Vernal Equinox

Vernal Equinox: The Rite of Spring

As the cold and darkness of winter slowly fade into the past, brighter and warmer days are fast approaching - to the delight of many. While the weather may not show it, springtime officially begins on the Vernal Equinox, around the date of March 20th. The word equinox comes from Latin meaning "equal night" and it's on this day that light and dark appear to be about the same length- roughly a twelve hour long day and night.

Astronomically speaking the March equinox marks one of the four major turning points in the cycle of seasons for our planet. The Earth spins on its axis, which is tilted at an angle of 23.5 degrees with respect to it orbital plane. As our planet travels in it path around the Sun, the Earth's axis on the equinoxes (both March and September) is neither tilted away (winter) nor towards (summer) the Sun. And it's on these two days of the year that both northern and southern hemispheres are bathed in equal amounts of sunlight. While we in the northern hemisphere usher in spring this month, our counterparts in the southern hemisphere welcome autumn.

For skywatchers, the Sun has appeared to slowly creep ever higher in the mid day sky since the Winter Solstice in December. Now on the Vernal Equinox, the Sun reaches its halfway point in its seasonal journey towards its highest point in the sky - Summer Solstice in June. The Vernal equinox also marks the time when the sun appears to rise due east and set due west on your local horizon.

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• Now, I can see the difference!：Thanks, will sudty it! -一語湖邊_lakeshore- ♂ (0 bytes) () 03/23/2009 postreply 09:40:23