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We present the results of a spectro- scopic and photometric investigation of 18 probable members of the open cluster Collinder 220, which contains the Cepheid UW Car. Besides the Cepheid, we studied tree K-giants, two B-giants, and twelve B-A-F main sequence stars. Radial velocities (RV), vsini, T eff , and logg were determined using spec- troscopic model fitting and atmosphere models. We have derived color-excesses, reddenings, and intrinsic colors for these stars using their T eff and logg from comparison to the atmosphere models, especially for hot stars. Proper motions, RV, and the GAIA DR2 2018 parallaxes allowed us to determine their membership in the cluster and absolute magnitudes. We found that seven stars along with the Cepheid can be the cluster members with a high confidence. The parallaxes and reddenings of the 7 confident cluster members led to the distances in a range of 1900–2800 pc, while the other stars are probably foreground objects. All the members have [Fe/H] near 0.1 dex. The B-giant HD90435 located near the cluster’s “turn-off” point has a low projected rotational veloc- ity, and this fact allows us to determine its chemical composition to compare with that of the Cepheid UW Car. The CNO abundances of HD90435 are nearly solar, while the Cepheid shows a deficit of carbon, an overabundance of nitrogen, a nearly solar oxygen, and an overabundance of sodium. The confident cluster member, K-supergiant CPD −57 ◦ 3199, has CNO- and Na abundances close to those of UW Car.

We present the SALT spectroscopy of a globular cluster in the center of the nearby isolated dSph galaxy KKs3 situated at a distance of 2.12 Mpc. Its heliocentric radial velocity is 316+-7 km/s that corresponds to V_{LG} = 112 km/s in the Local Group (LG) reference frame. We use its distance and velocity along with the data on other 35 field galaxies in the proximity of the LG to trace the local Hubble flow. Some basic properties of the local field galaxies: their morphology, absolute magnitudes, average surface brightnesses, specific star formation rates, and hydrogen mass-to-stellar mass ratios are briefly discussed. Surprisingly, the sample of the neighboring isolated galaxies displays no signs of compression under the influence of the expanding Local Void., Comment: 12 pages, 6 figures, 1 table, accepted in the Astronomische Nachrichten

By combining new long-slit spectral data obtained with the Southern African Large Telescope (SALT) for 9 galaxies with previously published our observations for additional 12 galaxies we study the stellar and gaseous kinematics as well as radially resolved stellar population properties and ionized gas metallicity and excitation for a sample of isolated lenticular galaxies. We have found that there is no particular time frame of formation for the isolated lenticular galaxies: the mean stellar ages of the bulges and disks are distributed between 1 and > 13 Gyr, and the bulge and the disk in every galaxy formed synchronously demonstrating similar stellar ages and magnesium-to-iron ratios. Extended ionized-gas disks are found in the majority of the isolated lenticular galaxies, in 72%$\pm$11%. The half of all extended gaseous disks demonstrate visible counterrotation with respect to their stellar counterparts. We argue that just such fraction of projected counterrotation is expected if all the gas in isolated lenticular galaxies is accreted from outside, under the assumption of isotropically distributed external sources. A very narrow range of the gas oxygen abundances found by us for the outer ionized gas disks excited by young stars, [O/H] from 0.0 to +0.2 dex, gives evidence for the satellite merging as the most probable source of this accretion. At last we formulate a hypothesis that morphological type of a field disk galaxy is completely determined by the outer cold-gas accretion regime., 25 pages, 11 figures and appendix consisted of 9 figures. Accepted for publication in the AJ

This paper describes the Third Data Release of the Sloan Digital Sky Survey (SDSS). This release, containing data taken up through 2003 June, includes imaging data in five bands over 5282 deg², photometric and astrometric catalogs of the 141 million objects detected in these imaging data, and spectra of 528,640 objects selected over 4188 deg². The pipelines analyzing both images and spectroscopy are unchanged from those used in our Second Data Release.

The Sloan Digital Sky Survey (SDSS) has validated and made publicly available its Second Data Release. This data release consists of 3324 deg² of five-band (ugriz) imaging data with photometry for over 88 million unique objects, 367,360 spectra of galaxies, quasars, stars, and calibrating blank sky patches selected over 2627 deg² of this area, and tables of measured parameters from these data. The imaging data reach a depth of r ≈ 22.2 (95% completeness limit for point sources) and are photometrically and astrometrically calibrated to 2% rms and 100 mas rms per coordinate, respectively. The imaging data have all been processed through a new version of the SDSS imaging pipeline, in which the most important improvement since the last data release is fixing an error in the model fits to each object. The result is that model magnitudes are now a good proxy for point-spread function magnitudes for point sources, and Petrosian magnitudes for extended sources. The spectroscopy extends from 3800 to 9200 Å at a resolution of 2000. The spectroscopic software now repairs a systematic error in the radial velocities of certain types of stars and has substantially improved spectrophotometry. All data included in the SDSS Early Data Release and First Data Release are reprocessed with the improved pipelines and included in the Second Data Release. Further characteristics of the data are described, as are the data products themselves and the tools for accessing them.

We present Multiple Mirror Telescope (MMT) spectrophotometry and 3.5m Calar Alto telescope R, I photometry of the western component of the extremely low-metallicity blue compact galaxy SBS 0335-052. We argue that both components, separated by 24 kpc, are members of an unique, physically connected system. It is shown that SBS 0335-052W has the same redshift as SBS 0335-052 and has an extremely low oxygen abundance, 12 + log (O/H) = 7.45+-0.22, comparable to those in I Zw 18 and SBS 0335--052. The (R-I) color profiles are very blue in both galaxies due to the combined effect of ionized gas and a young stellar population. We argue that SBS 0335--052W is likely to be a nearby young dwarf galaxy with age not exceeding 10^8 yr. The implications of this conclusion to the question of galaxy formation and to the properties of primeval dwarf galaxies are discussed., Comment: 18 pages and 2 Postscript figures, uses aasms4.sty. Submitted to Astrophysical Journal Letters

The Blue Compact Dwarf (BCD) galaxy SBS 0335--052 is one of the most metal--deficient galaxies known and one of the best candidates for a young dwarf galaxy in the process of formation. A VLA HI map reveals an unusual structure: the neutral gas is distributed in a very extended disk, about 15 times larger than the Holmberg optical diameter of the BCG. There are two peaks of high density. The eastern peak is close to the position of SBS 0335--052 whereas the western HI peak is associated with a faint compact optical galaxy. A 6--m telescope spectrum of this object shows Halpha, Hbeta, and [OIII] 5007 emission with a redshift close to that of SBS 0335--052. We suggest that it may be a young and chemically unevolved dwarf galaxy., Comment: 6 pages with 2 Postscript figures inside