A Full Sky Aurora Over Norway
3.01.2012

Higher than the highest building, higher than the highest mountain, higher than the highest airplane, lies the realm of the aurora. Auroras rarely reach below 60 kilometers, and can range up to 1000 kilometers. Aurora light results from energetic electrons and protons striking molecules in the Earth's atmosphere.

Jyvцskylц in the Sky
25.01.2024

You might not immediately recognize this street map of a neighborhood in Jyvцskylц, Finland, planet Earth. But that's probably because the map was projected into the night sky and captured with an allsky camera on January 16. The temperature recorded on that northern winter night was around minus 20 degrees Celsius.

Orion Nebula in Surrounding Dust
25.03.2014

What surrounds a hotbed of star formation? In the case of the Orion Nebula -- dust. The entire Orion field, located about 1600 light years away, is inundated with intricate and picturesque filaments of dust.

Veins of Heaven
31.07.2014

Transfusing sunlight through a a still dark sky, this exceptional display of noctilucent clouds was captured earlier this month above the island of Gotland, Sweden. From the edge of space, about 80 kilometers above...

A Dust Devil on Mars
2.03.2015

It was late in the northern martian spring when the HiRISE camera onboard the Mars Reconnaissance Orbiter spied this local denizen. Tracking across the flat, dust-covered Amazonis Planitia in 2012, the core of this whirling dust devil is about 140 meters in diameter.

The Aurora Tree
28.02.2021

Yes, but can your tree do this? Pictured is a visual coincidence between the dark branches of a nearby tree and bright glow of a distant aurora. The beauty of the aurora -- combined with...

APOD: 2025 September 2 Б The Horsehead and Flame Nebulas
2.09.2025

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the orange emission nebula at the far right of the featured picture. The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright emission nebula.

The Trifid Nebula from AAO
24.04.2002

Unspeakable beauty and unimaginable bedlam can be found together in the Trifid Nebula. Also known as M20, this photogenic nebula is visible with good binoculars towards the constellation of Sagittarius. The energetic processes of star formation create not only the colors but the chaos. The red-glowing gas results from high-energy starlight striking interstellar hydrogen gas.

The Compton Gamma Ray Observatory
11.08.1995

The Compton Gamma Ray Observatory (CGRO) was the most massive instrument ever launched by a NASA Space Shuttle and continues to revolutionize gamma-ray astronomy. This orbiting observatory sees the sky in gamma-ray photons - light so blue humans can't see it.

Betelgeuse
19.04.1998

Here is the first direct picture of the surface of a star other than our Sun. Taken by the Hubble Space Telescope in 1995, the atmosphere of Betelgeuse reveals some unexpected features, including a large bright hotspot visible below the center.