Les Montagiers

1. An Astronomical Image Mosaic Service for theNational Virtual Observatoryhttp://montage.ipac.caltech.edu

2. Bruce Berriman IPAC Attila Bergou JPL Ewa Deelman ISI John Good IPAC Joseph Jacob JPL Daniel Katz JPL Carl Kesselman ISI Anastasia Laity IPAC Thomas Prince Caltech Gurmeet Singh ISI Mei-Hui Su ISI Roy Williams CACR Les Montagiers

3. What is Montage? • Delivers custom, science grade image mosaics • User specifies projection, coordinates, spatial sampling, mosaic size, image rotation • Preserve astrometry & flux • Modular “toolbox” design • Loosely-coupled Engines for Image Reprojection, Background Removal, Co-addition • Control testing and maintenance costs • Flexibility; e.g custom background algorithm; use as a reprojection and co-registration engine • Implemented in ANSI C for portability • Public service will be deployed on the Teragrid • Order mosaics through web portal

4. Public Release of Montage • Version 1.7.1 available for download at http://montage.ipac.caltech.edu • User’s Guide including caveats • Emphasizes accuracy in photometry and astrometry • Images processed serially • Tested and validated on 2MASS 2IDR images on Linux Red Hat 8.0 (Kernel release 2.4.18-14) on a 32-b it processor • Tested on 10 WCS projections with mosaics smaller than 2 x 2 degrees and coordinate transformations Equ J2000 to Galactic and Ecliptic • Code metrics • 20 modules; 7560 Lines of code • 2595 test cases executed; 119 defects reported and 116 corrected

5. Applications of Montage • GLIMPSE SIRTF Legacy Team • Large scale infrared mosaics of the Galactic Plane • Co-registration of 2MASS J, H, K and MSX 8 m images • Quality Assurance of GLIMPSE SIRTF data

6. Applications of Montage • SWIRE SIRTF Legacy team • Wide area of imaging survey of high galactic latitude fields • Evolution of stellar populations up to z=3 • Co-registration of 2MASS and SIRTF Infrared Array Camera (IRAC) images • Simulations, mission planning & pipeline testing

7. E/PO “Cool Cosmos” • http://coolcosmos.ipac.caltech.edu/ • Montage generates image mosaics at a single color • Photoshop used to combine them into multi-color images

8. Montage: The Grid Years • Re-projection is slow (100 seconds for one 1024 x 512 pixels 2MASS image, single processor 1.4 GHz Linux box), so use parallelization inherent in design • Grid is an abstraction - array of processors, grid of clusters, … • Montage has modular design - run on any environment • Prototype architecture for ordering a mosaic through a web portal • Request processed on a computing grid • Prototype uses the USC-ISI/Wisconsin Grid • In operations will use the Distributed Terascale Facility (“The Teragrid”)

9. Montage: The Grid Years cont • Prototype version of a methodology for running on any “grid environment” • Many parts of the process can be parallelized • Build a script - directed acyclical graph (DAG) - that enables parallelization • Describes flow of data and processing • Describes which data are needed by which part of the job • Describes what is to be run and when • DAG is submitted to standard tools for execution

10. Example: Build a Mosaic of M101 2MASS 2IDR Images 1.5 degrees on a side; 100 images

11. M101 Mosaic: 2MASS J band

12. 3 3 2 2 1 3 2 1 1 Final Mosaic mProject 1 mProject 2 mProject 3 mAdd mBackground 1 mBackground 2 mBackground 3 mDiff 1 2 mDiff 2 3 mFitplane D12 mFitplane D23 mBgModel DAG for Montage D23 D12 a1x + b1y + c1 = 0 a2x + b2y + c2 = 0 a3x + b3y + c3 = 0 ax + by + c = 0 dx + ey + f = 0

13. Montage on the Grid Maps an abstract workflow to an executable form Pegasus Montage Workflow Specification (abstract) Grid Information Systems Information about available resources, data location Condor DAGMan Executes the workflow Grid

14. Summary • Version 1.7.1 released • Serial processing • Used or adapted by Atlasmaker, SWIRE, GLIMPSE, IPAC E/PO • Developing grid architecture • Prototype version exploiting parallelization in Montage design • Operational version Spring 2004