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Abstract. We present Hubble Space Telescope/WFPC2 images of the galaxies NGC 2366, NGC 2976, NGC 4236, IC 2574, DDO 53, DDO 82, DDO 165, Holmberg I, Holmberg II, Holmberg IX, K52, K73, BK3N, Garland, and A0952+69 in the M 81 complex. Their true distance moduli, derived from the brightness of the tip of the red giant branch, lie in the range of 27. m 52 (NGC 2366) to 28. m 30 (DDO 165), with a median of 27. m 91, which is typical for other known M 81 group members. Using distances and radial velocities of about 50 galaxies in and around the M 81/NGC 2403 complex, we find the radius of the zero-velocity surface of the M 81 group to be R0 = (1.05 ± 0.07) Mpc, which yields a total mass M (R0) = (1.6 ± 0.3) × 10 12 M and a total mass-to-luminosity ratio M (R0)/LB = (38 ± 7) M /L . The total mass within R0 agrees well with the sum of masses estimated via the virial theorem (1.2 × 10 12 M ) and from orbital motions (2.0 × 10 12 M ) of companions around M 81 and NGC 2403. We suggest that most of the dark matter in the group is concentrated around the luminous matter, allowing us to explain the observed asymmetry of the peculiar motions of the M 81 companions. M 81 itself has a peculiar velocity of about 130 km s −1 with respect to the local Hubble flow, but the centroid of the M 81/NGC 2403 complex is almost at rest with respect to Hubble flow (vpec < 35 km s −1 ).

Abstract.We present an analysis of Hubble Space Telescope/WFPC2 images of nine nearby galaxies in Sculptor. We derive their distances from the luminosity of the tip of the red giant branch stars with a typical accuracy of ∼12%.

Abstract. We present Hubble Space Telescope/WFPC2 images of seventeen dwarf galaxies in the Centaurus A group. Their distances derived from the magnitudes of the tip of the red giant branch are 5.2 Mpc (KK112),

Ultraviolet-to-visual spectra of eight young star clusters in the merger remnant and protoelliptical galaxy NGC 7252, obtained with the 4 m Blanco Telescope on Cerro Tololo, are presented. These clusters lie at projected distances of 3È15 kpc from the center and move with a velocity dispersion of 140^35 km s~1 in the line of sight. Seven of the clusters show strong Balmer absorption lines in their spectra [EW(Hb) \ 6È13 while the eighth lies in a giant H II region and shows no detectable absorp-A ], tion features. Based on comparisons with model cluster spectra computed by Bruzual & Charlot and Bressan, Chiosi, & Tantalo, six of the absorption-line clusters have ages in the narrow range of 400È600 Myr, indicating that they formed early in the recent merger. These clusters, and probably also the seventh absorption-line cluster, are globular clusters, as judged by their small e †ective radii and ages corresponding to D102 core crossing times. The one emission-line object is Myr old and may be a [10 nascent globular cluster or an OB association. The mean metallicities measured for three clusters are solar to within about^0.15 dex, suggesting that the merger of two likely Sc galaxies in NGC 7252 formed a globular cluster system with a bimodal metallicity distribution. Since NGC 7252 itself shows the characteristics of a 0.5È1 Gyr old protoelliptical galaxy, its second-generation solar-metallicity globular clusters provide direct evidence that giant elliptical galaxies with bimodal globular cluster systems can form through major mergers of gas-rich disk galaxies. A puzzling property of the observed young globular clusters are the high masses of (1È35)M(u Cen) implied by their luminosities and ages (for an assumed Salpeter IMF). A spectrum of a candidate superluminous globular cluster in the elliptical galaxy NGC 1700, obtained with the Hiltner Telescope at MDM Observatory, shows this object to be a foreground star.

Abstract. We present Hubble Space Telescope/WFPC2 images of eighteen galaxies situated in the vicinity of the Local Group (LG) as part of an ongoing snapshot survey of nearby galaxies. Their distances derived from the magnitude of the tip of the red giant branch are 1.92 ± 0.10 Mpc (ESO 294-010), 3.06 ± 0.37 (NGC 404), 3.15 ± 0.32 (UGCA 105), 1.36 ± 0.07 (Sex B), 1.33 ± 0.08 (NGC 3109), 2.64 ± 0.21 (UGC 6817), 2.86 ± 0.14 (KDG 90), 2.27 ± 0.19 (IC 3104), 2.54 ± 0.17 (UGC 7577), 2.56 ± 0.15 (UGC 8508), 3.01 ± 0.29 (UGC 8651), 2.61±0.16 (KKH 86), 2.79±0.26 (UGC 9240), 1.11±0.07 (SagDIG), 0.94±0.04 (DDO 210), 2.07±0.18 (IC 5152), 2.23 ± 0.15 (UGCA 438), and 2.45 ± 0.13 (KKH 98). Based on the velocity-distance data for 36 nearest galaxies around the LG, we find the radius of the zero-velocity surface of the LG to be R0 = (0.94±0.10) Mpc, which yields a total mass MLG = (1.3 ± 0.3) × 10 12 M . The galaxy distribution around the LG reveals a Local Minivoid which does not contain any galaxy brighter than MV = −11 mag within a volume of ∼100 Mpc 3 . The local Hubble flow seems to be very cold, having a one-dimensional mean random motion of ∼30 km s −1 . The best-fit value of the local Hubble parameter is 73 ± 15 km s −1 Mpc −1 . The luminosity function for the nearby field galaxies is far less steep than one for members of the nearest groups.

For a sample of some 400 red giants in the chemically inhomogeneous globular cluster q Centauri, we report correlations between the radial velocities of Mayor et al., which are accurate to Շ1 km s Ϫ1 , and the calcium abundances of Norris et al., which have internal accuracy of 0.06 dex. We find that the 20% metal-rich tail of the [CaZH] distribution, as well as being more centrally concentrated, is kinematically cooler than the 80% metalpoorer component. At first glance one might interpret this as evidence consistent with a dissipative enrichment scenario of cluster formation. It obtains, however, that while the metal-poorer component exhibits well-defined systemic rotation, the metal-richer one shows no evidence of it, in contradistinction to the simple dissipative picture. A more natural explanation of the observed rotation and other chemical abundance data is provided by the globular cluster binary merger calculations of Makino et al., in the context of merging within the fragments first postulated by Searle.