Charon: Moon of Pluto
3.06.2023

A darkened and mysterious north polar region known to some as Mordor Macula caps this premier high-resolution view. The portrait of Charon, Pluto's largest moon, was captured by New Horizons near the spacecraft's closest approach on July 14, 2015.

A Volcanic Great Conjunction
20.12.2020

Where can I see the Great Conjunction? Near where the Sun just set. Directionally, this close passing of Jupiter and Saturn will be toward the southwest. Since the planetary pair...

The Holographic Principle
30.04.2002

Is this image worth a thousand words? According to the Holographic Principle, the most amount of information you can get from this image is about 3 x 10⁶⁵ bits for a normal sized computer monitor.

Nix and Hydra
24.06.2006

Discovered in mid-2005, Pluto's small moons were provisionally designated S/2005 P1 and S/2005 P2. They have now been officially christened Nix and Hydra. Compared to Pluto and its large moon Charon...

Orbiting a Black Hole
1.07.2013

What would it look like to orbit a black hole? Since the strong gravity of the black hole can significantly alter light paths, conditions would indeed look strange. For one thing, the entire sky would be visible, since even stars behind the black hole would have their light bent to the observer's eye.

Colors of the Moon
15.05.2022

What color is the Moon? It depends on the night. Outside of the Earth's atmosphere, the dark Moon, which shines by reflected sunlight, appears a magnificently brown-tinged gray. Viewed from inside the Earth's atmosphere, though, the moon can appear quite different.

The Moon During a Total Lunar Eclipse
25.05.2021

How does the Moon's appearance change during a total lunar eclipse? The featured time-lapse video was digitally processed to keep the Moon bright and centered during the 5-hour eclipse of 2018 January 31. At first the full moon is visible because only a full moon can undergo a lunar eclipse.

Charon: Moon of Pluto
6.07.2018

A darkened and mysterious north polar region known to some as Mordor Macula caps this premier high-resolution view. The portrait of Charon, Pluto's largest moon, was captured by New Horizons near the spacecraft's closest approach on July 14, 2015.

Polaris and the Trail of Comet ZTF
3.02.2023

Stars trace concentric arcs around the North Celestial Pole in this three hour long night sky composite, recorded with a digital camera fixed to a tripod on January 31, near цger, Lleida, Spain. On that date Comet C/2022 E3 (ZTF) was near its northernmost declination in planet Earth's sky.

Comet McNaught Passes NGC 1245
17.06.2010

Of the many comets named for discoverer Robert McNaught, the one cataloged as C/2009 R1 is gracing dawn skies for northern hemisphere observers this month. Seen here on June 13th from southern New Mexico, this Comet McNaught's long ion tail sweeps across the telescopic field of view (a negative image is inset).