The Vela Pulsar s Dynamic Jet
3.07.2003

The Vela pulsar is a neutron star born over 10,000 years ago in a massive supernova explosion. Above, false-color x-ray images from the Chandra Observatory reveal details of this remnant pulsar's x-ray bright nebula along with emission from a spectacular jet of high-energy particles.

A Note on the Perseus Cluster
12.09.2003

A truly enormous collection of thousands of galaxies, the Perseus Cluster - like other large galaxy clusters - is filled with hot, x-ray emitting gas. The x-ray hot gas (not the individual galaxies) appears in the left panel above, a false color image from the Chandra Observatory.

Hidden Treasures of M78
27.01.2011

M78 isn't really hiding in planet Earth's night sky. About 1,600 light-years away and nestled in the nebula rich constellation Orion, the large, bright, reflection nebula is well-known to telescopic skygazers. But this gorgeous image of M78 was selected as the winner of the Hidden Treasures 2010 astrophotography competition.

Halo of the Cat s Eye
20.10.2018

Not a Falcon 9 rocket launch after sunset, the Cat's Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its haunting symmetries are seen in the very...

APOD: 2026 February 16 Б Unexplained Shocks Around a White Dwarf Star
16.02.2026

How is RXJ0528+2838 creating such shock waves? A recently discovered white dwarf star, the farther left of the two largest white spots, RXJ0528+2838, was found 730 light-years away from Earth. Most stars...

The Energetic Jet from Centaurus A
1.05.2003

The center of well-studied active galaxy Centaurus A is hidden from the view of optical telescopes by a cosmic jumble of stars, gas, and dust. But both radio and x-ray telescopes can trace the remarkable jet of high-energy particles streaming from the galaxy's core.

NGC 7293: The Helix Nebula
10.05.2003

Will our Sun look like this one day? The Helix Nebula is the closest example of a planetary nebula created at the end of the life of a Sun-like star. The outer gasses of the star expelled into space appear from our vantage point as if we are looking down a helix.

The Horsehead Nebula in Orion
26.11.2008

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.

A Sagittarius Starscape
5.09.2014

This rich starscape spans nearly 7 degrees on the sky, toward the Sagittarius spiral arm and the center of our Milky Way galaxy. A telescopic mosaic, it features well-known bright nebulae and star clusters cataloged by 18th century cosmic tourist Charles Messier.

APOD: 2026 April 23 Б Large Scale Structure of the Universe
23.04.2026

This is a map of the universe. The Dark Energy Spectroscopic Instrument (DESI) at Kitt Peak National Observatory, Arizona, has finished its five-year survey. It observed more than 47 million galaxies and quasars and created a 3D map centered on the Earth.