The development of adaptive optics systems for projects related to large telescopes demands a proper knowledge of the atmospheric turbulence. Due to the lack of long-term information on optical turbulence, high-altitude winds (in particular winds at the 200-mbar pressure level) were adopted as a parameter for estimating the total turbulence at a

We correct the estimates of the dispersions in the rotational velocities for early-type stars in our Galaxy (Dufton et al. 2006, A&A, 457, 265) and the Magellanic Clouds (Hunter et al. 2008, A&A, 479, 541). The corrected values are π1/4 (i.e. approximately 33%) larger than those published in the original papers.

The observations we reported in ATel #2166 were actually of nova M31 2009-08b, not 2009-08d. Therefore, ATel #2166 confirms the nova nature of nova M31 2009-08b, located 965" east and 1962" north of the center of M31. See http://www.cfa.harvard.edu/iau/CBAT_M31.html#2009-08b

We have confirmed the detection of a surprising, and so far unique, absorption feature on a main-belt asteroid, 24 Themis. Our 2 to 4 micron reflectance spectra were obtained over 7 hours (84% of Themis’ rotational period) on January 23, 2008 UT, from NASA's Infrared Telescope Facility. All our spectra confirm the shape and depth of the 3.1 micron

Context: The structure and dynamics of small vertical photospheric magnetic flux concentrations has been often treated in the framework of an approximation based upon a low-order truncation of the Taylor expansions of all quantities in the horizontal direction, together with the assumption of instantaneous total pressure balance at the boundary to

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