The Galactic Center Radio Arc
3.04.2005

What causes this unusual structure near the center of our Galaxy? The long parallel rays slanting across the top of the above radio image are known collectively as the Galactic Center Radio Arc and jut straight out from the Galactic plane.

Supernova Remnant N132D in X Rays
13.09.1999

Thousands of years after a star explodes, an expanding remnant may still glow brightly. Such is the case with N132D, a supernova remnant located in the neighboring Large Magellanic Cloud galaxy. The expanding shell from this explosion now spans 80 light-years and has swept up about 600 Suns worth of mass.

M31: The Andromeda Galaxy
25.11.2006

Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it.

A Spectacular Sky Over the Grand Tetons
14.08.2007

Behold the breathtaking beauty of Earth and sky together. In the foreground is the Teton Mountain Range of Wyoming, USA. The Grand Tetons are a relatively isolated set of high peaks that are part of the Rocky Mountains.

The Galactic Center Radio Arc
27.04.2008

What causes this unusual structure near the center of our Galaxy? The long parallel rays slanting across the top of the above radio image are known collectively as the Galactic Center Radio Arc and jut straight out from the Galactic plane.

Retrograde Mars
13.06.2010

Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun.

A Waterspout in Florida
16.05.2020

What's happening over the water? Pictured here is one of the better images yet recorded of a waterspout, a type of tornado that occurs over water. Waterspouts are spinning columns of rising moist air that typically form over warm water.

M31: The Andromeda Galaxy
18.01.2022

The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy. Even at some two and a half million light-years distant, this immense spiral galaxy -- spanning over 200,000 light years -- is visible, although as a faint, nebulous cloud in the constellation Andromeda.

APOD: 2023 September 5 Б Blue Supermoon Beyond Syracuse
4.09.2023

The last full moon was doubly unusual. First of all, it was a blue moon. A modern definition of a blue moon is a second full moon to occur during one calendar month. Since there are 13 full moons in 2023, one month has to have two -- and that month was August.

W5: Pillars of Star Formation
15.12.2014

How do stars form? Images of the star forming region W5 like those in the infrared by NASA's Wide Field Infrared Survey Explorer (WISE) satellite provide clear clues with indications that massive stars near the center of empty cavities are older than stars near the edges.