Utopia on Mars
22.07.1996

The Viking 2 spacecraft was launched on the Road to Utopia in September of 1975 (30 years after Bing, Dotty, and Bob). In August of 1976, after making the second successful Martian landing, Viking...

Hubble Floats Free
5.03.1997

Why put observatories in space? Most telescopes are on the ground. On the ground, you can deploy a heavier telescope and upgrade it more easily. The trouble is that Earth-bound telescopes must look through the Earth's atmosphere.

Kepler s SNR from Chandra, Hubble, Spitzer
8.10.2004

Light from the stellar explosion that created this energized cosmic cloud was first seen on planet Earth in October 1604, a mere four hundred years ago. The supernova produced a bright new star in early 17th century skies within the constellation Ophiucus.

A Mysterious Hexagonal Cloud System on Saturn
3.04.2007

Why would clouds form a hexagon on Saturn? Nobody is yet sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System.

Thackerays Globules
27.12.2008

Rich star fields and glowing hydrogen gas silhouette dense, opaque clouds of interstellar gas and dust in this Hubble Space Telescope close-up of IC 2944, a bright star forming region in Centaurus, 5,900 light-years away. The largest of these dark globules, first spotted by South African astronomer A. D.

Signals of a Strange Universe
28.03.2009

Eleven years ago results were first presented indicating that most of the energy in our universe is not in stars or galaxies but is tied to space itself. In the language of cosmologists, a large cosmological constant is directly implied by new distant supernovae observations.

The Solar System from MESSENGER
22.02.2011

If you looked out from the center of the Solar System, what would you see? Nearly such a view was taken recently from the MESSENGER spacecraft currently orbiting the Sun from the distance of Mercury. The Sun's planets all appear as points of light, with the closest and largest planets appearing the brightest.

Seasonal Dark Streaks on Mars
8.08.2011

What is causing these dark streaks on Mars? A leading hypothesis is flowing -- but quickly evaporating -- water. The streaks, visible in dark brown near the image center, appear in the Martian spring and summer but fade in the winter months, only to reappear again the next summer.

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.

Seyferts Sextet
10.12.2013

What will survive this battle of the galaxies? Known as Seyfert's Sextet, this intriguing group of galaxies lies in the head portion of the split constellation of the Snake (Serpens). The sextet actually contains only four interacting galaxies, though.