Diamond Dust Sky Eye
Why is there a huge eye in the sky? Diamond dust. That is an informal term for small ice crystals that form in the air and flitter to the ground. Because these crystals are geometrically shaped, they can together reflect light from the Sun or ...
Fox Fur, Cone, and Christmas Tree
What do the following things have in common: a cone, the fur of a fox, and a Christmas tree? Answer: they all occur in the constellation of the Unicorn (Monoceros). Considered as a star forming region and cataloged as NGC 2264, the complex ...
Christmas Tree Aurora
It was December and the sky lit up like a Christmas tree. Shimmering, the vivid green, blue, and purple auroral colors that formed the tree-like apparition were caused by high atmospheric oxygen and nitrogen reacting to a burst of incoming ...
The Local Fluff
The stars are not alone. In the disk of our Milky Way Galaxy, about 10 percent of visible matter is in the form of gas called the interstellar medium (ISM). The ISM is not uniform and shows patchiness even near our Sun. It can be quite ...
A Year in Sunsets
A year in sunsets, from April 2023 to March 2024, track along the western horizon in these stacked panoramic views. The well-planed sequence is constructed of images recorded near the 21st day of the indicated month from the same location ...
The Long Night Moon
On the night of December 15, the Full Moon was bright. Known to some as the Cold Moon or the Long Night Moon, it was the closest Full Moon to the northern winter solstice and the last Full Moon of 2024. This Full Moon was also at a major lunar ...
Messier 2
After the Crab Nebula, this giant star cluster is the second entry in 18th century astronomer Charles Messier's famous list of things that are not comets. M2 is one of the largest globular star clusters now known to roam the halo of our ...
NGC 660: Polar Ring Galaxy
What kind of strange galaxy is this? This rare structure is known as a polar ring galaxy, and it seems to have two different rings of stars. In this galaxy, NGC 660, one ring of bright stars, gas, and dark dust appears nearly vertical, while ...
Near to the Heart Nebula
What excites the Heart Nebula? First, the large emission nebula on the upper left, catalogued as IC 1805, looks somewhat like a human heart. The nebula glows brightly in red light emitted by its most prominent element, hydrogen, but this ...
A Kilometer High Cliff on Comet...
This kilometer high cliff occurs on the surface of a comet. It was discovered on the dark nucleus of Comet Churyumov - Gerasimenko (CG) by Rosetta, a robotic spacecraft launched by ESA, which orbited the comet from 2014 to 2016. The ragged ...
