Chapter 19: Web-based tools-montage: An astronomical image mosaic engine

Montage (http://montage.ipac.caltech.edu) is a toolkit for aggregating astronomical images into mosaics. Its scientific value derives from three features of its design: • It preserves the calibration and astrometric fidelity of the input images to deliver mosaics that meet user-specified parameters of projection, coordinates, and spatial scale. It supports all projections and coordinate systems in use in astronomy. • It contains independent modules for analyzing the geometry of images on the sky, and for creating and managing mosaics; these modules are powerful tools in their own right and have applicability outside mosaic production, in areas such as data validation. It can take advantage of SIAP services to discover input images that meet the specifications of the sky coverage of the output mosaic. • It is written in ANSI-compliant C, and is portable and scaleable – the same engine runs on desktop, cluster or supercomputer environments running common Unix-based operating systems such as Linux, Solaris, Mac OS X and AIX.