A Desert Eclipse
13.01.2020

A good place to see a ring-of-fire eclipse, it seemed, would be from a desert. In a desert, there should be relatively few obscuring clouds and trees. Therefore late last December a group...

APOD: 2023 January 31 Б A Triple View of Comet ZTF
31.01.2023

Comet ZTF has a distinctive shape. The now bright comet visiting the inner Solar System has been showing not only a common dust tail, ion tail, and green gas coma, but also an uncommonly distinctive antitail.

APOD: 2025 January 27 Б Pleiades over Half Dome
27.01.2025

Stars come in bunches. The most famous bunch of stars on the sky is the Pleiades, a bright cluster that can be easily seen with the unaided eye. The Pleiades lies only about 450 light years away, formed about 100 million years ago, and will likely last about another 250 million years.

APOD: 2026 May 9 Б Messier Craters in Stereo
9.05.2026

Many bright nebulae and star clusters in planet Earth's sky are associated with the name of astronomer Charles Messier from his famous 18th century catalog. His name is also given to these two large and remarkable craters on the Moon.

Moon AND Stars
6.09.2001

Here's something you don't see too often ... a detailed picture of the full Moon surrounded by a rich field of background stars. It's true that bright moonlight scattered by the atmosphere...

Antennae Galaxies in Near Infrared
11.04.2002

What happens when galaxies collide? One of the best studied examples of the jumble of star clusters, gas, and dust clouds produced by such a cosmic train wreck is the interacting galaxy pair NGC 4038 / NGC 4039, the Antennae Galaxies, only sixty million light-years away.

X Ray Stars in the Orion Nebula
19.05.2005

When our middle-aged Sun was just a few million years old it was thousands of times brighter in x-rays. In fact, it was likely similar to some of the stars found in this false-color x-ray composite of the Orion Nebula region from the Chandra Observatory.

Infrared Andromeda
9.06.2006

This wide, detailed Spitzer Space Telescope view features infrared light from dust (red) and old stars (blue) in Andromeda, a massive spiral galaxy a mere 2.5 million light-years away. In fact, with over twice the diameter of our own Milky Way, Andromeda is the largest nearby galaxy.

Abell 2218: A Galaxy Cluster Lens
10.02.2008

Gravity can bend light, allowing huge clusters of galaxies to act as telescopes. Almost all of the bright objects in this Hubble Space Telescope image are galaxies in the cluster known as Abell 2218.

Phases of Venus
21.05.2020

Just as the Moon goes through phases, Venus' visible sunlit hemisphere waxes and wanes. This composite of backyard telescopic images illustrates the steady changes for Venus during its current stint as our evening star, as the inner planet grows larger but narrows to a thin crescent.