Solar System Web Cam
14.07.2001

Ranging throughout the solar system, these pictures all have something in common. They were taken with an 8 inch diameter telescope, a size popular with amateur astronomy buffs, and slightly modified "web cam" of the type widely used to send images out over the internet.

3C58: Pulsar Power
23.12.2004

Light from a star that exploded some ten thousand light-years away first reached our fair planet in the year 1181. Now known as supernova remnant 3C58, the region seen in this false-color image glows in x-rays, powered by a rapidly spinning neutron star or pulsar - the dense remains of the collapsed stellar core.

Chilean Skyscape
29.11.2008

Night skies over Chilean mountain top observatories can be dark and clear, with glorious cosmic vistas. In this recent example, the plane of our Milky Way galaxy stretches parallel to the horizon, the galactic center's star clusters, dark dust clouds, and glowing nebulae hovering in the west.

Venus and the Triply Ultraviolet Sun
20.08.2013

An unusual type of solar eclipse occurred last year. Usually it is the Earth's Moon that eclipses the Sun. Last June, most unusually, the planet Venus took a turn. Like a solar eclipse by the Moon, the phase of Venus became a continually thinner crescent as Venus became increasingly better aligned with the Sun.

Milky Way with Airglow Australis
4.09.2015

After sunset on September 1, an exceptionally intense, reddish airglow flooded this Chilean winter night skyscape. Above a sea of clouds and flanking the celestial Milky Way, the airglow seems to ripple and flow across the northern horizon in atmospheric waves.

Red Nebula, Green Comet, Blue Stars
20.12.2018

This festively colored skyscape was captured in the early morning hours of December 17, following Comet Wirtanen's closest approach to planet Earth. The comet was just visible to the eye. The lovely green...

APOD: 2024 June 12 Б Aurora over Karkonosze Mountains
12.06.2024

It was the first time ever. At least, the first time this photographer had ever seen aurora from his home mountains. And what a spectacular aurora it was. The Karkonosze Mountains in Poland are usually too far south to see any auroras.

APOD: 2025 July 8 Б The Pleiades in Red and Blue
8.07.2025

If you have looked at the sky and seen a group of stars about the size of the full Moon, that's the Pleiades (M45). Perhaps the most famous star cluster in the sky, its brightest stars can be seen even from the light-polluted cities.

Keck: The Largest Optical Telescopes
27.12.1997

In buildings eight stories tall rest mirrors ten meters across that are slowly allowing humanity to map the universe. Alone, each is the world's largest optical telescope: Keck. Together, the twin Keck telescopes have the resolving power of a single telescope 90-meter in diameter, able to discern sources just milliarcseconds apart.

NGC 2266: Old Cluster in the New General Catalog
29.04.1999

The New General Catalog of star clusters and nebulae really isn't so new. In fact, it was published in 1888 - an attempt by J. L. E. Dreyer to consolidate the work of astronomers William, Caroline, and John Herschel along with others into a useful single, complete catalog of astronomical discoveries and measurements.