... 2008 November 29 . Chilean Skyscape . ... Explanation: Night skies over Chilean mountain top observatories can be dark and clear, with glorious cosmic vistas . In this recent example, the plane of our Milky Way galaxy stretches parallel to the horizon , the galactic center's star clusters, dark dust clouds, and glowing nebulae hovering in the west. ... A close pairing through this weekend, by Monday, December 1 , they will be joined by the young crescent Moon . ... About APOD | ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. November 11, 1997 . The Annotated Galactic Center . ... Constellations of nearby stars include Sagittarius , Libra , Scorpius , Scutum , and Ophiuchus . ... Open clusters include M6 , M7 , M18 , M21 , M23 , M24 , M25 . Globular clusters include M9 , M22 , M28 , M54 , M69 , M70 . ... About APOD > . ... NASA Technical Rep.: ...

ABSOLUTE PROPER MOTIONS OF 331 OPEN CLUSTERS . ... The proper motions of stars in the fields of 331 open clusters were taken from Four-Million Star Catalog (4M-catalog) of positions and proper motions (Volchkov et al. ... The absolute proper motions for 21 young open clusters have been derived by comparison of precise relative proper motions of individual stars and their corresponding absolute proper motions. ... Sign of proper motions in RA . ... 0.0001 arcsec/yr . ... rms error in RA proper motion . ...

... At present, he is a Leading researcher at the Department of Non-Stationary Stars and Stellar Spectroscopy, heading the group of the General Catalogue of Variable Stars, and a Leading researcher at the Department of Variable Stars and Galactic Astronomy of the Sternberg Astronomical Institute, heading the group of Variable Stars. ... P.P. Parenago, B.V. Kukarkin, P.N. Kholopov leaded the team of variable star catalogue compilers at Astronomical Council/INASAN and at Sternberg Institute through years....

... Here is a brief outline of the current theory of the events in the early history of the solar system: . A cloud of interstellar gas and/or dust (the "solar nebula") is disturbed and collapses under its own gravity. ... The gas cools off enough for the metal, rock and (far enough from the forming star) ice to condense out into tiny particles. (i.e. some of the gas turns back into dust). ... Once the larger of these particles get big enough to have a nontrivial gravity, their growth accelerates. ...