The Case of the Missing Star
6.06.2017

What's happened to giant star N6946-BH1? It was there just a few years ago -- Hubble imaged it. Now there's only a faint glow. What's curiouser, no bright supernova occurred -- although the star did brightened significantly for a few months.

Mimas: Small Moon with a Big Crater
21.10.2014

Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn's smallest moons. The crater, named Herschel after the 1789 discoverer of Mimas, Sir William Herschel, spans about 130 kilometers and is pictured above.

Zubenelgenubi and Friends
14.05.2004

Moderately bright Zubenelgenubi is the star just off the upper right hand limb of an eclipsed Moon in this telescopic view from Port Elizabeth, South Africa. Actually the second brightest star in the constellation...

Cassini To Venus
16.10.1997

NASA's Saturn Explorer Cassini with ESA's Titan Probe Huygens attached successfully rocketed into the skies early yesterday morning. The mighty Titan 4B Centaur rocket is seen here across the water gracefully arcing away from Launch Complex 40 at Cape Canaveral Air Station.

A Higher Dimensional Universe
18.03.2007

Does our universe have higher but unusual spatial dimensions? This idea has been gaining popularity to help explain why vastly separated parts of our universe appear so similar, and why the geometry of our universe does not seem to result naturally from the amounts of matter it seems to contain.

Prometheus Creating Saturn Ring Streamers
27.04.2009

What's causing those strange dark streaks in the rings of Saturn? Prometheus. Specifically, an orbital dance involving Saturn's moon Prometheus keeps creating unusual light and dark streamers in the F-Ring of Saturn. Now Prometheus orbits Saturn just inside the thin F-ring, but ventures into its inner edge about every 15 hours.

Rosetta Approaches Asteroid Lutitea
24.04.2012

What would it look like to approach an asteroid in a spaceship? In 2010, ESA's robotic Rosetta spacecraft zipped past the asteroid 21 Lutetia taking data and snapping images in an effort to better determine the history of the asteroid and the origin of its unusual colors.

Two Black Holes Merge
12.02.2016

Just press play to watch two black holes merge. Inspired by the first direct detection of gravitational waves by LIGO, this simulation video plays in slow motion but would take about one third of a second if run in real time.

APOD: 2023 July 17 Б Shells and Arcs around Star CW Leonis
17.07.2023

What's happening around this star? No one is sure. CW Leonis is the closest carbon star, a star that appears orange because of atmospheric carbon dispersed from interior nuclear fusion. But CW Leonis also appears engulfed in a gaseous carbon-rich nebula.

The Blue Snowball Planetary Nebula
21.11.1996

Will the Sun one day look like - a blue snowball? Maybe! The Blue Snowball is a planetary nebula - and in 5 billion years the Sun will throw off its outer layers and go through a planetary nebula phase.