A Sun Halo Beyond Stockholm
10.01.2011

What's happened to the Sun? Sometimes it looks like the Sun is being viewed through a large lens. In the above case, however, there are actually millions of lenses: ice crystals. As water freezes in the upper atmosphere, small, flat, six-sided, ice crystals might be formed.

NanoSail D
28.01.2011

Featured in this artist's illustration, NASA's NanoSail-D finally unfurled a very thin, 10 square meter reflective sail on January 20th, becoming the first solar sail spacecraft in low Earth orbit. Often considered...

A Dangerous Sunrise on Gliese 876d
29.04.2012

On planet Gliese 876d, sunrises might be dangerous. Although nobody really knows what conditions are like on this close-in planet orbiting variable red dwarf star Gliese 876, the above artistic illustration gives one impression.

A Flag Shaped Aurora over Sweden
30.03.2015

It appeared, momentarily, like a 50-km tall banded flag. In mid-March, an energetic Coronal Mass Ejection directed toward a clear magnetic channel to Earth led to one of the more intense geomagnetic storms of recent years. A visual result was wide spread auroras being seen over many countries near Earth's magnetic poles.

A Mercury Transit Music Video from SDO
21.10.2019

What's that small black dot moving across the Sun? Mercury. Possibly the clearest view of Mercury crossing in front of the Sun in 2016 May was from Earth orbit. The Solar Dynamics Observatory obtained an uninterrupted vista recording it not only in optical light but also in bands of ultraviolet light.

Sun Pillar with Upper Tangent Arc
17.02.2021

This was not a typical sun pillar. Just after sunrise two weeks ago in Providence, Rhode Island, USA, a photographer, looking out his window, was suddenly awestruck. The astonishment was caused by a sun pillar that fanned out at the top.

Colorful Airglow Bands Surround Milky Way
13.03.2022

Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere.

APOD: 2023 June 14 Б The Shark Nebula
14.06.2023

There is no sea on Earth large enough to contain the Shark nebula. This predator apparition poses us no danger as it is composed only of interstellar gas and dust. Dark dust like that featured here is somewhat like cigarette smoke and created in the cool atmospheres of giant stars.

Rigel and the Witch Head Nebula
31.10.2024

By starlight, this eerie visage shines in the dark with a crooked profile evoking its popular name, the Witch Head Nebula. In fact, this entrancing telescopic portrait gives the impression that a witch has fixed her gaze on Orion's bright supergiant star Rigel.

Blue Marble 2000
20.04.2000

This newly released digital portrait of our planet is reminiscent of the Apollo-era pictures of the "big blue marble" Earth from space. To create it, researchers at Goddard Space Flight Center's Laboratory...