An equinox is either of the two moments in the year when the sun is exactly over the Equator and the day and night are exactly the same length. Both solstices and equinoxes are simply stages of Earth’s orbit around the sun.

On December 21 we entered the winter solstice in the northern hemisphere, the shortest day of the year and we are moving towards the spring equinox, around March 21, after the summer solstice on June 21, finally the autumnal equinox, about Sept. 23, and then winter solstice again.

The spring equinox, which in the western hemisphere coincides with the start of the season of the same name, is about March 21 when the sun moves northward over the line of Equator.

The autumnal equinox occurs around September 23 when the sun crosses the Equator in its movement south. The exact time of equinox varies each year because of leap years.

The ruins of Chichen Itza archeological site and Dzibilchaltún are the two best places to appreciate the equinox. This is an archaeo-astronomical phenomenon, where Earth is illuminated by the sun the same way in the northern hemisphere and in the south.

On the evening of 21 March and 22 September during the spring and fall equinoxes, respectively, there is a solar projection consisting of seven triangles of light, inverted, as a result of the shadow of the nine platforms of the pyramid, at sunset, simulating the image of a snake down through the banisters of the stairs of the north staircase of the Kukulcan Pyramid or El Castillo at Chichen Itza.

This phenomenon of light simulates a snake descending majestically through the banisters of the stairs of the Kukulcan Pyramid at Chichen Itza. The first shadows of the pyramid begins to draw isosceles triangles that make up the body of the feathered serpent that seems to move slowly downward until the head of the snake reaches bottom of the balustrade.

When the last of the triangle reaches the base of the balustrade, all spectators stand up and raise their hands to absorb the positive energy that emanates from this phenomenon. All this process takes approximately 45 minutes.

Click on http://bestcancundeals.com if you want to know about hotels in Cancun and tours to Chichen Itza.