Neptune through Adaptive Optics
18.02.2000

From the Earth's surface, Neptune usually appears as a fuzzy blotch. The blurring effects of the Earth's atmosphere deny clearer images. By distorting mirrors in the telescope itself in time with the changing atmosphere, however, these effects can be greatly reduced.

A Manhattan Sunset
28.05.2004

Today, if it is clear, Manhattan will flood dramatically with sunlight just as the Sun sets precisely on the centerline of every street. Usually, the tall buildings that line the gridded streets of New York City's tallest borough will hide the setting Sun.

Sunset at the Portara
20.03.2009

Today, the Sun crosses the celestial equator heading north at 11:44 UT. Known as an equinox, this astronomical event marks the first day of spring in the northern hemisphere and autumn in the south. It also marks the beginning of Norouz, the Persian (Iranian) new year. Equinox means equal night.

Sunrise Analemma
20.03.2003

Astronomically speaking, at the Equinox on March 21, 01:00 UT (March 20, 8:00 PM ET) the season changes. For this Equinox the Sun rises due east as it crosses the celestial equator heading north. In celebration, consider this spectacular sunrise analemma!

S is for Sun
21.03.2002

Taken yesterday from the SOHO spacecraft, this false-color image shows the active Sun near the March Equinox, the beginning of Fall in the south and Spring in the northern hemisphere. Recorded in a band...

Uranus Moon 18
31.05.1999

The discovery was there for the taking. An image of Uranus taken by Voyager 2 as it passed the giant planet 13 years ago apparently recorded a moon that had since gone unnoticed. The image on which Uranus' 18th moon was discovered was freely available from NASA. Erich Karkoschka (U.

Uranus's Moon Oberon: Impact World
8.04.1996

Oberon is the most distant and second largest moon of Uranus. Discovered by William Herschel in 1787, the properties of the world remained relatively unknown until the robot spacecraft Voyager 2 passed it during its flyby of Uranus in January 1986.

Miranda, Chevron, and Alonso
6.03.1999

Miranda is a bizarre world which surely had a tempestuous past. The innermost of the larger Uranian moons, Miranda is almost 300 miles in diameter and was discovered in 1948 by American planetary astronomer Gerard Kuiper.

Hamlet of Oberon
27.02.1999

What's in a name? Since 1919, the International Astronomical Union has been charged with the task of establishing "conventional" nomenclature for planets, satellites, and surface features. For the remote Uranian system of moons, namesakes from Shakespearean works have been chosen.

Miranda, Chevron, and Alonso
16.02.2002

Miranda is a bizarre world which surely had a tempestuous past. The innermost of the larger Uranian moons, Miranda is almost 300 miles in diameter and was discovered on today's date in 1948 by American planetary astronomer Gerard Kuiper.