The 88 constellations as defined by the IAU segment the sky into regions,
separated by an intricate set of boundaries. A binary tree decomposition of
this landscape is given which tessellates the celestial sphere into rectangles.
This allows a fast determination of the constellation membership of any given
sky coordinate.Comment: 4 pages, 1 figur

Glaschke, Patrick

English

arXiv

The 88 constellations as defined by the IAU segment the sky into regions, separated by an intricate set of boundaries. A binary tree decomposition of this landscape is given which tessellates the celestial sphere into rectangles. This allows a fast determination of the constellation membership of any given sky coordinate. Key words: constellations – binary tree Determining the constellation membership of a celestial coordinate is a tedious task: Though the constellation boundaries follow lines of constant declination and right ascension at epoch B1850.0, they take a winding course over the sky to assure consistency with older membership definitions of various sky objects. A first step beyond the brute-force check of every constellation is a search in a boundary set ordered by declination and right ascension. Roman [2] has prepared such a data table which allows the user to stop the identification process as soon as a positive detection has occurred without processing the remaining constellations. However, the worst case still requires an exhaustive search with a total amount of more than 1,000 coordinate comparisons. This might be prohibitive if 

Fast Determination of Constellation Membership

Abstract

Similar works

Full text

Available Versions

CiteSeerX