... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. August 17, 1999 . A Crescent Sunrise . ... Explanation: Normally, the Moon shows phases, but the Sun does not. ... When the Moon is closer to the Sun than the Earth, only part of it appears to be lit - resulting in a familiar crescent-shaped phase . ... Nothing was wrong with Sun - viewers were witnessing the end of a solar eclipse . ...

Computer-readable version of General Catalogue of Variable Stars, Vol.V. Extragalactic Variable Stars. ... It contains the first Catalogue of variable stars in external galaxies as well as a Catalogue of extragalactic supernovae. ... Note that NGC 1466 is a globular cluster (not a galaxy) between the LMC and the SMC; we presented it separately, because it is not clear to which galaxy to attribute its variable stars. Note on VarNo: variable star No within the galaxy. ...

... The distance scales of the objects are matched both by comparing the first derivatives of the angular velocity determined separately from radial velocities and proper motions and by the statistical-parallax method. ... Good agreement between the inferred 0 and our calculations based on space velocities suggests that the Lindblad relation holds throughout the entire sample volume. ... Brandt and Blitz (1993) published the distances and radial velocities for a total of 206 H II-regions. ... Astron. ...