Beaver Street, October 2008
The Harvest Moon and Jupiter greet us into the fall season
Midnight, September 23, 2010, Waltham
The vernal and autumnal equinoxes occur when the sun is moving directly between the north and south poles, right along the celestial equator*, giving us a day of approximately half daylight and half darkness. It is from this point until the December solstice that the northern hemisphere will experience increasingly less daylight. Of course, it's just the opposite for those living in the southern hemisphere; today marks their vernal (spring) equinox, in which their days will continue to "grow longer" until the December solstice!
Earth image by NASA; diagram constructed by Dennis Nilsson (2007).
*The celestial equator is an imaginary circle around earth in space; it parallels the terrestrial (Earth's) equator, inclined 23.4 degrees to the ecliptic plane due to our planet's axial tilt.
Did you know: the full moon closest to the autumnal equinox is called the harvest moon?
The Harvest Moon and Jupiter greet us into the fall seasonMidnight, September 23, 2010, Waltham
The vernal and autumnal equinoxes occur when the sun is moving directly between the north and south poles, right along the celestial equator*, giving us a day of approximately half daylight and half darkness. It is from this point until the December solstice that the northern hemisphere will experience increasingly less daylight. Of course, it's just the opposite for those living in the southern hemisphere; today marks their vernal (spring) equinox, in which their days will continue to "grow longer" until the December solstice!
Earth image by NASA; diagram constructed by Dennis Nilsson (2007).*The celestial equator is an imaginary circle around earth in space; it parallels the terrestrial (Earth's) equator, inclined 23.4 degrees to the ecliptic plane due to our planet's axial tilt.
Did you know: the full moon closest to the autumnal equinox is called the harvest moon?
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