APOD: 2023 October 3 Б MyCn 18: The Engraved Hourglass Planetary Nebula
3.10.2023

Do you see the hourglass shape -- or does it see you? If you can picture it, the rings of MyCn 18 trace the outline of an hourglass -- although one with an unusual eye in its center. Either way, the sands of time are running out for the central star of this hourglass-shaped planetary nebula.

APOD: 2026 August 4 Б Curious Cometary Knots in the Helix Nebula
4.08.2026

What causes unusual knots of gas and dust in planetary nebulas? Seen also in the Ring Nebula, the Dumbbell Nebula and NGC 2392, the knots' existence was not initially predicted, and their origins are still not well understood.

An Orion Deep Field
15.01.2004

Adrift 1,500 light-years away in one of the night sky's most recognizable constellations, the glowing Orion Nebula and the dark Horsehead Nebula are contrasting cosmic vistas. They both appear in this stunning composite digital image assembled from over 20 hours of data that includes exposures filtered to record emission from hydrogen atoms.

NGC 4631: The Whale Galaxy
23.01.2004

NGC 4631 is a big beautiful spiral galaxy seen edge-on only 25 million light-years away towards the small northern constellation Canes Venatici. This galaxy's slightly distorted wedge shape suggests to some a cosmic herring and to others the popular moniker of The Whale Galaxy.

Crab Nebula Mosaic from HST
2.12.2005

The Crab Nebula is cataloged as M1, the first object on Charles Messier's famous list of things which are not comets. In fact, the cosmic Crab is now known to be a supernova remnant, an expanding cloud of debris from the death explosion of a massive star.

Geminid Meteor over Monument Valley
12.12.2009

The Geminids are expected to put on a good show this year. Created as planet Earth sweeps through dusty debris from extinct comet Phaethon, the annual Geminid meteor shower is predicted to peak on December 14th, around 0510 UT (12:10am EST).

The Horsehead Nebula
27.12.2017

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.

APOD: 2023 July 18 Б Milky Way above La Palma Observatory
18.07.2023

What's happening in the night sky? To help find out, telescopes all over the globe will be pointing into deep space. Investigations will include trying to understand the early universe, finding and tracking Earth-menacing asteroids, searching for planets that might contain extra-terrestrial life, and monitoring stars to help better understand our Sun.

APOD: 2025 October 26 Б Halloween and the Ghost Head Nebula
26.10.2025

Halloween's origin is ancient and astronomical. Since the fifth century BC, Halloween has been celebrated as a cross-quarter day, a day halfway between an equinox (equal day / equal night) and a solstice (minimum day / maximum night in the northern hemisphere).

The Milky Way Behind an Eclipsed Moon
3.06.2003

What's behind the Moon? Each month, our Moon passes in front of -- and outshines -- many an interesting star field. Exceptions occur during a new Moon and during a total eclipse. In the background...