Oxford University Press, Monthly Notices of the Royal Astronomical Society, 3(303), p. 565-574, 1999
DOI: 10.1046/j.1365-8711.1999.02233.x
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Data is presented which extends the sample of quasi-stellar objects (QSOs) behind the southern satellite galaxies of the Milky Way. These objects were sought for use as unresolved, inertial reference objects in proper motion studies of Milky Way satellite galaxies. Key words: quasars: general -- galaxies: Local Group 1 INTRODUCTION Advances in CCD astrometry from the ground have demonstrated the feasibility of milli-arcsecond (mas) precision relative astrometry at faint magnitudes (Dahn 1997; Tinney 1995). This means that short-term observing programs (510 years) can now measure proper motions as small as 0.1mas/yr for faint targets. This is precisely the sort of precision required to measure the absolute space motions of the Milky Way (MW) satellite galaxies. Such an observing program, however, requires unresolved, background reference objects -- ie. quasi-stellar objects (QSOs) . Unfortunately, very few QSOs suitable for this purpose exist in the literature. Tinney, Da Costa & Zinn...