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| Mayan Calendar ends on 21.12.2012 |
The Mayan calendar is coming to an end and the frenzy on the internet and in books are just overwhelming.
The winter solstice is some kind of "passage" to the other side as well. The winter solstice occurs on the shortest day and longest night of the year, when the sun's daily maximum elevation in the sky is the lowest. Since the winter solstice lasts only a moment in time, other terms are often used for the day on which it occurs, such as "midwinter", "the longest night", "the shortest day" or "the first day of winter". The seasonal significance of the winter solstice is in the reversal of the gradual lengthening of nights and shortening of days.
Worldwide, interpretation of the event has varied from culture to culture, but most Northern Hemisphere cultures have held a recognition of rebirth, involving holidays, festivals, gatherings, rituals or other celebrations around that time.
Direct observation of the solstice by amateurs is difficult because the sun moves too slowly at either solstice to determine its specific day, let alone its instant. Knowledge of when the event occurs has only recently been facilitated to near its instant according to precise astronomical data tracking.
It is not possible to detect the actual instant of the solstice (by definition, one can not observe that an object has stopped moving until one makes a second observation in time showing that it has not moved further from the preceding spot, or that it has moved in the opposite direction). Further, to be precise to a single day one must be able to observe a change in azimuth or elevation less than or equal to about 1/60 of the angular diameter of the sun.
Observing that it occurred within a two day period is easier, requiring an observation precision of only about 1/16 of the angular diameter of the sun. Thus, many observations are of the day of the solstice rather than the instant. This is often done by watching the sunrise and sunset or vice versa or using an astronomically aligned instrument that allows a ray of light to cast on a certain point around that time.
Source: WikipediaDirect observation of the solstice by amateurs is difficult because the sun moves too slowly at either solstice to determine its specific day, let alone its instant. Knowledge of when the event occurs has only recently been facilitated to near its instant according to precise astronomical data tracking.
It is not possible to detect the actual instant of the solstice (by definition, one can not observe that an object has stopped moving until one makes a second observation in time showing that it has not moved further from the preceding spot, or that it has moved in the opposite direction). Further, to be precise to a single day one must be able to observe a change in azimuth or elevation less than or equal to about 1/60 of the angular diameter of the sun.
Observing that it occurred within a two day period is easier, requiring an observation precision of only about 1/16 of the angular diameter of the sun. Thus, many observations are of the day of the solstice rather than the instant. This is often done by watching the sunrise and sunset or vice versa or using an astronomically aligned instrument that allows a ray of light to cast on a certain point around that time.
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