Ikeya Zhang: Comet Over Colorado
4.04.2002

Comet Ikeya-Zhang ("ee-KAY-uh JONG") has become a most photogenic comet. This lovely early evening view of the comet in Rocky Mountain skies looks northwest over ridges and low clouds. The time exposure was recorded on March 31st from an 8,000 foot elevation near Yampa, Colorado, USA.

Tempel Tuttle: The Leonid Comet
16.11.2002

Star trails streak this composite time exposure of comet Tempel-Tuttle recorded by Tim Puckett on January 26, 1998. Then passing through the inner solar system on its 33 year orbit around the Sun, Tempel-Tuttle brightened unexpectedly, but binoculars or small telescopes were still required to visually observe it.

Atmospheres Detected on Two Extrasolar Planets
27.02.2007

Do extrasolar planets have water? In an attempt to find out, the orbiting Spitzer Space Telescope made detailed observations of the atmospheres of two planets that orbit stars other than our Sun. Unfortunately, water vapor was not detected in either exoplanet.

A Flight through the Hubble Ultra Deep Field
27.08.2013

What would it look like to fly through the distant universe? To find out, a team of astronomers estimated the relative distances to over 5,000 galaxies in one of the most distant fields of galaxies ever imaged: the Hubble Ultra Deep Field (HUDF).

Dueling Bands in the Night
27.02.2018

What are these two bands in the sky? The more commonly seen band is the one on the right and is the central band of our Milky Way galaxy. Our Sun orbits...

Our Rotating Earth
1.07.2020

Has your world ever turned upside-down? It would happen every day if you stay fixed to the stars. Most time-lapse videos of the night sky show the stars and sky moving above a steady Earth.

Supernova in NGC 2525
23.10.2020

Big, beautiful, barred spiral galaxy NGC 2525 lies 70 million light-years from the Milky Way. It shines in Earth's night sky within the boundaries of the southern constellation Puppis. About 60,000 light-years...

The Andromeda Galaxy in Ultraviolet
18.07.2021

What does the Andromeda galaxy look like in ultraviolet light? Young blue stars circling the galactic center dominate. A mere 2.5 million light-years away, the Andromeda Galaxy, also known as M31, really is just next door as large galaxies go.

APOD: 2024 December 9 Б Pleiades: The Seven Sisters Star Cluster
9.12.2024

Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as large and clear as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen with the unaided eye even from the depths of a light-polluted city.

Melting Snow and the Gullies of Mars
21.02.2003

Tantalizing images of gullies on Mars have offered striking evidence for recent flows of liquid water. But Mars is too cold and its atmosphere too thin for liquid water to exist on the surface.