A Lunar Corona with Jupiter and Saturn
18.01.2021

Why does a cloudy moon sometimes appear colorful? The effect, called a lunar corona, is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud. Since light of different colors has different wavelengths, each color diffracts differently.

Saturns Moon Helene in Color
2.05.2012

Although its colors may be subtle, Saturn's moon Helene is an enigma in any light. The moon was imaged in unprecedented detail last June as the robotic Cassini spacecraft orbiting Saturn swooped to within a single Earth diameter of the diminutive moon.

Earth and Moon through Saturns Rings
26.05.2020

What are those dots between Saturn's rings? Our Earth and Moon. Just over three years ago, because the Sun was temporarily blocked by the body of Saturn, the robotic Cassini spacecraft was able to look toward the inner Solar System.

Northern Summer on Titan
19.06.2020

Today's solstice brings summer to planet Earth's northern hemisphere. But the northern summer solstice arrived for ringed planet Saturn over three years ago on May 24, 2017. Orbiting the gas giant, Saturn's moon Titan experiences the Saturnian seasons.

Meteors Between Stars and Clouds
10.12.2002

Streaking high above diffuse clouds -- but well in front of distant stars -- are sand-sized bits of an ancient comet: meteors. These bits flaked off Comet Tempel-Tuttle during its pass through the inner Solar System about 150 years ago. Far in the background are stars toward the constellation of Ursa Major.

A Fire Rainbow over West Virginia
29.08.2021

What's happening to this cloud? Ice crystals in a distant cirrus cloud are acting like little floating prisms. Known informally as a fire rainbow for its flame-like appearance, a circumhorizon arc appears parallel to the horizon.

APOD: 2020 August 13 Б Jupiter and Saturn Rising Beyond Alien Throne Rock
12.08.2020

Whatбplanets are those behind that unusualбrock spire? Saturn (lower left) and Jupiter.б This month, after sunset, the bright planetary duo are quite prominent toward the southeast.б Now your view of our Solar...

Great Conjunction over Sicilian Lighthouse
7.12.2020

DonБt miss the coming great conjunction. In just under two weeks, the two largest planets in our Solar System will angularly pass so close together in Earth's sky that the Moon would easily be able to cover them both simultaneously. This pending planetary passage -- on December 21 -- will be the closest since 1623.

Saturn and Jupiter in Summer 2020
11.12.2020

During this northern summer Saturn and Jupiter were both near opposition, opposite the Sun in planet Earth's sky. Their paired retrograde motion, seen about every 20 years, is followed from 19 June through 28 August in this panoramic composite as they wander together between the stars in western Capricornus and eastern Sagittarius.

Jupiter and Saturn Great Conjunction: The Movie
29.12.2020

Yes, but have you seen a movie of Jupiter and Saturn's Great Conjunction? The featured time-lapse video was composed from a series of images taken from Thailand and shows the two giant planets as they angularly passed about a tenth of a degree from each other.