Venus Transits the Midnight Sun
20.06.2012

Today's solstice, the astronomical beginning of summer in the north, is at 23:09 UT when the Sun reaches the northernmost declination in its yearly trek through planet Earth's sky. While most...

Partial Eclipse, Cloudy Day
21.12.2001

Welcome to the December Solstice, first day of winter in the north and summer in the southern hemisphere of planet Earth. Today the Sun reaches its southernmost declination in the sky at 19:21 Universal Time.

Analemma of the Moon
13.07.2005

An analemma is that figure-8 curve you get when you mark the position of the Sun at the same time each day for one year. But the trick to imaging an analemma...

Solargraphic Analemmas
2.07.2022

For the northern hemisphere June 21 was the summer solstice, the Sun reaching its northernmost declination for the year. That would put it at the top of each of these three figure-8 curves, or analemmas, as it passed through the daytime sky over the village of Proboszczow, Poland.

The Andromeda Galaxy from GALEX
22.12.2003

Why does the Andromeda Galaxy have a giant ring? Viewed in ultraviolet light, the closet major galaxy to our Milky Way Galaxy looks more like a ring galaxy than a spiral. The ring...

APOD: 2020 August 5 Б Picture Rocks Sun Dagger
5.08.2020

Ancient sun daggers will not hurt you, but they may tell you the time.б A sun dagger is a dagger-shaped gap in a shadow created by sunlight streaming throughбa crevice in a nearby rock.

Extraordinary Solar Halos
21.12.2018

Welcome to the December Solstice, the first day of winter in planet Earth's northern hemisphere and summer in the south. To celebrate, consider this extraordinary display of beautiful solar ice halos! More common than rainbows, simple ice halos can be easy to spot, especially if you can shade your eyes from direct sunlight.

APOD: 2023 October 31 Б Halloween and the Wizard Nebula
31.10.2023

Halloween's origin is ancient and astronomical. Since the fifth century BC, Halloween has been celebrated as a cross-quarter day, a day halfway between an equinox (equal day / equal night) and a solstice (minimum day / maximum night in the northern hemisphere).

The View from Stereo Ahead
22.12.2006

On December 22nd, at 0022 Universal Time the Sun reached its southernmost point in Earth's sky marking the final season change for the year 2006. In celebration of the Solstice, consider these images of the Sun from an extreme ultraviolet telescope onboard the Stereo Ahead spacecraft.

Sunrise Analemma (with a little extra)
20.09.2012

An analemma is that figure-8 curve that you get when you mark the position of the Sun at the same time each day throughout planet Earth's year. In this case, 17 individual images...