M6: The Butterfly Cluster
3.09.2014

To some, the outline of the open cluster of stars M6 resembles a butterfly. M6, also known as NGC 6405, spans about 20 light-years and lies about 2,000 light years distant. M6, pictured...

Lyrid of the Lake
28.04.2022

In the early hours of April 24 this bright Lyrid meteor flashed along the central Milky Way. For a moment, it cast a bright reflection across Lake Nian, Yunnan province, China. The annual Lyrid...

The Gegenschein Over Chile
7.05.2008

Is the night sky darkest in the direction opposite the Sun? No. In fact, a rarely discernable faint glow known as the gegenschein (German for "counter glow") can be seen 180 degrees around from the Sun in an extremely dark sky. The gegenschein is sunlight back-scattered off small interplanetary dust particles.

The Local Void in the Nearby Universe
6.08.2019

What does our region of the Universe look like? Since galaxies are so spread out over the sky, and since our Milky Way Galaxy blocks part of the distant sky, it has been hard to tell.

M1: The Crab Nebula
25.07.1995

In the year 1054 a star in the constellation of Taurus exploded in a spectacular supernova so bright it appeared to dominate the sky except for the Sun and Moon for many days. It left behind one of the most brilliant nebulae, listed first in Charles Messier's list of nebulous sky objects.

Conjunction of Four
4.02.2017

On January 31, a waxing crescent Moon, brilliant Venus, and fainter Mars gathered in the fading twilight, hanging above the western horizon just after sunset on planet Earth. In this combined evening skyscape, the lovely celestial triangle is seen through clouds and haze.

The Perseid Meteor Shower
9.08.1996

From a radiant point in the constellation of Perseus, Comet Swift-Tuttle presents -- The Perseid Meteor Shower -- coming to your night sky this weekend! A bookish E. C. Herrick of New Haven, Connecticut correctly suspected in 1837 that this meteor shower was an annual event.

Ikeya Zhang: Comet Over Colorado
4.04.2002

Comet Ikeya-Zhang ("ee-KAY-uh JONG") has become a most photogenic comet. This lovely early evening view of the comet in Rocky Mountain skies looks northwest over ridges and low clouds. The time exposure was recorded on March 31st from an 8,000 foot elevation near Yampa, Colorado, USA.

APOD: 2024 December 9 Б Pleiades: The Seven Sisters Star Cluster
9.12.2024

Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as large and clear as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen with the unaided eye even from the depths of a light-polluted city.

M45: The Pleiades Star Cluster
19.10.2016

Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as dusty as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen without binoculars even from the heart of a light-polluted city.