Astrognosia
The Astrognosie (from the Greek "star knowledge") is the historical name for the study of the arrangement of celestial bodies and asterisms ( constellations ) in the night sky that one with the naked eye can see, including the planets and the names of the individual objects.
The field of activity includes:
- the division of the starry sky into a set of constellations - today a selection of 88 different asterisms is used
- The determination of the affiliation of fixed stars to the constellations plays a role especially in the astronomical nomenclature of star naming with Greek letters and constellations
- the representation of the constellation borders on star maps and by projection of the starry sky in a planetarium
- the free-eyed observation of falling stars and the paths of fireballs .
This subject area is to be seen as a sub-area of the taxonomy of astronomy , which developed the basis for the systematics of astronomical phenomenology and observational astronomy .
Astrognosy stands next to the other classic fields of astronomy: Researching the physical properties ( astrophysics ) , as well as the intrinsic movements ( astrometry ) of the stars, and calculating the star locations and positions of the celestial bodies ( celestial mechanics , ephemeris calculation ) .
In the historical astronomy is also concerned with the developments of today's constellations and asterisms that have been used in other cultures (or outside the modern international astronomy today find use). One also works with archaeoastronomy and the calendar system , since the figures in the starry sky form the basis of earlier historical celestial calendars .
From a historical perspective, astrognosia also forms a basis for astrology , which deals with the possible influence of the stars.
Astrognosia and Sphere
For many tasks of astrognosy a good knowledge of the spheres - especially the celestial coordinates - is required: z. B. for the definition of constellation borders, the assignment of cometary words or the exact documentation of the orbits of bright meteors .
In today's training of astronomers these topics are practically not dealt with, often not even spherical astronomy . This shortcoming was already criticized by Oswald Thomas at an astronomical congress in 1932 , but little has changed. The topic is most likely to be dealt with in geodesy courses .
The founder of the Austrian Astronomical Association and doyen of modern meteor astronomy commented on its necessity, especially in the documentation of comet and meteor orbits , as follows:
“Astrognosia, together with the so-called“ elementary ”[…], also including spherics and astronomical geography, forms the stepchild of astronomy - completely wrongly and to the detriment of science. With this in mind, I made a recommendation to the IAU on September 5, 1932 [...]: 'The progress of scientific meteor astronomy ultimately depends just as much on the quality of the available meteorological reports as the results when calculating comets on the quality of the telescopic determinations . The usefulness of reports about fireballs depends directly on the extent to which the casual observers (mostly non-astronomers) are familiar with the constellations and elementary spherical terms'. Capturing lay reports profitably via a fireball is an impossibility without astrognostic mastery of the sphere. Unfortunately, there has been little interest in general astronomical subjects among the audience at our university in recent years. "
Web links
- Physical Dictionary: Astrognosia, Star Knowledge
Individual evidence
- ^ Oswald Thomas on astrognosia in 100 years of astronomical office . H. Mucke 2007 ( astroverein.at ).