Spring Equinox 2015 Brings Celestial Hat Trick

Friday, March 20, 2015, marks a unique coincidence of events for stargazers everywhere. March 20 is the Spring Equinox, a day when the plane of the equator passes the center of the sun. This essentially means that both day and night are of almost equal length, signifying a changing of the seasons. Throughout history, the equinoxes (roughly March 20 and September 22) have inspired hundreds of harvesting festivals and holidays. Some of the most notable holidays in America centered around the Spring Equinox are Easter and Passover, with Easter being set as the first Sunday after the first full moon on or after the equinox. Since the Eastern Orthodox Churches use the Julian Calendar, which list the equinox as March 22, the earliest day Easter can be held on is March 22 in these traditions, regardless of the celestial occurrence. The first day of Passover, on the other hand, is held on the first full moon after the equinox.

This year the equinox will coincide with two other significant celestial events: a solar eclipse and supermoon. A solar eclipse is the advent of the moon’s passing between the sun and the earth, obscuring the sun’s light completely for a particular region of the world, and partially for other locations. Unfortunately, this solar eclipse will not be visible for North America, with only a remote Northern European island chain seeing the full effects of the eclipse Friday morning. Europe, Northern Africa, and most of Asia will have a partial viewing. The last total solar eclipse happened on November 3, 2013.

A supermoon occurs when a new or full moon are showing during the moon’s closest approach to earth’s orbit. This means that the moon will look particularly massive, and will be the closest it will ever be (under normal circumstances) to earth’s orbit. This supermoon will be a new moon, so it won’t be visible, excepting those locations that will get to see the eclipse. The last supermoon was on September 9, 2014. These three rare events won’t occur on the same day again until March 20, 2039.