Astronomy Picture of the Day

photo X-Ray Superbubbles in Galaxy NGC 3079

X-Ray Superbubbles in Galaxy NGC 3079

What created these huge galactic superbubbles? Two of these unusual bubbles, each spanning thousands of light-years, were recently discovered near the center of spiral galaxy NGC 3079. The superbubbles, shown in purple on the image right, are so ...

See full description

photo Celestial Alignment over Sicilian Shore

Celestial Alignment over Sicilian Shore

This was a sunrise to remember. About a month ago, just before the dawn of the Sun, an impressive alignment of celestial objects was on display to the east. Pictured, brightest and closest to the horizon, is the Moon. The Moon's orange glow is ...

See full description

photo The Orion Bullets

The Orion Bullets

Why are bullets of gas shooting out of the Orion Nebula? Nobody is yet sure. First discovered in 1983, each bullet is actually about the size of our Solar System, and moving at about 400 km/sec from a central source dubbed IRc2. The age of the ...

See full description


photo NGC 6302: The Butterfly Nebula

NGC 6302: The Butterfly Nebula

The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects. Though its wingspan covers over 3 light-years, NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the ...

See full description

photo A Charioteer's Comet

A Charioteer's Comet

Still racing across planet Earth's night skies, Comet Iwamoto (C/2018 Y1) shares this pretty telescopic field of view with stars and nebulae of northern constellation Auriga, the Charioteer. Captured on February 27, Iwamoto's greenish coma and ...

See full description

photo Sharpest Ultima Thule

Sharpest Ultima Thule

On January 1, New Horizons swooped to within 3,500 kilometers of the Kuiper Belt world known as Ultima Thule. That's about 3 times closer than its July 2015 closest approach to Pluto. The spacecraft's unprecedented feat of navigational precision, ...

See full description

photo Magnetic Orion

Magnetic Orion

Can magnetism affect how stars form? Recent analysis of Orion data from the HAWC+ instrument on the airborne SOFIA observatory indicate that, at times, it can. HAWC+ is able to measure the polarization of far-infrared light which can reveal the ...

See full description

photo Simulation TNG50: A Galaxy Cluster Forms

Simulation TNG50: A Galaxy Cluster Forms

How do clusters of galaxies form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out. A recent effort is TNG50 from IllustrisTNG, an upgrade of the famous Illustris Simulation. The first ...

See full description

photo Red Sprite Lightning over Kununurra

Red Sprite Lightning over Kununurra

What are those red filaments in the sky? It is a rarely seen form of lightning confirmed only about 30 years ago: red sprites. Recent research has shown that following a powerful positive cloud-to-ground lightning strike, red sprites may start as ...

See full description

photo The Expanding Echoes of Supernova 1987A

The Expanding Echoes of Supernova 1987A

Can you find supernova 1987A? It isn't hard -- it occurred at the center of the expanding bullseye pattern. Although this stellar detonation was first seen in 1987, light from SN 1987A continued to bounce off clumps of interstellar dust and be ...

See full description