WINTER BEGINS today, December 21, 2021, at 10:59 AM EST. This is the precise moment that the Sun reaches its maximum southern declination. At this moment, the Sun “stands” and reverses its apparent southerly motion and begins to head north again, as seen from a geocentric perspective. Winter begins for the northern hemisphere, and the days begin to grow longer… Continue reading


The Earth reaches its point of aphelion at July 4, 2020, 7:34 AM EDT. At this precise moment, the Earth is at its greatest distance from the Sun of any time of the year. This occurs in the summertime over the northern hemisphere. Some people mistakenly believe that summer is caused to the Earth being close to the Sun, but… Continue reading


THE SUMMER SOLSTICE: Today is the first day of summer for the northern hemisphere, the longest day of the year. On this day, the Sun reaches it’s maximum northern declination of the year. Thus, this day is the winter solstice for the southern hemisphere, the shortest day of the year for the lands south of the equator. For a detailed… Continue reading


SPRING BEGINS at 4:58PM EDT on March 20. This is the moment of the vernal equinox, when the Sun is centered on the celestial equator, where traditionally day and night are balanced. Some know-it-all types like to mention “equilux” instead of “equinox.” This is some newfangled pedantry that presumes to correct the traditional definition of “12 equal hours of day… Continue reading


WINTER SOLSTICE: Winter begins for the northern hemisphere on December 21 at 22:23 UT (5:23 PM EST). This is the precise moment when the Sun reaches its most southerly declination of the year. For this reason, December 21 is the shortest day of the year. As seen from the northern hemisphere, the noon Sun is lowest in the sky of… Continue reading


DAYLIGHT SAVINGS: It’s that time again! This Sunday, we all get back that extra hour of sleep that we lost back in the spring. At 2:00 AM Sunday morning, the clocks “fall back” an hour. Daylight Savings Time (DST) ends and we revert back to standard time. Enjoy that extra hour! But the evening darkness will now arrive early, which… Continue reading

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