Mercury Crosses a Quiet Sun
2.12.2019

What's that black dot crossing the Sun? The planet Mercury. Mercury usually passes over or under the Sun, as seen from Earth, but last month the Solar System's innermost planet appeared to go just about straight across the middle.

Space Station Silhouette on the Moon
6.12.2021

What's that unusual spot on the Moon? It's the International Space Station. Using precise timing, the Earth-orbiting space platform was photographed in front of a partially lit gibbous Moon last month.

NGC 3132: The Eight Burst Nebula
13.09.2003

It's the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula. Nicknamed the Eight-Burst Nebula and the Southern Ring Nebula, the glowing gas originated in the outer layers of a star like our Sun.

Saturns Moon Helene from Cassini
10.03.2010

What's happening on the surface of Saturn's moon Helene? The moon was imaged in unprecedented detail last week as the robotic Cassini spacecraft orbiting Saturn swooped to within two Earth diameters of the diminutive moon.

NGC 3132: The Eight Burst Nebula
7.06.2015

It's the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula. Nicknamed the Eight-Burst Nebula and the Southern Ring Nebula, the glowing gas originated in the outer layers of a star like our Sun.

White Rock Fingers on Mars
15.02.2016

What caused this unusual light rock formation on Mars? Intrigued by the possibility that they could be salt deposits left over as an ancient lakebed dried-up, detailed studies of these fingers now indicate a more mundane possibility: volcanic ash. Studying the exact color of the formation indicated the possible volcanic origin.

Venus: Earth's Sister Planet
15.08.1995

This picture in visible light was taken by the Galileo spacecraft. Venus is very similar to Earth in size and mass - and so is sometimes referred to as Earth's sister planet - but Venus has a quite different climate.

APOD: 2023 September 5 Б Blue Supermoon Beyond Syracuse
5.09.2023

The last full moon was doubly unusual. First of all, it was a blue moon. A modern definition of a blue moon is a second full moon to occur during one calendar month. Since there are 13 full moons in 2023, one month has to have two -- and that month was August.

Fractal Interstellar Dust Up-Close
19.11.1996

Our universe is a very dusty place. Dust usually shows its presence by blocking out light emitted from stars or nebula behind it, sometimes creating the illusion of a horse's head or a sombrero hat. But nobody really knows what a typical interstellar dust grain looks like.

NGC 3132: The Eight Burst Nebula
24.06.2001

It's the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula. Nicknamed the Eight-Burst Nebula and the Southern Ring Nebula, the glowing gas originated in the outer layers of a star like our Sun.