|This article needs additional citations for verification. (December 2014)|
|Genre||Astronomy-related events and competitions|
|Date(s)||Saturday between mid-April and mid-May on or just before the first quarter moon|
|Participants||Astronomers and astronomy enthusiasts|
Astronomy Day is an annual event in the United States intended to provide a means of interaction between the general public and various astronomy enthusiasts, groups and professionals.
This event was started in 1973 by Doug Berger, the president of the Astronomical Association of Northern California. His intent was to set up various telescopes in busy urban locations so that passersby could enjoys views of the heavens. Since then the event has expanded and is now sponsored by a number of organizations associated with astronomy.
Astronomy Day also forms part of National Astronomy Week, which begins on the preceding Monday.
Originally, Astronomy Day occurred on a Saturday between mid-April and mid-May, and was scheduled so as to occur at or close to the first quarter Moon. In 2007, an autumn rendition of Astronomy Day was added. It was scheduled to occur on a Saturday between mid-September and mid-October so as to be on or close to the first quarter Moon.
The lunar influence on the schedule means that the events happen on a different date each year, rather than set calendar dates. The table below shows the dates for Astronomy Day:
|Year||Season||Astronomy Day||First Quarter Moon|
|2005||Spring||April 16||April 16|
|2006||Spring||May 6||May 5|
|2007||Spring||April 21||April 24|
|2008||Spring||May 10||May 12|
|2009||Spring||May 2||May 1|
|2010||Spring||April 24||April 21|
|Fall||October 16||October 14|
|2011||Spring||May 7||May 10|
|Fall||October 1||October 3|
|2012||Spring||April 28||April 30|
|Fall||October 20||October 21|
|2013||Spring||April 20||April 18|
|Fall||October 13||October 11|
|2014||Spring||May 10||May 7|
|Fall||October 4||October 1|
|2015||Spring||April 25||April 25|
- Astronomical League information page on Astronomy Day
- Royal Astronomical Society of Canada - Astronomy Day
- Editors of Sky and Telescope;"Celebrate Astronomy Day". Sky And Telescope:April 28, 2012