Pleiades over Half Dome
19.07.2022

Stars come in bunches. The most famous bunch of stars on the sky is the Pleiades, a bright cluster that can be easily seen with the unaided eye. The Pleiades lies only about 450 light years away, formed about 100 million years ago, and will likely last about another 250 million years.

Cassini Looks Out from Saturn
23.12.2022

This is what Saturn looks like from inside the rings. In 2017, for the first time, NASA directed the Cassini spacecraft to swoop between Saturn and its rings. During the dive, the robotic spacecraft took hundreds of images showing unprecedented detail for structures in Saturn's atmosphere.

APOD: 2024 June 9 Б How to Identify that Light in the Sky
9.06.2024

What is that light in the sky? The answer to one of humanity's more common questions may emerge from a few quick observations. For example -- is it moving or blinking?

APOD: 2025 January 6 Б Colliding Spiral Galaxies from Webb and Hubble
6.01.2025

Billions of years from now, only one of these two galaxies will remain. Until then, spiral galaxies NGC 2207 and IC 2163 will slowly pull each other apart, creating tides of matter, sheets of shocked gas, lanes of dark dust, bursts of star formation, and streams of cast-away stars.

APOD: 2026 March 16 Б NGC 1566: The Spanish Dancer Galaxy
16.03.2026

If not perfect, then this spiral galaxy is at least one of the most photogenic. An island universe containing billions of stars and situated about 40 million light-years away toward the constellation of the Dolphinfish (Dorado), NGC 1566 presents a gorgeous face-on view.

APOD: 2026 August 24 Б Comet 220P in Outburst
24.08.2026

Comet 220P is unexpectedly bright. Normally, periodic Comet 220P/McNaught is so dim that to see it requires a telescope. Two surprising outbursts this year, however, have made it about 20,000 times brighter than usual, so that it is now visible with binoculars and long-duration camera exposures.

M2-9: Wings of a Planetary Nebula
23.12.1997

Are stars better appreciated for their art after they die? Actually, stars usually create their most artistic displays as they die. In the case of low-mass stars like our Sun and M2-9 pictured above, the stars transform themselves from normal stars to white dwarfs by casting off their outer gaseous envelopes.

NGC 1808: A Nearby Starburst Galaxy
1.07.1998

NGC 1808 is a galaxy in turmoil. A barred spiral with marked similarities to our home Milky Way Galaxy, NGC 1808 is distinguished by a peculiar nucleus, an unusually warped disk, and strange flows of hydrogen gas out from the central regions.

The Quintuplet Star Cluster
21.09.1999

Bright clusters of stars form and disperse near the center of our Galaxy. Four million years ago the Quintuplet Cluster, pictured above, formed and is now slowly dispersing. The Quintuplet Cluster is located within 100 light-years of the Galactic center, and is home to the brightest star yet cataloged in our Galaxy: the Pistol Star.

The Horsehead Nebula
21.07.2009

One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. Also known as Barnard 33, the unusual shape was first discovered on a photographic plate in the late 1800s.