Millions of Stars in Omega Centauri
16.04.2002

Pictured above is the largest ball of stars in our Galaxy. About 10 million stars orbit the center of this globular cluster - named Omega Centauri - as this giant globular cluster orbits our Galactic center.

APOD: 2025 June 21 Б Two Worlds, Two Analemmas
21.06.2025

Sure, that figure-8 shaped curve you get when you mark the position of the Sun in Earth's sky at the same time each day over one year is called an analemma.

A Delta Rocket Launches
13.12.1995

A Delta rocket is seen being launched in 1988. In use since 1960, Delta rockets have been launched successfully over 200 times. Scientific satellites placed into orbit by a Delta rocket include IUE, COBE, LAGEOS-I, ROSAT, EUVE, GEOTAIL, and WIND.

The First Explorer
18.05.1997

The first US spacecraft was Explorer 1. The cylindrical 30 pound satellite was launched (above) as the fourth stage of a Jupiter-C rocket (a modified US Army Redstone ballistic missile) and achieved orbit on January 31, 1958.

Phoebe: Comet Moon of Saturn
30.06.2004

Was Saturn's moon Phoebe once a comet? Images from the robotic Cassini spacecraft taken two weeks ago when entering the neighborhood of Saturn indicate that Phoebe may have originated in the outer Solar System.

Saturns Moon Rhea from Cassini
15.02.2005

Each moon of Saturn seems to come with its own mystery. Rhea, Saturn's second largest moon behind Titan, shows unusual wisps, visible above as light colored streaks. Higher resolution images of the wisps show them to be made of long braided fractures.

The Eagle Rises
25.07.2009

Get out your red/blue glasses and check out this remarkable stereo view from lunar orbit. Created from two photographs (AS11-44-6633, AS11-44-6634) taken by astronaut Michael Collins forty years ago during the 1969 Apollo...

Dragon over Central Park
5.06.2020

Still bathed in sunlight the International Space Station (ISS) arced through this Manhattan evening sky on May 30. Moving left to right, its bright trail was captured in this composite image with a series of 5 second long exposures.

APOD: 2026 July 6 Б Dueling Bands over the Atacama Desert
6.07.2026

What are these two bands in the sky? The more commonly seen band is on the left and is the central band of our Milky Way galaxy. Our Sun orbits in the disk of this spiral galaxy so that from inside, it appears as a band of comparable brightness all the way around the sky.

Oddities of Star Cluster NGC 6397
20.02.2002

One of these stars is blinking. This star, a member of globular cluster NGC 6397, is noteworthy not just because it blinks, but because it blinks so fast and because its companion star is so atypical.