Venus in the Moon
4.12.2008

On December 1, bright planets Venus and Jupiter gathered near the young crescent Moon, an inspiring celestial scene in early evening skies around the world. But from some locations the Moon actually passed in front of Venus, interrupting the tight grouping with a lunar occultation.

APOD Turns 17
16.06.2012

The first APOD appeared seventeen years ago today, on 1995 June 16. Although garnering only 14 page views on that day, we are proud to estimate that APOD has now served over one billion space-related images over the last 1.7 decades.

The SDSS 3D Universe Map
28.10.2003

The latest map of the cosmos again indicates that dark matter and dark energy dominate our universe. The Sloan Digital Sky Survey (SDSS) is on its way to measuring the distances to over one million galaxies.

NGC 2261: Hubble s Variable Nebula
8.11.2017

What causes Hubble's Variable Nebula to vary? The unusual nebula featured here changes its appearance noticeably in just a few weeks. Discovered over 200 years ago and subsequently cataloged as NGC 2661, the remarkable nebula is named for Edwin Hubble, who studied it early last century.

Perseids Around the Milky Way
17.08.2020

Why would meteor trails appear curved? The arcing effect arises only because the image artificially compresses (nearly) the whole sky into a rectangle. The meteors are from the Perseid Meteor Shower that peaked last week.

Gems of a Maldivean Night
28.03.2022

The southernmost part of the Milky Way contains not only the stars of the Southern Cross, but the closest star system to our Sun -- Alpha Centauri. The Southern Cross itself is topped by the bright, yellowish star Gamma Crucis.

Sagittarius Dwarf Irregular Galaxy
16.11.2004

How old is this galaxy? The nearby Local Group galaxy dubbed the Sagittarius Dwarf Irregular Galaxy (SagDIG) is not only very small but also has relatively few elements more massive than helium.

Inside Mars
23.03.2000

What's inside Mars? From orbit, the Mars Global Surveyor (MGS) spacecraft has recorded detailed images of the red planet since July 1997. Still, its cameras can not look beneath the surface. But minute...

Young Star, Dark Cloud
26.12.2003

High-speed outflows of molecular gas from a young stellar object glow in infrared light, revealing themselves in this recent false-color image from the Spitzer Space Telescope. Cataloged as HH (Herbig-Haro) 46/47 the infrared source...

Unusual Red Glow Over Minnesota
17.02.2009

What in heaven's blazes is that? When landing in Minneapolis, Minnesota, USA in 2002, just after his flight descended below cloud level in the early evening, passenger Tyler Blessing saw and photographed "huge...