Star Trails and the Bracewell Radio Sundial
13.07.2018

Sundials use the location of a shadow to measure the Earth's rotation and indicate the time of day. So it's fitting that this sundial, at the Very Large Array Radio Telescope Observatory in New Mexico, commemorates the history of radio astronomy and radio astronomy pioneer Ronald Bracewell.

The Ecliptic Plane
27.09.1997

The Plane of the Ecliptic is illustrated in this Clementine star tracker camera image which reveals (from right to left) the Moon lit by Earthshine, the Sun's corona rising over the Moon's dark limb, and the planets Saturn, Mars, and Mercury.

Aurora Over Iowa
18.12.2006

Last Thursday evening, stars were not the only lights in Iowa skies. Spectacular northern lights also shone from the heavens, extending across the midwestern USA and other locations not often graced with auroral displays.

Comet Holmes Over Hungary
5.12.2007

Comet Holmes refuses to fade. The unusual comet that surprisingly brightened nearly a million-fold in late October continues to remain visible to the unaided eye from dark locations. Night to night, Comet 17P/Holmes is slowly gliding through the constellation Perseus, remaining visible to northern observers during much of the night right from sunset.

Aurora Iowa
20.05.2005

Early last Sunday morning stars were not the only lights in Iowa skies. The northern lights also shone from the heavens, extending across the midwestern USA and other locations not often graced with auroral displays.

The Ecliptic Plane
21.09.1996

The Plane of the Ecliptic is illustrated in this Clementine star tracker camera image which reveals (from right to left) the Moon lit by Earthshine, the Sun's corona rising over the Moon's dark limb, and the planets Saturn, Mars, and Mercury.

APOD: 2023 August 6 Б SN 1006: A Supernova Ribbon from Hubble
6.08.2023

What created this unusual space ribbon? The answer: one of the most violent explosions ever witnessed by ancient humans. Back in the year 1006 AD, light reached Earth from a stellar explosion...

Flying over Planet Earth
27.09.2011

Have you ever dreamed of flying high above the Earth? Astronauts visiting the International Space Station do this every day, circling our restless planet twice every three hours. A dramatic example of their view was compiled in the above time-lapse video from images taken earlier this month.

APOD: 2023 January 25 Б LDN 1622: The Boogeyman Nebula
25.01.2023

To some, the dark shape looks like a mythical boogeyman. Scientifically, Lynds' Dark Nebula (LDN) 1622 appears against a faint background of glowing hydrogen gas only visible in long telescopic exposures of the region.

SGR 1900+14 : Magnetar
3.09.1998

On August 27th an intense flash of X-rays and gamma-rays swept through our Solar System. Five spacecraft of the Third InterPlanetary gamma-ray burst Network, Ulysses, WIND, RXTE, NEAR, and BeppoSAX, recorded the high energy...