Astronomy Picture Of the Day (APOD)M27 Not a Comet
While hunting for comets in the skies above 18th century France, astronomer Charles Messier diligently kept a list of the things he encountered that were definitely not comets. This is number 27 on his now famous not-a-comet list.
Firefall by Moonlight
On certain dates in February, an elusive firefall can be spotted at sunset in Yosemite National Park, when the weather cooperates and the direction to the setting Sun is just right. Often photographed from...
What would it be like to orbit Jupiter? The dramatic featured video depicts just this and was made from images taken by NASA's Juno spacecraft currently orbiting the Jovian giant. Juno recently completed its sixth pass near Jupiter during its looping elliptical six-week orbit.
The Case of the Missing Star
What's happened to giant star N6946-BH1? It was there just a few years ago -- Hubble imaged it. Now there's only a faint glow. What's curiouser, no bright supernova occurred -- although the star did brightened significantly for a few months.
Highlights of the Summer Sky
What's up in the sky this summer? The featured graphic gives a few highlights for Earth's northern hemisphere. Viewed as a clock face centered at the bottom, early summer sky events fan out toward the left, while late summer events are projected toward the right.
Orion: Belt, Flame, and Horsehead
What surrounds the famous belt stars of Orion? A deep exposure shows everything from dark nebula to star clusters, all embedded in an extended patch of gaseous wisps in the greater Orion Molecular Cloud Complex.
On May 19, the Juno spacecraft once again swung by Jupiter in its looping 53 day orbit around the Solar System's ruling gas gaint. Beginning at the top, this vertical 14 frame sequence of enhanced-color JunoCam images follows the spacecraft's rapidly changing perspective during its two hour passage.
Black Holes of Known Mass
Add GW170104 to the chart of black holes with known mass. The extremely energetic merger of two smaller black holes corresponds to the Laser Interferometer Gravitational-wave Observatory's (LIGO) third detection of gravitational waves.
Shadowrise and Sunset
The road tracking through this stunning 360 degree view crosses a remote mountain area of Jämtland, Sweden, planet Earth. A 3x8 mosaic of still images, the panorama was taken on May 3rd from a small drone 200 meters above the ground.
Approaching the Bubble Nebula
What would it look like to approach the Bubble Nebula? Blown by the wind and radiation from a massive star, this bubble now spans seven light-years in diameter. The hot star inside is thousands of times more luminous than our Sun, and is now offset from the nebula's center.