Astronomy Picture Of the Day (APOD)Saturns Hexagon and Rings
Why would clouds form a hexagon on Saturn? Nobody is sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System.
Mercury on the Horizon
Have you ever seen the planet Mercury? Because Mercury orbits so close to the Sun, it never wanders far from the Sun in Earth's sky. If trailing the Sun, Mercury will be visible low on the horizon for only a short while after sunset.
The Great Russian Meteor of 2013
What in heaven's blazes is that? Thousands of people living near the Ural Mountains in Russia saw last Friday morning one of the more spectacular meteors of modern times streak across the sky. Forceful sound waves arrived at the ground minutes later, knocking people over and breaking windows for hundreds of kilometers.
Asteroid 2012 DA14 Passes the Earth
There it goes. That small spot moving in front of background stars in the above video is a potentially dangerous asteroid passing above the Earth's atmosphere. This past Friday, the 50-meter wide asteroid...
Sweeping Through Southern Skies
For now, Comet Lemmon (C/2012 F6a), and Comet PanSTARRS (C/2011 L4) are sweeping through southern skies. Lemmon's lime green coma and thin tail are near the left edge of this telephoto scene, a single frame from a timelapse video (vimeo here) recorded on February 12, tracking its motion against the background stars.
Shadows Across Jupiter
Two dark shadows loom across the banded and mottled cloud tops of Jupiter in this sharp telescopic view. In fact, captured on January 3rd, about a month after the ruling gas giant appeared at opposition in planet Earth's sky, the scene includes the shadow casters.
Solar System Portrait
On another Valentine's Day (February 14, 1990), cruising four billion miles from the Sun, the Voyager 1 spacecraft looked back to make this first ever family portrait of our Solar System. The complete portrait is a 60 frame mosaic made from a vantage point 32 degrees above the ecliptic plane.
Infrared Orion from WISE
The Great Nebula in Orion is a intriguing place. Visible to the unaided eye, it appears as a small fuzzy patch in the constellation of Orion. But this image, an illusory-color composite of four...
Reflected Aurora Over Alaska
Some auroras can only be seen with a camera. They are called subvisual and are too faint to be seen with the unaided eye. In the above image, the green aurora were easily visible to the eye, but the red aurora only became apparent after a 20-second camera exposure.
N11: Star Clouds of the LMC
Massive stars, abrasive winds, mountains of dust, and energetic light sculpt one of the largest and most picturesque regions of star formation in the Local Group of Galaxies. Known as N11, the region...