X-flare yesterday, aurora alert this weekend

The biggest solar flares are known as X-flares. Check out this image of an X-flare on the sun on October 28, 2021. It prompted an aurora alert.

Solar superflares hit Earth multiple times

Scientists found evidence for solar superflares thousands of years ago from evidence in tree rings. Could a solar superflare happen again in the future?

Aurora alert! Pair of CMEs to jolt Earth’s magnetic field

Aurora alert! A pair of coronal mass ejections will reach Earth September 1-2, 2021. Though not dangerous to satellites or the grid, they might cause auroras.

Favorite photos of ‘ring of fire’ solar eclipse

Stunning photos of the June 10, 2021 'ring of fire' solar eclipse photos.

Why is the sun’s atmosphere hotter than its surface?

The sun's atmosphere, or corona - the wispy part we see during solar eclipses - is hundreds of times hotter than the sun's visible surface, or photosphere. Why?

‘Ring of fire’ solar eclipse on June 10

The moon will sweep in front of the sun June 10 to stage 2021's first solar eclipse. A bright ring, the sun's outer rim, will surround the moon at mid-eclipse.

Awaiting the next historic solar storm

Researchers uncovering eyewitness accounts of powerful solar storms of the past say we should expect at least one super-storm from the sun per century.

Check out these new Sun Science stamps!

The US Postal Service announced that they'll be releasing a series of stamps highlighting images of the sun captured by NASA's Solar Dynamics Observatory.

SDO spies its 1st lunar transit of 2021

NASA's Solar Dynamics Observatory has been continuously observing the sun since its launch in 2010. From its vantage point above Earth, it sees the moon pass in front of the sun 2 to 5 times a year.

The sun in 2020

See a whole year of sun images, an image a day for 2020, taken by ESA's Proba-2 satellite.

2026 Donation Campaign

If EarthSky has ever helped you discover something new, prepare for an eclipse, spot a planet, or simply inspired a moment of wonder, today is the perfect day to give back. Your donation helps keep trusted science news, expert night sky guides, and independent science journalism free for everyone.

Please help keep EarthSky going by donating today!

Please help keep

EarthSky going!

If you've already donated, we apologize for the popup and greatly appreciate your support.