M100 and the Expanding Universe
9.01.1996

The distance to the swirling grand design spiral M100 is causing quite a stir among astronomers. Many believe that the Hubble Space Telescope's recent distance measurement to this galaxy accurately calibrates the expansion rate of the universe. Others believe this distance measurement is misleading.

The Galactic Center in Infrared
7.11.2004

The center of our Galaxy is a busy place. In visible light, much of the Galactic Center is obscured by opaque dust. In infrared light, however, dust glows more and obscures less, allowing nearly one million stars to be recorded in the above photograph.

Spherical Planetary Nebula Abell 39
8.10.2012

Ghostly in appearance, Abell 39 is a remarkably simple, spherical nebula about five light-years across. Well within our own Milky Way galaxy, the cosmic sphere is roughly 7,000 light-years distant toward the constellation Hercules.

Millions of Stars in Omega Centauri
29.05.2014

Globular star cluster Omega Centauri, also known as NGC 5139, is some 15,000 light-years away. The cluster is packed with about 10 million stars much older than the Sun within a volume about...

Arches Across an Arctic Sky
13.01.2021

What are these two giant arches across the sky? Perhaps the more familiar one, on the left, is the central band of our Milky Way Galaxy. This grand disk of stars and nebulas here appears to encircle much of the southern sky.

An Artful Sky over Lofoten Islands
13.12.2022

Can the night sky be both art and science? If so, perhaps the featured image is an example. The digital panorama was composed of 10 landscape and 10 sky images all taken on the same night, from the same location, and with the same camera.

Lynds Dark Nebula 1251
22.06.2024

Stars are forming in Lynds Dark Nebula (LDN) 1251. About 1,000 light-years away and drifting above the plane of our Milky Way galaxy, LDN 1251 is also less appetizingly known as "The Rotten Fish Nebula." The dusty molecular cloud is part of a complex of dark nebulae mapped toward the Cepheus flare region.

A Black Hole in M87?
5.04.1997

The center of nearby giant galaxy M87 is a dense and violent place. In this 1994 photograph by the Hubble Space Telescope, a disk of hot gas was found to be orbiting at the center of this massive elliptical galaxy. The disk is evident at the lower left of the picture.

APOD: 2015 July 7 The Milky Way from a Malibu Sea Cave
7.07.2015

Whats happening outside this cave? Nothing unexpected its just the central band of our Milky Way Galaxy passing by. As the Earth turns, the band of our Galaxy appears to rotate and shift along the horizon.

M82 s Middle Mass Black Hole
14.09.2000

Black holes are probably the most bizarre creatures in the modern astronomical zoo. And after years of pondering black holes as either stellar mass objects seen in binary star systems or enormous supermassive black holes at the centers of galaxies, astronomers now have strong evidence