We present new medium-band uvby Strömgren and broadband VI photometry for the central regions of the globular cluster ω Cen. From this photometry we have obtained differential reddening estimates relative to two other globular clusters (M13 and NGC 288) using a metallicity-independent, reddening-free temperature index, [c]≡(u-v)-(v-b)-0.2(b-y), for

An analysis of 50 optical spectra of the interstellar methylidyne ion in the direction of HD26676 and HD149038 derived very similar interstellar isotopic ratios for the two lines-of-sight. A lack of a Galactic gradient in isotopic ratios is noted which is consistent with the location in the solar vicinity of the gas in front of HD149038. The

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We use Gaia Data Release 2 proper motions of field OB stars from the Runaways and Isolated O-Type Star Spectroscopic Survey of the Small Magellanic Cloud (SMC) to study the kinematics of runaway stars. The data reveal that the SMC Wing has a systemic peculiar motion relative to the SMC Bar of ({v}α ,{v}δ ) =(62+/- 7,-18+/- 5) {km} {{{s}}}-1 and

We have studied the core morphology of the ultraluminous infrared galaxy Mrk 273 by combining a high-resolution adaptive optics near-infrared image with an optical image from the Hubble Space Telescope and interferometric radio continuum data, all at spatial resolutions of 150 mas or better. The near-infrared image reveals that the nucleus has two

We present high spectral and spatial resolution spectroscopy of the nuclear starburst region of the galaxy NGC 253. Two slit positions, matching the major and minor axes on the galaxy, have been taken. These cover H-alpha and (N II) lines as well as the (S II) doublet. The attained resolution, together with good seeing conditions, have allowed the