We present the first results of a ground-based program to determine the proper motion of the Magellanic Clouds (MCs) relative to background quasars (QSO), being carried out using the Iréneé du Pont 2.5 m telescope at Las Campanas Observatory, Chile. Eleven QSO fields have been targeted in the Small Magellanic Cloud (SMC) over a time base of six years, and with seven epochs of observation. One quasar field was targeted in the Large Magellanic Cloud (LMC), over a time base of five years, and with six epochs of observation. The shorter time base in the case of the LMC is compensated by the much larger amount of high-quality astrometry frames that could be secured for the LMC quasar field (124 frames), compared to the SMC fields (an average of roughly 45 frames). In this paper, we present final results for field Q0557-6713 in the LMC and field Q0036-7227 in the SMC. From field Q0557-6713, we have obtained a measured proper motion of //,, cos S = +1.95 ± 0.13 mas yr 1, //j = +0.43 ± 0.18 mas yr 1 for the LMC. From field Q0036-7227, we have obtained a measured proper motion of n" cosS = +0.95 ± 0.29 mas yr 1. p¡ =-1.14 ± 0.18 mas yr 1 for the SMC. Although we went through the full procedure for another SMC field (QJ0036-7225), on account of unsolvable astrometric difficulties caused by blending of the QSO image, it was impossible to derive a reliable proper motion. Current model rotation curves for the plane of the LMC indicate that the rotational velocity (Trot) at the position of LMC field Q0557-6713 can be as low as 50 km s', or as high as 120 km s'. A correction for perspective and rotation effects leads to a center of mass proper motion for the LMC of cosS = +1.82 ± 0.13 mas yr /u = +0.39 ± 0.15 mas yr 1 (Vrot = 50 km s'), and to nL, cosS = +1.61 ± 0.13 mas yr = +0.60 ± 0.15 mas yr 1 (Vrot = 120 km s©). Assuming that the SMC has a disk-like central structure, but that it does not rotate, we obtain a center of mass proper motion for the SMC of /tu cosS = +1.03 ± 0.29 mas yr ps =-1.09 ± 0.18 mas yr© Our results are in reasonable agreement with most previous determinations of the proper motion of the MCs, including recent Hubble Space Telescope measurements. Complemented with published values of the radial velocity of the centers of the LMC and SMC, we have used our proper motions to derive the galactocentric (gc) velocity components of the MCs. For

Photoelectric and CCD UBV survey data are presented for stars brighter than about in V ∼ 16.5 the field of the faint Carina Wolf-Rayet (WR) stars WR 38 and WR 38a. Both WR stars appear to belong to an associated compact cluster (nuclear diameter ∼0Ј .3) of at least six faint OB stars reddened by E p 1.60 ‫ע‬ BϪV s.e. and lying at a distance of ∼ kpc ( s.d.). As cluster members, the 0.02 14.5 ‫ע‬ 1.6 V Ϫ M p 15.80 ‫ע‬ 0.25 0 V two WR stars have estimated luminosities of (WR 38, type WC4) and (WR 38a, type M p Ϫ5.8 M p Ϫ5.0 v v WN5). The former value is slightly more luminous than expected for Galactic WR stars.

We report the confirmation of an old, metal-poor globular cluster in the nearby dwarf irregular galaxy Sextans A, the first globular cluster known in this galaxy. The cluster, which we designate as Sextans A-GC1, lies some 4.4 arcminutes (∼ 1.8 kpc) to the SW of the galaxy centre and clearly resolves into stars in sub-arcsecond seeing groundbased imaging. We measure an integrated magnitude V = 18.04, corresponding to an absolute magnitude, M V,0 = −7.85. This gives an inferred mass M ∼1.6×10 5 M , assuming a Kroupa IMF. An integrated spectrum of Sextans A-GC1 reveals a heliocentric radial velocity v helio = 305 ± 15 km s −1 , consistent with the systemic velocity of Sextans A. The location of candidate red giant branch stars in the cluster, and stellar population analyses of the cluster's integrated optical spectrum, suggests a metallicity [Fe/H] ∼-2.4, and an age ∼ 9 Gyr. We measure a half light radius, R h = 7.6 ± 0.2 pc. Normalising to the galaxy integrated magnitude, we obtain a V-band specific frequency, S N = 2.1. We compile a sample of 1,928 GCs in 28 galaxies with spectroscopic metallicities and find that the low metallicity of Sextans A-GC1 is close to a "metallicity floor" at [Fe/H] ∼-2.5 seen in these globular cluster systems which include the Milky Way, M31, M87 and the Large Magellanic Cloud. This metallicity floor appears to hold across 6 dex in host galaxy stellar mass and is seen in galaxies with and without accreted GC subpopulations.

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