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Timekeeping and Calendars


Astronomical Firsts June 10, 2010

Radio Programs

Dog Days The dog days of summer August 13, 2016

Imperial Month The “imperial” months of summer August 1, 2016

Ides of March Beware the Ides of March March 15, 2016

Leap Day Leaping with the seasons February 29, 2016

Moon and Regulus Marking the rhythms of the sky February 21, 2016

To the Future! Traveling into the future February 18, 2016

Arrow of Time Going forward in time February 16, 2016

Big Dipper Clock Ticking off the hours of the night January 22, 2016

September Equinox Changing seasons — one way or another September 21, 2015

Moon and Antares Ticking off the hours of the night September 18, 2015

Lammas Splitting the difference on the calendar July 31, 2015

Leap Second Stretching out the month of June June 29, 2015

Canopus III Navigating by a bright star February 23, 2015

Moon and Mars Jet lag after a long trip November 24, 2014

Daylight Saving Time Saving daylight to save energy October 31, 2014

Star Time Setting your watch by the stars October 20, 2014

Autumnal Equinox One way to mark a change in seasons September 21, 2014

July Honoring a famous calendar maker June 30, 2013

Winter Solstice A changing calendar cycle December 20, 2012

Moon and Companions Nothing to fear in the morning sky December 7, 2012

Seventh Month Miscounting the months August 31, 2012

Relativity and GPS Keeping track of the entire world May 7, 2012

Leap Day Leaping into the modern calendar February 28, 2012

The New Year Bringing the calendar to heel December 31, 2011

Saturnalia A modern celebration with old customs December 16, 2011

Daylight Saving Time Stepping back in time November 5, 2011

Changing Time Just passing the time October 17, 2011

Calendars Following the cycles of the sky September 22, 2011

Moon and Jupiter An ancient god and the modern calendar September 14, 2011

April Springing into a beautiful month March 31, 2011

Moon and Saturn A timely companion for the Moon March 18, 2011

February Counting up the days of February January 31, 2011

Featured Images

Postcard of the historic Elgin Watch Company Observatory in Illinois

Star Time October 25, 2014

Without Einstein's theories of relativity, GPS wouldn't work

Where Am I? May 8, 2012