Gliese 581 and the Habitable Zone
26.04.2007

The faint, unremarkable star centered in this skyview is Gliese 581, a mere 20 light-years away toward the constellation Libra. But astronomers are now reporting the discovery of a remarkable system of three planets orbiting Gliese 581, including the most earth-like planet found beyond our solar system.

A Triple Sunrise Over Gdansk Bay
4.08.2009

How can the same Sun rise three times? Last month on Friday, 2009 July 10, a spectacular triple sunrise was photographed at about 4:30 am over Gdansk Bay in Gdansk, Poland. Clearly, our Sun rises only once. Some optical effect is creating at least two mirages of the Sun -- but which effect?

APOD: 2026 June 22 Б M27: The Dumbbell Nebula
22.06.2026

Is this what will become of our Sun? Quite possibly. The first hint of our Sun's future was discovered inadvertently in 1764. At that time, Charles Messier was compiling a list of diffuse objects not to be confused with comets.

The Complex Ion Tail of Comet Lovejoy
20.01.2015

What causes the structure in Comet Lovejoy's tail? Comet C/2014 Q2 (Lovejoy), which is currently at naked-eye brightness and near its brightest, has been showing an exquisitely detailed ion tail. As the name...

Asteroid 3753: Earth's Curious Companion
18.06.1997

Earth is not alone. It orbits the Sun with a small companion: Asteroid 3753. First discovered in 1986 and designated 1986 OT, this five kilometer rock was recently found to orbit the Sun while executing a strange dance with the Earth. A portion of the asteroid's complex orbit is shown above.

Trees, Stars, Aurora
9.02.2012

Have you ever seen an aurora? Auroras are occurring again with increasing frequency. With the Sun being unusually dormant over the past four years, the amount of Sun-induced auroras has been unusually low. More recently, however, our Sun has become increasingly active and exhibiting a greater abundance of sunspots, flares, and coronal mass ejections.

A Mars Glint
8.06.1998

If aligned just right, even a planet can produce a glint. The above combined pictures of Mars make the red planet appear unusually elongated - Mars is really almost spherical. However, these pictures were taken when the Sun was nearly directly behind the Mars Global Surveyor (MGS) spacecraft.

A Yukon Aurora
8.10.2001

Last week was another good week for auroras. The story began about two weeks ago when two large Coronal Mass Ejections exploded off the Sun. Waves of elementary particles and ions swept out past the Earth on September 28 and 29, causing many auroras.

Annular Eclipse After Sunrise
2.03.2017

From northern Patagonia, morning skies were clear and blue on Sunday, February 26. This sweeping composite scene, overlooking Hermoso Valle, Facundo, Chubut, Argentina, follows the Sun after sunrise, capturing an annular solar eclipse. Created...

Bailys Beads near Solar Eclipse Totality
11.11.2012

Just before the Sun blacks out, something strange occurs. As the Moon moves to completely cover the Sun in a total solar eclipse -- like the one set to occur over parts of Australia on Tuesday -- beads of bright sunlight stream around the edge of the Moon.