnetic storms could hit Earth's magnetic field on October 29 or 30.