Previous | Session 26 | Next | Author Index | Block Schedule
A. Saha (NOAO), D. Monet (USNO)
Continued acquisition and analysis for short-exposure observations support the preliminary conclusion presented by Monet et al. (BAAS v36, p1531, 2004) that a 10-second exposure in 1.0-arcsecond seeing can provide a differential astrometric accuracy of about 10 milliarcseconds. A single solution for mapping coefficients appears to be valid over spatial scales of up to 10 arcminutes, and this suggests that numerical processing can proceed on a per-sensor basis without the need to further divide the individual fields of view into several astrometric patches. Data from the Subaru public archive as well as from the LSST Cerro Pachon 2005 observing campaign and various CTIO and NOAO 4-meter engineering runs have been considered. Should these results be confirmed, the expected astrometric accuracy after 10 years of LSST observations should be around 1.0 milliarcseconds for parallax and 0.2 milliarcseconds/year for proper motions.
Previous | Session 26 | Next
Bulletin of the American Astronomical Society, 37 #4
© 2005. The American Astronomical Soceity.