Title:
Automated calibration, or generating and trusting astronomical meta-data

Abstract:
We have built a reliable and robust system that takes as input an
astronomical image, and returns as output the pointing, scale, and
orientation of that image (the astrometric calibration or WCS
information).  The system uses computer vision techniques; it
requires no first guess, and works with the information in the image
pixels alone.  The success rate is better than 99.9 percent for
contemporary near-ultraviolet and visual imaging survey data, with no
false positives.  We can also calibrate (at low accuracy) the date at
which the image was taken, the bandpass, and the photometric
sensitivity.  We are using this system to generate consistent and
standards-compliant meta-data for all digital and digitized
astronomical imaging, no matter what its archival state, including
imaging from plate repositories, individual scientific investigators,
and amateurs.  This is necessary for worldwide systems like the
"virtual observatory" that depend on reliable meta-data but have no
explicit trust model.  For us it is the first step in a program of
making all of the world's heterogeneous astronomical imaging data
interoperable.