... 2002 June 20 . Bright Galaxy M81 . ... Explanation: Big and beautiful spiral galaxy M81 , in the northern constellation Ursa Major , is one of the brightest galaxies visible in the skies of planet Earth. This superbly detailed view reveals its bright nucleus, grand spiral arms and sweeping cosmic dust lanes with a scale comparable to the Milky Way . ... The errant dust lane may be the lingering result of a close encounter between M81 and its smaller companion galaxy, M82 . ... About APOD | ...

... December 13, 1997 . The Coma Cluster of Galaxies . ... The Coma Cluster of Galaxies pictured is one of the densest clusters known - it contains thousands of galaxies . Each of these galaxies house billions of stars - just as our own Milky Way Galaxy does. ... In fact, the Coma Cluster is so big it takes light millions of years just to go from one side to the other! Most galaxies in Coma and other clusters are ellipticals , while most galaxies outside of clusters are spirals . ...

Supernova 1999cl in M88 . This page is devoted to information on Supernova 1999cl in M88 Basic information on this SN, including the last reported brightness, on this Supernova can be found on the main supernova page. Information on the original web pages for many of these images can be found on the Supernova links web page. ... M1 Supernova Search has a 1999cl page . ... Pedro Re' Animated gif image . ... DAX Observatory . ... vsnet-obs 21040 ] (fwd) Observation of Supernova 1999cl in M88 . ...

... Scientific Topics · · · · · · · · · · · · Historical surveys : spectral and colorimetric surveys for AGN , surveys for UV-excess galaxies AGN fro m IR/submm surveys : 2MASS, IRAS, ISO, AKARI, SCUBA, SST, WISE, Herschel AGN fro m radio/ mm surveys : NVSS, FIRST, ALMA, Planck, and others AGN fro m X-ray/gamma-ray surveys : ROSAT, ASCA, BeppoSAX, Chandra, XMM, INTEGRAL, Fermi, HESS, MAGIC, VERITAS Mult iwavelength AGN ... The deadline for early online registration is April 30, 2013. ...

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 . ...

... 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. ...