The Analemma and the Temple of Olympian Zeus
22.12.2006

An analemma is that figure-8 curve you get when you mark the position of the Sun at the same time each day throughout planet Earth's year. Above, 47 separate exposures (plus one foreground...

A Starry Night of Iceland
17.05.2011

On some nights, the sky is the best show in town. On this night, the sky was not only the best show in town, but a composite image of the sky won an international competition for landscape astrophotography. The above winning image was taken two months ago over JЖkulsАrlСn, the largest glacial lake in Iceland.

A Colorful Lunar Corona
14.06.2015

What are those colorful rings around the Moon? A corona. Rings like this will sometimes appear when the Moon is seen through thin clouds. The effect is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud.

APOD: 2023 August 23 Б The Meteor and the Galaxy
22.08.2023

It came from outer space. It -- in this case a sand-sized bit of a comet nucleus -- was likely ejected many years ago from Sun-orbiting Comet Swift-Tuttle, but then continued to orbit the Sun alone.

The Solar Wind Emerges
7.02.1999

Winds of fast particles blow out from the Sun, but why? Astronomers came a step closer to answering this question recently by making detailed observations of the high-speed wind source with the space-borne Solar and Heliospheric Observatory (SOHO).

Sunspot Seething
22.02.2000

Our Sun's surface is continually changing. This time-lapse movie shows in five seconds what happens in 20 minutes on the Sun's surface near a sunspot. Visible is boiling granulation outside the sunspot...

IC 1805: The Heart Nebula in HDR
25.10.2011

What powers the Heart Nebula? The large emission nebula dubbed IC 1805 looks, in whole, like a human heart. The nebula glows brightly in red light emitted by its most prominent element: hydrogen. The red glow and the larger shape are all created by a small group of stars near the nebula's center.

The Pale Blue Dot
13.02.2020

On Valentine's Day in 1990, cruising four billion miles from the Sun, the Voyager 1 spacecraft looked back one last time to make the first ever Solar System family portrait. The portrait consists...

Ghirigori Star Scribbles
11.08.2023

It's fun to scribble on the canvas of the sky. You can use a creative photographic technique to cause the light of point-like stars to dance across a digital image by tapping lightly on the telescope while making an exposure.

APOD: 2024 January 14 Б Dragon Aurora over Iceland
13.01.2024

Have you ever seen a dragon in the sky? Although real flying dragons don't exist, a huge dragon-shaped aurora developed in the sky over Iceland in 2019. The aurora was caused...