APOD 4.6

Aurora Over Raufarhöfn (April 30, 2012)

The Arctic Henge in northern Iceland points north toward the auroral lights pictured above.  By design, the apex of the Henge lines perfectly with the midnight sun at its highest point in the sky during the summer solstice in the northern hemisphere.  A midnight sun is a phenomenon that occurs in the northern latitudes of Earth, where the sun stays visible during the local midnight and stays risen for 24 hours.  The number of days this occurs changes from year to year.