A Horseshoe Einstein Ring from Hubble
21.12.2011

What's large and blue and can wrap itself around an entire galaxy? A gravitational lens mirage. Pictured above, the gravity of a luminous red galaxy (LRG) has gravitationally distorted the light from a much more distant blue galaxy.

M57: The Ring Nebula from Hubble
17.08.2021

Except for the rings of Saturn, the Ring Nebula (M57) is probably the most famous celestial circle. Its classic appearance is understood to be due to our own perspective, though. The recent mapping...

NGC 922: Collisional Ring Galaxy
17.12.2012

Why does this galaxy have so many big black holes? No one is sure. What is sure is that NGC 922 is a ring galaxy created by the collision of a large and small galaxy about 300 million years ago.

Particle Sizes in Saturns Rings
25.05.2005

What size particles compose Saturn's rings? To help find out, the robot Cassini spacecraft now orbiting Saturn broadcast radio waves of three different wavelengths right through the rings to Earth earlier this month.

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.

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.

Saturn: Bright Tethys and Ancient Rings
16.09.2012

How old are Saturn's rings? No one is quite sure. One possibility is that the rings formed relatively recently in our Solar System's history, perhaps only about 100 million years ago when a moon-sized object broke up near Saturn.

Saturn: Lord of the Rings
17.01.2004

Born in 1564, Galileo used a telescope to explore the Solar System. In 1610, he became the first to be amazed by Saturn's rings, After nearly 400 years, Saturn's magnificent rings still offer one of the most stunning astronomical sights.

APOD: 2023 September 17 Б Moon Mountains Magnified during Ring of Fire Eclipse
17.09.2023

What are those dark streaks in this composite image of a solar eclipse? They are reversed shadows of mountains at the edge of the Moon. The center image, captured from Xiamen, China, has the Moon's center directly in front of the Sun's center.

Cassini Spacecraft Crosses Saturn's Ring Plane
15.02.2010

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.