The Montage Image Mosaic Service: Custom Mosaics on Demand

ESTO

John Good, Bruce Berriman

Mihseh Kong and

Anastasia Laity

IPAC, Caltech

http://hachi.ipac.caltech.edu:8080/montage

M51 2MASS J-band, 0.2 x 0.2 deg.Wall clock time 26s

What Is Montage?• Montage is a portable, scaleable toolkit for producing

science-grade image mosaics from input FITS images• Preserves astrometry and flux of input images

• Delivers mosaic according to users specifications

• Rectifies background radiation to a common level

• Utilities for, e.g., creating 3-color images & tiling images

• Code available for download at http://montage.ipac.caltech.edu• Over 300 downloads by astronomers

• In active use in supporting processing pipelines & data product generation, E/PO, quality assurance and science analysis

• Design: see Berriman et al. 2004, ASP Conf 314, ADASS XIII, 593; Berriman et al. 2003, ASP Conf 295, ADASS XII, 343

Ubeda and Pellerin 2007, Ap J Lett. 3-color IRAC images of GRSMC 45.453+0.060

Ogle et al 2007, Ap J. 3-color IRAC mosaic of 3C 326

Mosaic Service Front End

Data sets supported• 2MASS All Sky (IRSA)• SDSS DR6 (FermiLab)• DSS (Space Telescope)

Usage Restrictions for First Release• 1 deg on a side max• 10 simultaneous jobs• Results kept for 72 hours

Account set-upMonitoring Options

Wall clock time 184 s

http://hachi.ipac.caltech.edu:8080/montage

Job Control & Monitoring

Completed Jobs

Jobs Running.Statusrefreshed every15s

. . . and/or e-mail notification

Bookmark and return later . . .

Sample Results Page

Design Drivers for Mosaic Service• Cluster housed at IRSA/IPAC

• Rapid response and high throughput• Pathfinder for projects such as LSST

• Design Goals• Inexpensive, commodity hardware• Highly fault-tolerant• Scaleable, extensible and distributable• Portable, open source software• Modular software for maintainability & extensibility to other

applications• Hardware Choices

• 15 Xeon 3.2-GHz dual-processor dual-core (60 threads) Dell 2650 Power Edge servers

• Aberdeen Technologies 6-TB RAID-5 disk farm for staging files• Total Cost US$ 60K

Throughput Specifications• 15 Dual-processor dual-core compute nodes 60 simultaneous independent jobs. Throughput:• 15 square degrees of 2MASS mosaics a minute or

• 21,000 square degrees a day (arcsecond resolution) or

• Almost 2 TB of image data/day• Data transfer is ultimate performance limitation • Distributed processing overcomes this problem

Wall Clock Timing Comparisons - NGC 5584, 0.4 deg x 0.4 deg

2MASS-J 52 images 638 s

SDSS-g 8 images 184 s

DSS-R 1 image 166 s

System Architecture

Request Object Management Environment - Kong, Good and Berriman, ASP Conf Ser, 347, ADASS XIV, 213

Program Interface• Underlying ROME functionality is program-friendly by design; release wraps this with forms and HTML output for typical users. Prototype evaluated by AstrogridPrototype evaluated by Astrogrid. Functionality includes• Request authentication) and password, easily extended to use certificates, etc. • Polling, email notification, and asynchronous (socket) messages. • Requests / responses in HTML or XML; includes status information (such as job status filtering). • Asynchronous aborts. ROME Processors can allow for control input via socket (via requests through ROME server).

• Distributed, heterogenous operations. • Dedicated processing. Processors can limit the jobs to a specific applications or users

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Future Plans

• Upload table of sources• Building cutout/mosaics for multiple sources.

• User-defined WCS. • The service already supports arbitrary (user-supplied) FITS

headers but not deployed • Three-color images. • User data.

• By uploading a image list (URLs), the user can mosaic their own data or data lists from IVO SIA services.

• Standard plates. • Cutout from large (~5 degree) pre-built plates. A second cluster

is currently being set up to handle such "production” runs.

These upgrades require only wrappers around the “core” service