Perihelion Sun 2023
14.01.2023

Perihelion for 2023, Earth's closest approach to the Sun, was on January 4 at 16:17 UTC. That was less than 24 hours after this sharp image of the Sun's disk was recorded with telescope and H-alpha filter from Sidney, Australia, planet Earth.

APOD: 2023 October 25 Б Gone in 60 Seconds: A Green Flash Sunset
25.10.2023

In 60 seconds, this setting Sun will turn green. Actually, the top of the Sun already appears not only green, but wavey -- along with all of its edges. The Sun itself is unchanged -- both effects are caused by looking along hot and cold layers in Earth's atmosphere.

APOD: 2024 May 26 Б A Solar Filament Erupts
26.05.2024

What's happened to our Sun? Nothing very unusual -- it just threw a filament. Toward the middle of 2012, a long standing solar filament suddenly erupted into space, producing an energetic coronal mass ejection (CME).

An Extremely Long Filament on the Sun
9.02.2015

Yesterday, the Sun exhibited one of the longest filaments ever recorded. It may still be there today. Visible as the dark streak just below the center in the featured image, the enormous filament extended across the face of the Sun a distance even longer than the Sun's radius -- over 700,000 kilometers.

Sun and Moon Halo
3.04.2015

Two pictures captured on April 1 are combined in this creative day and night composite. Separated in time by about 10 hours the images otherwise match, looking along the coast at Östersund Sweden.

Circling the Sun
13.01.2024

Earth's orbit around the Sun is not a circle, it's an ellipse. The point along its elliptical orbit where our fair planet is closest to the Sun is called perihelion. This year...

Circular Sun Halo
14.10.2023

Want to see a ring around the Sun? It's easy to do in daytime skies around the world. Created by randomly oriented ice crystals in thin high cirrus clouds, circular 22 degree halos are visible much more often than rainbows.

All the Colors of the Sun
28.06.2015

It is still not known why the Sun's light is missing some colors. Here are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device.

A Large Tsunami Shock Wave on the Sun
22.05.2022

Tsunamis this large don't happen on Earth. During 2006, a large solar flare from an Earth-sized sunspot produced a tsunami-type shock wave that was spectacular even for the Sun. Pictured here, the tsunami...

APOD: 2023 June 11 Б The Sun and Its Missing Colors
11.06.2023

Here are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device. The spectrum was created at the McMath-Pierce Solar Observatory and shows, first off, that although our white-appearing Sun emits light of nearly every color, it appears brightest in yellow-green light.