APOD is One Year Old Today
16.06.1996

The first Astronomy Picture of the Day (APOD) appeared one year ago today. Pictured above are Robert Nemiroff (left) and Jerry Bonnell (right), engaged in creating the APOD web pages. APOD started over speculative conversations on the ultimate value of the World Wide Web.

X Rays from the Galactic Core
8.01.2003

Using the orbiting Chandra X-ray Observatory, astronomers have taken this long look at the core of our Milky Way galaxy, some 26,000 light-years away. The spectacular false-color view spans about 130 light-years.

Iridium Flare
2.04.1998

Have you seen an Iridium flare? Satellites in low Earth orbit reflect sunlight and are often visible gliding across early evening and predawn skies. But sun glints from Iridium commercial digital communications satellites are providing the most spectacular sightings.

NGC 1 and NGC 2
19.08.2005

Beautiful nebulae, clusters, and galaxies that grace planet Earth's night sky are often known by their New General Catalog designation or NGC number. That classic listing was compiled by John Louis Emil Dreyer, remarkable director of the Armagh Observatory from 1882 to 1916.

Andromeda Island Universe
22.12.2005

The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy some two million light-years away. But without a telescope, even this immense spiral galaxy - spanning over 200,000 light years - appears as a faint, nebulous cloud in the constellation Andromeda.

Three Nebulae in Narrow Band
2.11.2007

Narrow band filters and a false-color palette give these three nebulae a stunning appearance against the cosmic canvas of the central Milky Way. All three are stellar nurseries about 5,000 light-years or so distant, toward the nebula rich constellation Sagittarius.

Messier Craters in Stereo
8.06.2013

Many bright nebulae and star clusters in planet Earth's sky are associated with the name of astronomer Charles Messier, from his famous 18th century catalog. His name is also given to these two large and remarkable craters on the Moon.

NGC 253: Dusty Island Universe
26.07.2014

Shiny NGC 253 is one of the brightest spiral galaxies visible, and also one of the dustiest. Some call it the Silver Dollar Galaxy for its appearance in small telescopes, or just the Sculptor Galaxy for its location within the boundaries of the southern constellation Sculptor.

Firing Lasers to Tame the Sky
10.02.2021

Why do stars twinkle? Our atmosphere is to blame as pockets of slightly off-temperature air, in constant motion, distort the light paths from distant astronomical objects. Atmospheric turbulence is a problem for astronomers because it blurs the images of the sources they want to study.

APOD: 2025 January 12 Б Mimas: Small Moon with a Big Crater
12.01.2025

Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn's smallest round moons. Analysis indicates that a slightly larger impact would have destroyed Mimas entirely.