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MOC - HEALPix Multi-Order Coverage map
Version 1.0

IVOA Recommendation 02 June 2014

Interest/Working Group:
Thomas Boch, Tom Donaldson, Daniel Durand, Pierre Fernique, Wil O'Mullane, Martin Reinecke, Mark Taylor
Pierre Fernique


This document describes the Multi-Order Coverage map method (MOC) to specify arbitrary sky regions. The goal is to be able to provide a very fast comparison mechanism between coverage maps. The mechanism is based on the HEALPix sky tessellation algorithm. It is essentially a simple way to map regions of the sky into hierarchically grouped predefined cells.

Status of this document

This document has been produced by the Applications Interest Group.
It has been reviewed by IVOA Members and other interested parties, and has been endorsed by the IVOA Executive Committee as an IVOA Recommendation. It is a stable document and may be used as reference material or cited as a normative reference from another document. IVOA's role in making the Recommendation is to draw attention to the specification and to promote its widespread deployment. This enhances the functionality and interoperability inside the Astronomical Community.

Available formats: PDF, ODT

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