Geminid Meteors over Xinglong...

2015-12-23 Steed Yu

Where do Geminid meteors come from? In terms of location on the sky, as the featured image composite beautifully demonstrates, the sand-sized bits of rock that create the streaks of the Geminid Meteor Shower appear to flow out from the ...

Solstice Illuminated: A Year of Sky

2015-12-22 Ken Murphy

Can you find which day is the winter solstice? Each panel shows one day. With 360 movie panels, the sky over (almost) an entire year is shown in time lapse format as recorded by a video camera on the roof of the Exploratorium museum in San ...

SN Refsdal: The First Predicted...

2015-12-21

It's back. Never before has an observed supernova been predicted. The unique astronomical event occurred in the field of galaxy cluster MACS J1149.5+2223. Most bright spots in the featured image are galaxies in this cluster. The actual ...

A Dark Earth with a Red Sprite

2015-12-20

There is something very unusual in this picture of the Earth -- can you find it? A fleeting phenomenon once thought to be only a legend has been newly caught if you know just where to look. The featured image was taken from the orbiting ...

Star Streams and the Whale Galaxy

2015-12-19 R Jay Gabany

NGC 4631 is a spiral galaxy found only 25 million light-years away, toward the well-trained northern constellation Canes Venatici. Seen egde-on, the galaxy is similar in size to the Milky Way. Its distorted wedge shape suggests to some a cosmic ...

Herbig-Haro 24

2015-12-18

This might look like a double-bladed lightsaber, but these two cosmic jets actually beam outward from a newborn star in a galaxy near you. Constructed from Hubble Space Telescope image data, the stunning scene spans about half a light-year across ...

Geminids of the South

2015-12-17 Yuri Beletsky

rth's annual Geminid meteor shower did not disappoint, peaking before dawn on December 14 as our fair planet plowed through dust from active asteroid 3200 Phaethon. Captured in this southern hemisphere nightscape the meteors stream away from the ...

The Horsehead Nebula

2015-12-16 José Jiménez Priego

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula in the center of the above photograph. The horse-head feature is dark because it is really an opaque dust cloud ...

Colorful Arcs over Buenos Aires

2015-12-15 Sergio Montúfar

What are those colorful arcs in the sky? Like rainbows that are caused by rain, arcs of sunlight broken up into component colors can also result when ice crystals floating in Earth's atmosphere act together as a gigantic prism. The top color arc ...

Pluto: From Mountains to Plains

2015-12-14

What do the sharpest views ever of Pluto show? As the robotic New Horizons spacecraft moves into the outer Solar System, it is now sending back some of the highest resolution images from its historic encounter with Pluto in July. Featured here is ...