The Horsehead Nebula
21.10.2012

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.

Polaris and Comet Lovejoy
1.06.2015

One of these two bright sky objects is moving. On the right is the famous star Polaris. Although only the 45th brightest star in the sky, Polaris is famous for appearing stationary. Once you find it, it will always appear in the same direction -- all night and all day -- for the rest of your life.

Saturn and Mars visit Milky Way Star Clouds
9.05.2016

Planets, stars, nebulas and a galaxy -- this impressive image has them all. Closest to home are the two planets Mars (right) and Saturn (center), visible as the two bright orange spots in the upper half of the featured image.

Eclipse Across America: Path Prediction Video
18.06.2017

Where will you be during the Eclipse across America? On August 21, the shadow of the Moon will cross the continental USA for the first time since 1979. The predicted path -- a certainty given modern astronomical knowledge -- is shown in the featured NASA video.

Colorful Airglow Bands Surround Milky Way
12.03.2022

Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere.

APOD: 2023 April 4 Б Olympus Mons: Largest Volcano in the Solar System
3.04.2023

The largest volcano in our Solar System is on Mars. Although three times higher than Earth's Mount Everest, Olympus Mons will not be difficult for humans to climb because of the volcano's shallow slopes and Mars' low gravity.

APOD: 2023 June 14 Б The Shark Nebula
13.06.2023

There is no sea on Earth large enough to contain the Shark nebula. This predator apparition poses us no danger as it is composed only of interstellar gas and dust. Dark dust like that featured here is somewhat like cigarette smoke and created in the cool atmospheres of giant stars.

APOD: 2024 September 24 Б NGC 6727: The Rampaging Baboon Nebula
23.09.2024

This dusty region is forming stars. Part of a sprawling molecular cloud complex that resembles, to some, a rampaging baboon, the region is a relatively close by 500 light-years away toward the constellation Corona Australis. That's about one third the distance of the more famous stellar nursery known as the Orion Nebula.

Rigel and the Witch Head Nebula
30.10.2024

By starlight, this eerie visage shines in the dark with a crooked profile evoking its popular name, the Witch Head Nebula. In fact, this entrancing telescopic portrait gives the impression that a witch has fixed her gaze on Orion's bright supergiant star Rigel.

APOD: 2025 September 24 Б GW250114: Rotating Black Holes Collide
23.09.2025

It was the strongest gravitational wave signal yet measured -- what did it show? GW250114 was detected by both arms of the Laser Interferometer Gravitational-wave Observatory (LIGO) in Washington and Louisiana USA earlier this year.