Saturns Iapetus: Painted Moon
3.06.2018

What has happened to Saturn's moon Iapetus? Vast sections of this strange world are dark as coal, while others are as bright as ice. The composition of the dark material is unknown, but infrared spectra indicate that it possibly contains some dark form of carbon.

Mira Over Germany
21.02.2007

What's that new star in the sky? The star might appear new, but it's actually just the variable star Mira near its brightest. Rolling your cursor over the above vertically compressed image...

APOD: 2023 October 24 Б Arp 87: Merging Galaxies from Hubble
24.10.2023

This dance is to the death. As these two large galaxies duel, a cosmic bridge of stars, gas, and dust currently stretches over 75,000 light-years and joins them. The bridge itself is strong evidence that these two immense star systems have passed close to each other and experienced violent tides induced by mutual gravity.

A Young Supernova in the Nearby Pinwheel Galaxy
26.08.2011

A nearby star has exploded and telescopes all over the world are turning to monitor it. The supernova, dubbed PTF 11kly, was discovered by computer only two days ago as part of the Palomar Transit Factory (PTF) sky survey utilizing the wide angle 1.2-meter Samuel Oschwin Telescope in California.

An Annular Solar Eclipse over New Mexico
25.12.2019

What is this person doing? In 2012 an annular eclipse of the Sun was visible over a narrow path that crossed the northern Pacific Ocean and several western US states. In an annular solar...

NGC 6357: The Lobster Nebula
1.11.2022

Why is the Lobster Nebula forming some of the most massive stars known? No one is yet sure. Cataloged as NGC 6357, the Lobster Nebula houses the open star cluster Pismis 24 near its center -- a home to unusually bright and massive stars.

Aurorae and Lightning on Jupiter
24.03.2021

Why does so much of Jupiter's lightning occur near its poles? Similar to Earth, Jupiter experiences both aurorae and lightning. Different from Earth, though, Jupiter's lightning usually occurs near its poles -- while much of Earth's lightning occurs near its equator.

Curiosity Rover at Rocknest on Mars
27.12.2012

What's in this smooth soil on Mars? In late October, NASA's robotic Curiosity rover stopped near a place dubbed Rocknest as it continues to explore Gale Crater on Mars. Rocknest is the group of stones seen near the top left of the above image -- just to the left of Curiosity's mast.

Giant Cluster Bends, Breaks Galaxy Images
24.04.1996

What are those strange blue objects? Many are images of a single, unusual, beaded, blue, ring-like galaxy which just happens to line-up behind a giant cluster of galaxies. Cluster galaxies here appear yellow and -- together with the cluster's dark matter -- act as a gravitational lens.

Cassini Spacecraft Crosses Saturns Ring Plane
29.12.2019

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.