Detailed View of a Solar Eclipse Corona
12.08.2017

Only in the fleeting darkness of a total solar eclipse is the light of the solar corona easily visible. Normally overwhelmed by the bright solar disk, the expansive corona, the sun's outer atmosphere, is an alluring sight.

Launch of the Solar Orbiter
10.02.2020

How does weather on the Sun affect humanity? To help find out, the European Space Agency (ESA) and NASA have just launched the Solar Orbiter. This Sun-circling robotic spaceship will monitor...

Star Forming Region NGC 6357
19.12.2006

For reasons unknown, NGC 6357 is forming some of the most massive stars ever discovered. Near the more obvious Cat's Paw nebula, NGC 6357 houses the open star cluster Pismis 24, home to these tremendously bright and blue stars.

X Ray Stars of Orion
6.10.2007

The stars of Orion shine brightly in visible light in planet Earth's night sky. The constellation harbors the closest large stellar nursery, the Great Nebula of Orion, a mere 1,500 light-years away.

Solar Flare from a Sharper Sun
21.11.2014

Solar active region AR2192 was the largest recorded sunspot group of the last 24 years. Before rotating off the Earth-facing side of the Sun at the end of October, it produced a whopping six energetic X-class flares.

Comet Churyumov Gerasimenko in Crescent
28.04.2015

What's happening to Comet 67P/ChuryumovGerasimenko? As the 3-km wide comet moves closer to the Sun, heat causes the nucleus to expel gas and dust. The Rosetta spacecraft arrived at the comet's craggily double nucleus last July and now is co-orbiting the Sun with the giant dark iceberg.

The Sun in X rays from NuSTAR
28.12.2014

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.

Planetary Nebula Mz3: The Ant Nebula
25.04.2015

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

The Horsehead Nebula
26.12.2017

One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. Also known as Barnard 33, the unusual shape was first discovered on a photographic plate in the late 1800s.

APOD: 2024 May 26 Б A Solar Filament Erupts
25.05.2024

What's happened to our Sun? Nothing very unusual -- it just threw a filament. Toward the middle of 2012, a long standing solar filament suddenly erupted into space, producing an energetic coronal mass ejection (CME).