The Iron Sun
25.09.2004

The ultraviolet light emitted by eleven times ionized iron at temperatures over 2 million degrees Farenheit was used to record the above picture of the Sun on September 22, 2001, the date of that year's autumnal equinox.

Messier Marathon
18.03.1999

Gripped by an astronomical spring fever, this week many amateur stargazers embark on a Messier Marathon. The Vernal Equinox occurs Saturday, March 20, marking the first day of Spring for the Northern Hemisphere.

APOD: 2023 June 21 Б Three Sun Paths
21.06.2023

Does the Sun follow the same path every day? No. The Sun's path changes during the year, tracing a longer route during the summer than the winter. Pictured here...

Triple Sunrise
23.09.2006

Today, the Sun rises due east at the Equinox, a geocentric astronomical event that occurs twice a year. To celebrate, consider this view of the rising Sun and a lovely set of ice halos recorded on a cold winter morning near Green Bay, Wisconsin, USA, planet Earth.

Zodiacal Light Vs. Milky Way
20.03.2010

Ghostly Zodiacal light, featured near the center of this remarkable panorama, is produced as sunlight is scattered by dust in the Solar System's ecliptic plane. In the weeks surrounding the March equinox (today...

A Martian Autumn Begins
23.09.1997

Today is the first day of Autumn in the Northern Hemisphere of Planet Earth. The Autumnal Equinox occured yesterday at 7:56 pm EDT as the Sun crossed the celestial equator from North to South.

Analemma over Taipei
21.06.2022

Does the Sun return to the same spot on the sky every day? No. A better and more visual answer to that question is an analemma, a composite of images taken at the same time and from the same place over the course of a year.

The New Moon in the Old Moon s Arms
24.03.2012

Also known as the Moon's ashen glow, Earthshine is Earthlight illuminating the Moon's night side. Taken on Nowruz, the March 20 equinox, from Esfahan, Iran, planet Earth, this telescopic image captures strong Earthshine from an old Moon. The darker earthlit disk is in the arms of a bright sunlit crescent.

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.

Blue Danube Analemma
29.07.2016

The Sun's annual waltz through planet Earth's sky forms a graceful curve known as an analemma. The analemma's figure 8 shape is tipped vertically at far right in this well-composed fisheye view from Budapest, Hungary.