About the MSUM Archive of the MAPS Catalog
The MSUM Archive of the Minnesota Automated Plate Scanner Catalog of the POSS I (hereafter "MAPS Catalog") is a project to provide an interactive version of the MAPS Catalog for the astronomical community. The project is the idea of Dr. Juan Cabanela, one of the former graduate students in the MAPS project and first author of the paper describing the "final" data release of the MAPS Catalog.
The goal of this project was not just to replicate the fine work of the MAPS project, but to extend it by tying in additional data and services. However, as I developed these new "extensions" to the original MAPS Catalog, the MAPS Project choose to implement these features back on their site, so today the two sites provide data that is virtually identical.
The features, first developed by Juan Cabanela for this archive include:
- Added J2000 and Galactic coordinates to all objects directly in the database computed using the same algorithms as the NASA Extragalactic Database (NED). This makes searches in J2000.0 and Galactic coordinates much, much quicker. [Added June 2004]
- Added estimates of Galactic extinction E(B-V) based on bilinear interpolation of extinction estimates from the dust maps from Schlegel, Finkbeiner, & Davis (1998). [Added June 2004]
- Indexed on all the coordinate positions (B1950, J2000, Galactic) as well as all magnitudes, diameters, and E(B-V). This provides much faster querying where these variables are concerned. [Added June 2004]
- Integrated links to other astronomical data sources to pull of images of the field you search and provide additional information about that field from other online catalogs. [Added June 2004]
- Added the POSS I plate information we have cataloged during the scanning of the POSS I fields, including:
- Astrometric fit parameters for each POSS I field
- Lists of which regions of each plate were cut due to flaring around bright sources, nebulousity, etc.
- Photometric calibration information on the stellar magnitude diameter to magnitude relation including the list of standards used to accomplish the diameter-to-magnitude fit on each plate.
- Photometric calibration information on the integrated magnitude density to intensity relation for each plate used to determined extended source magnitudes.
- Added downloading of the entire catalog in binary file format as well as providing errata to the original catalog. [Added July 2004]
- Added a Finder Chart Service which can properly handle B1950, J2000, and Galactic Coordinates near the poles and elsewhere on the sky. [Added August 2004]
- Corrected position angles presented in the database to the typical angle "east of north" definition. [Completed May 2005]
- Adding the ability to use "circular" bounds during a sky query, that is to pull up all the objects within a given angular separation of your field center. This has been implemented as a function in MySQL. Angular separation (in arcseconds) from the field center) is now an allowed output column. [Completed June 2005]
- Migration to PHP 5 and MySQL 5 [Beta version online on private server in January 2006, Completed Summer 2006 along with migration to MSUM]
- Matching of multiple user entered positions to MAPS Catalog [In development]