X Rays Indicate Star Ripped Up by Black Hole
23.02.2004

What could rip a star apart? A black hole. Giant black holes in just the right mass range would pull on the front of a closely passing star much more strongly than on the back.

Mercury And The Sun
18.11.1999

Just days before the peak of the Leonid meteor shower, skywatchers were offered another astronomical treat as planet Mercury crossed the face of the Sun on November 15. Viewed from planet Earth, a transit of Mercury is not all that rare. The last occurred in 1993 and the next will happen in 2003.

Bright Galaxy NGC 2903
6.07.2007

Spiral galaxy NGC 2903 is only some 20 million light-years distant in the constellation Leo. One of the brighter galaxies visible from the northern hemisphere, it is surprisingly missing from Charles Messier's famous catalog of celestial sights. This impressively sharp color image shows off the galaxy's beautiful blue spiral arms.

Comet Holmes Coma Expands
29.10.2007

Go outside tonight and see Comet Holmes. No binoculars or telescopes are needed -- just curiosity and a sky map. Last week, Comet 17P/Holmes underwent an unusual outburst that vaulted it unexpectedly from obscurity into one of the brightest comets in recent years.

Despina, Moon of Neptune
3.09.2009

Despina is a tiny moon of Neptune. A mere 148 kilometers across, diminutive Despina was discovered in 1989, in images from the Voyager 2 spacecraft taken during its encounter with the solar system's most distant gas giant planet.

The Antennae
7.05.2010

Some 60 million light-years away in the southerly constellation Corvus, two large galaxies collided. But the stars in the two galaxies cataloged as NGC 4038 and NGC 4039 don't collide in the course of the ponderous, billion year or so long event.

Meteor before Galaxy
16.08.2016

What's that green streak in front of the Andromeda galaxy? A meteor. While photographing the Andromeda galaxy last Friday, near the peak of the Perseid Meteor Shower, a sand-sized rock from deep space crossed right in front of our Milky Way Galaxy's far-distant companion.

APOD: 2023 December 13 Б Deep Field: The Heart Nebula
12.12.2023

What excites the Heart Nebula? First, the large emission nebula on the left, catalogued as IC 1805, looks somewhat like a human heart. The nebula glows brightly in red light emitted by its most prominent element, hydrogen, but this long-exposure image was also blended with light emitted by silicon (yellow) and oxygen (blue).

APOD: 2025 November 26 Б Globular Cluster M15 Deep Field
25.11.2025

Stars, like bees, swarm around the center of bright globular cluster M15. The central ball of over 100,000 stars is a relic from the early years of our Galaxy, and continues to orbit the Milky Way's center.

NGC 1316: After Galaxies Collide
2.09.2008

Astronomers turn detectives when trying to figure out the cause of startling sights like NGC 1316. Their investigation indicates that NGC 1316 is an enormous elliptical galaxy that started, about 100 million years ago, to devour a smaller spiral galaxy neighbor, NGC 1317, just above it.