Zodiacal Light and Mars
11.03.2021

Just after sunset on March 7, a faint band of light still reaches above the western horizon in this serene, rural Illinois, night skyscape. Taken from an old farmstead, the luminous glow is zodiacal light, prominent in the west after sunset during planet Earth's northern hemisphere spring.

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.

APOD: 2024 October 21 Б Comet Tsuchinshan ATLAS over California
21.10.2024

The tails of Comet Tsuchinshan-ATLAS were a sight to behold. Pictured, C/2023 A3 (TsuchinshanБATLAS) was captured near peak impressiveness last week over the Eastern Sierra Mountains in California, USA. The comet not only showed a bright tail, but a distinct anti-tail pointing in nearly the opposite direction.

Austrian Analemma
22.09.2012

Today, the Sun crosses the celestial equator heading south at 14:49 Universal Time. An equinox (equal night), this astronomical event marks the first day of autumn in the northern hemisphere and spring in the south.

Equinox: The Sun from Solstice to Solstice
23.09.2019

Today is an equinox, a date when day and night are equal. Tomorrow, and every day until the next equinox, the night will be longer than the day in Earth's northern hemisphere, and the day will be longer than the night in Earth's southern hemisphere.

Star Trails Over Vienna
14.07.2005

As the Earth spins on its axis, the sky seems to rotate around us. This motion, called diurnal motion, produces the beautiful concentric trails traced by stars during time exposures. In the middle...

Aurora Oklahoma
13.11.2003

Nestled in the central US, the state of Oklahoma is noted for its gorgeous prairie skies and wide-open spaces, but not for frequent visitations of the northern lights. Still, following the intense solar activity...

Lunation Matrix
1.10.2022

Observe the Moon every night and you'll see its visible sunlit portion gradually change. In phases progressing from New Moon to Full Moon to New Moon again, a lunar cycle or lunation is completed in about 29.5 days.

Apollo s Analemma
22.09.2013

Today, the Sun crosses the celestial equator heading south at 20:44 Universal Time. An equinox (equal night), this astronomical event marks the first day of autumn in the northern hemisphere and spring in the south.

Great Refractor and Lunar Eclipse
26.11.2021

Rain clouds passed and the dome of the Lick Observatory's 36 inch Great Refractor opened on November 19. The historic telescope was pointed toward a partially eclipsed Moon. Illuminated by dim red lighting...