Hoags Object: A Strange Ring Galaxy
22.08.2010

Is this one galaxy or two? This question came to light in 1950 when astronomer Art Hoag chanced upon this unusual extragalactic object. On the outside is a ring dominated by bright blue stars, while near the center lies a ball of much redder stars that are likely much older.

Rainbow Airglow over the Azores
22.03.2016

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: 2025 April 27 Б IC 418: The Spirograph Nebula
27.04.2025

What is creating the strange texture of IC 418? Dubbed the Spirograph Nebula for its resemblance to drawings from a cyclical drawing tool, planetary nebula IC 418 shows patterns that are not well understood. Perhaps they are related to chaotic winds from the variable central star, which changes brightness unpredictably in just a few hours.

The Milky Way Over Ontario
29.07.2008

Sometimes, after your eyes adapt to the dark, a spectacular sky appears. Such was the case earlier this month over Ontario, Canada, when part of a spectacular sky also became visible in a reflection off a lake.

Rosetta Spacecraft Passes Asteroid Steins
8.09.2008

What's that diamond in the sky? Cruising though space, sometimes you'll come across an unusual object. Such was the case on Friday for ESA's Rosetta spacecraft on it's way to comet Churyumov-Gerasimenko in 2014.

Perijove 11: Passing Jupiter
8.09.2019

Here comes Jupiter! NASA's robotic spacecraft Juno is continuing on its 53-day, highly-elongated orbits around our Solar System's largest planet. The featured video is from perijove 11 in early 2018, the eleventh time Juno has passed near Jupiter since it arrived in mid-2016.

Hills Ridges and Tracks on Mars
26.01.2020

Sometimes, even rovers on Mars stop to admire the scenery. Just late last November the Curiosity rover on Mars paused to photograph its impressive surroundings. One thing to admire, straight ahead, was Central Butte, an unusual flat hill studied by Curiosity just a few days before this image was taken.

The Surface of Venus from Venera 13
17.03.2021

If you could stand on Venus -- what would you see? Pictured is the view from Venera 13, a robotic Soviet lander which parachuted and air-braked down through the thick Venusian atmosphere in March of 1982.

APOD: 2025 February 16 Б Perijove 11: Passing Jupiter
16.02.2025

Here comes Jupiter. NASA's robotic spacecraft Juno is continuing on its highly elongated orbits around our Solar System's largest planet. The featured video is from perijove 11 in early 2018, the eleventh time Juno passed near Jupiter since it arrived in mid-2016.

APOD: 2025 November 16 Б Crossing Saturns Ring Plane
16.11.2025

If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear.