M51: Cosmic Whirlpool
28.04.2005

Follow the handle of the Big Dipper away from the dipper's bowl, until you get to the handle's last bright star. Then, just slide your telescope a little south and west and you might find this stunning pair of interacting galaxies, the 51st entry in Charles Messier's famous catalog.

At the Limit of Diffraction
7.05.2015

Did you ever want to just look through the eyepiece of a large telescope in space? If you could, you would see a sharp view that was diffraction limited. Unaffected by atmospheric blurring that...

Abell 2744: Pandoras Cluster of Galaxies
29.06.2011

Why is this cluster of galaxies so jumbled? Far from a smooth distribution, Abell 2744 not only has knots of galaxies, but the X-ray emitting hot gas (colored red) in the cluster appears distributed differently than the dark matter.

First Horizon Scale Image of a Black Hole
11.04.2019

What does a black hole look like? To find out, radio telescopes from around the Earth coordinated observations of black holes with the largest known event horizons on the sky. Alone, black holes are just black, but these monster attractors are known to be surrounded by glowing gas.

NGC 6369: A Donut Shaped Nebula
18.05.1998

Why isn't the star in the center of the nebula? NGC 6369 appears to be a fairly ordinary planetary nebula. It can be seen with a good telescope in the constellation of Ophiuchus. The gas expelled by the central star is bunched in the shape of a donut or cylinder.

NGC 2997 from VLT
10.03.1999

Add another 8-meter telescope to the list of modern optical telescope giants. Kueyen achieved a first-light photograph of a bright star on March 1, ahead of schedule. The above picture of spiral galaxy...

Tentacles of the Tarantula Nebula
28.12.2004

The Tarantula Nebula is a giant emission nebula within our neighboring galaxy the Large Magellanic Cloud. Inside this cosmic arachnid lies a huge central young cluster of massive stars, cataloged as R136 and partially visible on the upper right.

APOD: 2023 August 22 Б The Pistachio Nebula
22.08.2023

This nebula had never been noted before. Newly discovered nebulas are usually angularly small and found by professionals using large telescopes. In contrast, the Pistachio Nebula was discovered by dedicated amateurs and, although faint, is nearly the size of the full Moon.

Leonid Fireball over Tenerife
22.11.2011

Historically active, this year's Leonid meteor shower was diminished by bright moonlight. Still, faithful night sky watchers did see the shower peak on November 18 and even the glare of moonlight didn't come close to masking this brilliant fireball meteor.

In the Center of the Heart Nebula
8.12.2004

What powers the Heart Nebula? The large emission nebula dubbed IC 1805 looks, in whole, like a human heart. The nebula glows brightly in red light emitted by its most prominent element: hydrogen. The red glow and the larger shape are all created by a small group of stars near the nebula's center.