Finding distances in astronomy is notoriously difficult. With accurate optical spectroscopy, both the distance to and extinction (reddening) of normal stars can be found, but this is not possible for X-ray sources. It is possible, however, to measure the extincting column from an X-ray spectrum from photoelectric ionisation edges. It is also

The line-of-sight velocities and [O III] 5007 Å expansion velocities are measured for 11 planetary nebulae (PNs) in the Virgo Cluster core, at 15 Mpc distance, with the FLAMES spectrograph on the ESO VLT. These PNs are located about halfway between the two giant elliptical galaxies M87 and M86. From the [O III] 5007 Å line profile widths, the

The published version of Table 4 is incorrect; a corrected table (format and values) is given here.

Phoenix spectra of C_2, CN and CO lines will provide oxygen isotopic abundance ratios (^16O/^17O/^18O) and CNO abundances for cool R Coronae Borealis (RCB) stars. The ratios, especially the ^16O/^18O ratio, will be used to test the two leading scenarios for RCB production. These observations were prompted by Clayton et al.'s striking discovery of

Ring-shaped morphologies of nuclear star-forming regions within the central 40{-}200 pc of disk galaxies have been barely resolved so far in three composite Sy 2 nuclei, the Sy 2 Circinus galaxy and in three non-AGN galaxies. Such morphologies resemble those of the standard 1 kpc-size nuclear rings that lie in the inner Lindblad resonance regions

We present the discovery of a companion near the deuterium-burning mass limit located at a very wide distance, at an angular separation of 4.6''+/-0.1'' (projected distance of ~ 670 AU) from UScoCTIO 108, a brown dwarf of the very young Upper Scorpius association. Optical and near-infrared photometry and spectroscopy confirm the cool nature of both