Solargraphy Analemmas . ... The Sun crosses the celestial equator heading north at 16:57 UT, marking the northern hemisphere's first day of spring. ... In fact, three analemma curves were captured using a cylindrical pinhole camera by daily making three, separate, one minute long exposures for a year, from March 1, 2013 to March 1, 2014, on a single piece of black and white photographic paper. ... NASA Web Site Statements, Warnings, and Disclaimers . NASA Official: Jay Norris. ...