The 2012 Autumnal Equinox occurs on September 22, at 7:49 a.m. PDT (14:49 Universal Time).
In the Northern Hemisphere, the sun is rising later now, and nightfall comes sooner. The time of the autumn equinox is here, when the days are getting shorter, and day and night are approximately equal in length.
For us in the Northern Hemisphere, people are enjoying the cooler days of autumn even as preparations for winter are underway. South of the equator, spring begins.
This is truly awe-inspiring.
Astronomy Photographer of the Year 2012
Fireflies dancing beneath the stars, the last transit of Venus for 105 years and giant swirling galaxies deep in space. The 2012 Astronomy Photographer of the Year competition has produced some awe-inspiring images.
Take a journey through the night sky with two of the nine judges - Chris Lintott who is best known as co-presenter of the BBC's The Sky at Night, and Olivia Johnson from the Royal Observatory Greenwich.