Astronomy Picture Of the Day (APOD)Cirrus over Paris
What's that over Paris? Cirrus. Typically, cirrus clouds appear white or gray when reflecting sunlight, can appear dark at sunset (or sunrise) against a better lit sky. Cirrus are among the highest types of clouds and are usually thin enough to see stars through.
NGC 6814: Grand Design Spiral Galaxy from Hubble
In the center of this serene stellar swirl is likely a harrowing black-hole beast. The surrounding swirl sweeps around billions of stars which are highlighted by the brightest and bluest. The breadth and beauty of the display give the swirl the designation of a grand design spiral galaxy.
Sunrise Solstice over Stonehenge
Today the Sun reaches its northernmost point in planet Earth's sky. Called a solstice, the date traditionally marks a change of seasons -- from spring to summer in Earth's Northern Hemisphere and from fall to winter in Earth's Southern Hemisphere.
Galaxy and Planets Beyond Bristlecone Pines
What's older than these ancient trees? Nobody you know -- but almost everything in the background of this picture. The trees are impressively old -- each part of the Ancient Bristlecone Pine Forest located in eastern California, USA.
Sputnik Planum vs. Krun Macula
Pluto's pitted plains meet rugged highlands in this stunning view. On the left lies a southeastern extent of the bright region still informally known as Sputnik Planum. At right the edge of a dark region, informally Krun Macula, rises some 2.5 kilometers above the icy plains.
Comet PanSTARRS in the Southern Fish
Now approaching our fair planet this Comet PanSTARRS (C/2013 X1) will come closest on June 21-22, a mere 5.3 light-minutes away. By then its appearance low in northern hemisphere predawn skies (high in the south), will be affected by the light of a nearly Full Moon, though.
Northern Lights above Lofoten
The Aurora Borealis or northern lights are familiar visitors to night skies above the village of Reine in the Lofoten Islands, Norway, planet Earth. In this scene, captured from a mountaintop camp site, the auroral curtains do seem to create an eerie tension with the coastal lights though.
GW151226: A Second Confirmed Source of Gravitational Radiation
A new sky is becoming visible. When you look up, you see the sky as it appears in light -- electromagnetic radiation. But just over the past year, humanity has begun to see our once-familiar sky as it appears in a different type of radiation -- gravitational radiation.
The North America and Pelican Nebulas
Here lie familiar shapes in unfamiliar locations. On the left is an emission nebula cataloged as NGC 7000, famous partly because it resembles our fair planet's continent of North America. The emission region to the right of the North America Nebula is IC 5070, also known for its suggestive outlines as the Pelican Nebula.
Unexplained Dimmings in KIC 8462852
Why does star KIC 8462852 keep wavering? Nobody knows. A star somewhat similar to our Sun, KIC 8462852 was one of many distant stars being monitored by NASA's robotic Kepler satellite to see if it had planets.