GRO J1655 40: Evidence for a Spinning Black Hole
1.06.2003

In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole. Studies of the bright light emitted by the swirling gas frequently indicate not only that a black hole is present, but also likely attributes.

Hale-Bopp's Fickle Ion Tail
14.05.1997

What's happening to Comet Hale-Bopp's blue ion tail? The comet's ion tail is fluctuating more rapidly as it passes a region of changing solar wind. As the comet passes from north to south, it crosses the plane of the Sun's equator, where the solar magnetic field changes direction.

Pluto: The Frozen Planet
13.02.1999

This portrait of Pluto and its companion Charon was taken by the Hubble Space Telescope in 1994. Pluto is usually the most distant planet from the Sun but because of its eccentric orbit Pluto crossed inside of Neptune's orbit in 1979.

The View Near a Black Hole
19.04.2009

In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole. Studies of the bright light emitted by the swirling gas frequently indicate not only that a black hole is present, but also likely attributes.

Dawn s Grande Finale
4.06.2011

After more than a month, the lovely lineup of four naked-eye planets in dawn skies is coming to a close. Still, on May 31st a slender Moon joined the grouping along the eastern horizon for a final celestial performance, presented in this early morning scene from a beach near Buenos Aires, Argentina.

A Circumhorizontal Arc Over Ohio
24.05.2014

Why would clouds appear to be different colors? The reason here is that ice crystals in distant cirrus clouds are acting like little floating prisms. Sometimes known as a fire rainbow for its flame-like appearance, a circumhorizon arc lies parallel to the horizon.

Nova over Thailand
21.11.2016

A nova in Sagittarius is bright enough to see with binoculars. Detected last month, the stellar explosion even approached the limit of naked-eye visibility last week. A classical nova results from a thermonuclear explosion...

APOD: 2023 November 29 Б A Landspout Tornado over Kansas
29.11.2023

Could there be a tornado inside another tornado? In general, no. OK, but could there be a tornado inside a wider dust devil? No again, for one reason because tornados comes down from the sky, but dust devils rise up from the ground.

APOD: 2025 July 11 Б The Veins of Heaven
11.07.2025

Transfusing sunlight as the sky grew darker, this exceptional display of noctilucent clouds was captured on July 10, reflected in the calm waters of Vallentuna Lake near Stockholm, Sweden. From the edge of space...

In the Center of 30 Doradus
4.10.1997

In the center of 30 Doradus lies a huge cluster of the largest, hottest, most massive stars known. The center of this cluster, known as R136, is boxed in the upper right portion of the above picture.