Shell Game in the LMC
18.05.2006

An alluring sight in dark southern skies, the Large Magellanic Cloud (LMC) is seen here through a narrow filter that transmits only the red light of hydrogen atoms. Ionized by energetic starlight, a hydrogen atom emits the characteristic red H-alpha light as its single electron is recaptured and transitions to lower energy states.

Mysterious Green Patches on the Sky
30.09.2013

What is it? Some surely natural phenomenon has appeared in a video that, so far, has defied clear identification. The above time-lapse video was made to record Perseid meteors above Hopewell Rocks in New Brunswick, Canada late this summer.

APOD: 2024 October 16 Б Colorful Aurora over New Zealand
16.10.2024

Sometimes the night sky is full of surprises. Take the sky over Lindis Pass, South Island, New Zealand one-night last week. Instead of a typically calm night sky filled with constant stars, a busy and dynamic night sky appeared.

Compton Returns
7.03.2001

On 2000 June 4, the 17-ton Compton Gamma-Ray Observatory returned to Earth after 9 years in orbit -- ending its remarkable voyage of discovery. The massive, bus-sized spacecraft carried an unprecedented array of gamma-ray detectors which explored the bizarre, high-energy universe of solar flares, black holes, pulsars, supernovae, active galaxies, and gamma-ray bursts.

Stars and Dust Pillars in NGC 7822 from WISE
30.11.2014

Hot, young stars and cosmic pillars of gas and dust seem to crowd into NGC 7822. At the edge of a giant molecular cloud toward the northern constellation Cepheus, this glowing star forming region lies about 3,000 light-years away.

The Sun in X rays from NuSTAR
23.11.2021

Why are the regions above sunspots so hot? Sunspots themselves are a bit cooler than the surrounding solar surface because the magnetic fields that create them reduce convective heating. It is therefore unusual that regions overhead -- even much higher up in the Sun's corona -- can be hundreds of times hotter.

Centaurus A: The Galaxy Deep Inside
4.12.1998

Deep inside Centaurus A, the closest active galaxy to Earth, lies ... another galaxy! Cen A is a giant elliptical galaxy a mere 10 million light-years distant with a central jumble of stars, dust, and gas that probably hides a massive black hole.

NGC 7822: Stars and Dust Pillars in Infrared
19.11.2017

Young stars themselves are clearing out their nursery in NGC 7822. Within the nebula, bright edges and complex dust sculptures dominate this detailed skyscape taken in infrared light by NASA's Wide Field Infrared Survey Explorer (WISE) satellite.

Full Moon Silhouettes
10.10.2021

Have you ever watched the Moon rise? The slow rise of a nearly full moon over a clear horizon can be an impressive sight. One impressive moonrise was imaged in early 2013 over Mount Victoria Lookout in Wellington, New Zealand.

Halloween and the Ghost Head Nebula
24.10.2021

Halloween's origin is ancient and astronomical. Since the fifth century BC, Halloween has been celebrated as a cross-quarter day, a day halfway between an equinox (equal day / equal night) and a solstice (minimum day / maximum night in the northern hemisphere).