|Photograph by David Mercado, Reuters|
Today, the sun crosses the celestial equator heading south. The moment of crossing or "solstice" occurs at 7:09 pm EDT and marks the beginning of northern summer. This is the longest day and shortest night of the year in the Northern Hemisphere. Meanwhile In the Southern Hemisphere, winter begins. Happy solstice!
Indian New Year via National Geographic
Bolivian indigenous people celebrate sunrise (above) during a winter solstice ceremony in Tiwanaku, about 44 miles (70 kilometers) from the capital of La Paz, on Monday (solstice 2010). In the Southern Hemisphere, the June solstice is the first day of winter, since that part of Earth is tilted farthest from the sun. The winter solstice coincides with the start of the New Year for South America's Aymara Indians.
|Photo by Rijk-Jan Koppejan|
To commemorate the 2012 summer solstice, astronomer Rijk-Jan Koppejan has made an image (above) of the sun--with an exposure time of six months. Every day from Dec. 2011 to June 2012, he used a solargraph to record the sun's motion across the skies of his observatory in Middelburg, the Netherlands.
A solargraph is a simple pinhole camera made from a soda or beer can lined with a piece of photographic paper. Koppejan deployed his solargraph in time to record last December's solstice (the lowest track in the image) and let it continue passively recording until June 19, 2012.