Dust Sculptures in the Rosette Nebula
6.06.2007

What creates the cosmic dust sculptures in the Rosette Nebula? Noted for the common beauty of its overall shape, parts of the Rosette Nebula, also known as NGC 2244, show beauty even when viewed up close.

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.

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.

NGC 6814: Grand Design Spiral Galaxy from Hubble
20.06.2016

In the center of this serene stellar swirl is likely a harrowing black-hole beast. The surrounding swirl sweeps around billions of stars which are highlighted by the brightest and bluest. The breadth and beauty of the display give the swirl the designation of a grand design spiral galaxy.

Dark Dust and Colorful Clouds near Antares
26.08.2019

Why is the sky near Antares and Rho Ophiuchi so dusty yet colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae.

Electric Night
3.12.2019

It may appear, at first, like the Galaxy is producing the lightning, but really it's the Earth. The featured nighttime landscape was taken from a southern tip of the Italian Island of Sardinia in early June.

NGC 1365: Majestic Island Universe
21.12.2022

Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the faint but heated constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax Cluster of galaxies.

APOD: 2023 August 23 Б The Meteor and the Galaxy
22.08.2023

It came from outer space. It -- in this case a sand-sized bit of a comet nucleus -- was likely ejected many years ago from Sun-orbiting Comet Swift-Tuttle, but then continued to orbit the Sun alone.

APOD: 2024 December 22 Б The Local Fluff
21.12.2024

The stars are not alone. In the disk of our Milky Way Galaxy, about 10 percent of visible matter is in the form of gas called the interstellar medium (ISM). The ISM is not uniform and shows patchiness even near our Sun.

A Quasar Portrait Gallery
8.03.2002

Quasars (QUASi-stellAR objects) lie near the edge of the observable Universe. Discovered in 1963, astronomers were astounded that such objects could be visible across billions of light-years, as this implies they must emit prodigious amounts of energy. Where does the energy come from?