Green Flashes: Sun, Moon, Venus, Mercury
30.05.2020

Follow a sunset on a clear day against a distant horizon and you might glimpse green just as the Sun disappears from view. The green flash is caused by refraction of light rays traveling to the eye over a long path through the atmosphere.

S is for Sun
21.03.2002

Taken yesterday from the SOHO spacecraft, this false-color image shows the active Sun near the March Equinox, the beginning of Fall in the south and Spring in the northern hemisphere. Recorded in a band...

Hole in the Sun
28.08.2010

This ominous, dark shape sprawling across the face of the Sun is a coronal hole -- a low density region extending above the surface where the solar magnetic field opens freely into interplanetary space. Studied...

Sun vs Super Moon
11.05.2012

The Super Moon wins, by just a little, when its apparent size is compared to the Sun in this ingenious composite picture. To make it, the Full Moon on May 6 was photographed with the same camera and telescope used to image the Sun (with a dense solar filter!) on the following day.

The Sun Unleashed: Monster Filament in Ultraviolet
9.04.2018

One of the most spectacular solar sights is an explosive flare. In 2011 June, the Sun unleashed somewhat impressive, medium-sized solar flare as rotation carried active regions of sunpots toward the solar limb. That...

Blue Sun Bristling
4.11.2009

Our Sun may look like all soft and fluffy, but it's not. Our Sun is an extremely large ball of bubbling hot gas, mostly hydrogen gas. The above picture...

An X Class Flare Region on the Sun
6.11.2007

Why does the Sun flare? Unpredictably, our Sun unleashes tremendous flares expelling hot gas into the Solar System that can affect satellites, astronauts, and power grids on Earth. This close up of an active region on the Sun that produced a powerful X-class flare was captured by the orbiting TRACE satellite.

The Flash Spectrum of the Sun
15.11.2013

In a flash, the visible spectrum of the Sun changed from absorption to emission on November 3rd, during the brief total phase of a solar eclipse. That fleeting moment is captured by telephoto lens and diffraction grating in this well-timed image from clearing skies over Gabon in equatorial Africa.

A Year on the Sun
26.04.2013

Our solar system's miasma of incandescent plasma, the Sun may look a little scary here. The picture is a composite of 25 images recorded in extreme ultraviolet light by the orbiting Solar Dynamics Observatory between April 16, 2012 and April 15, 2013.

APOD: 2025 July 30 Б Coronal Loops on the Sun
30.07.2025

Our Sun frequently erupts in loops. Hot solar plasma jumps off the Sun's surface into prominences, with the most common type of prominence being a simple loop. The loop shape originates from the Sun's magnetic field, which is traced by spiraling electrons and protons.