Constellations

In modern astronomy constellations are areas on which a celestial sphere parts for comfort of orientation on star sky. In antiquity constellations were name characteristic figures, formed bright stars.

In three-dimensional space there are most stars which we see alongside with each other, can be located very far from each other, but on a celestial sphere to be close. From the most ancient times people saw some system in the mutual location of stars and grouped them in accordance with it in constellations. And now people are not stopped by any difficulties on a way to that better to consider constellations: Travel visa, long travel, the unfamiliar countries and....

During history observers selected the different number of constellations and their outline, and the origin of some ancient constellations is not found out to the end. To XIX century under constellations reserved not areas of sky, but groups of stars which was quite often recovered, were understood. It turned out that some stars had belonged to two constellations at once, and some poor stars areas did not behave to some constellation. At the beginning of XIX century borders were conducted between constellations, liquidating «emptinesses» between constellations, however their much clear determination still was not, and different astronomers determined them their own way.

In 1922 in Rome by the decision of the Ist General assembly of the International astronomic union a list from 88 constellations was finally ratified, which star sky was divided by, and clear and simple scopes between these constellations, conducted strictly on the circles of direct ascents and declinations of the equatorial system of co-ordinates on an epoch 1875, were accepted in 1930. During five years clarifications were brought in in the scopes of constellations. In 1935 scopes were finally ratified and will not change anymore. However, should remember that on star maps, made for epoches, not consilient with an epoch 1875, in particular, all modern maps, from the precession of earthly axis of borders of constellations moved and already does not coincide with the circles of direct ascents and declinations.

From 88 constellations only 47 are ancient, known western civilization already a few millenniums. They are based mainly on mythology of Ancient Greece and engulf the area of sky, accessible to the supervisions from the south of Europe. Other modern constellations were entered in XVII—XVIII centuries as a result of study of South sky (in the epoch of the great geographical openings) and filling of «blank spaces» on north sky. The names of these constellations, as a rule, do not have mythological roots.

12 constellations traditionally named zodiacal — it's those which a Sun passes through (except constellation of Ophiucus).

posted by Admin on Oktober , 2008

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