----------------------------------- Cristian Monea 22 Apr 2009 21:10 Catalog de obiecte ceresti ----------------------------------- Un catalog structurat de obiecte cerești. Este ușor de citit și bine structurat: "BY RA - All objects, sorted by increasing right ascension, to assist the user in indentifying those objects that are "up" and available for observation on any given night. BY TYPE - A cross-reference of the same set of objects, but grouped by object type: Ephemeris Stars - moderately bright stars near +40° declination, useful for stellar initialization. Bright Stars - Alternate stellar initialization objects in the event that an appropriate Ephemeris Star cannot be found. Also useful to demonstrate how a bright star appears telescopically. Red and Double Stars - Interesting, and sometimes challenging, examples of single, binary, and multiple star systems, sometimes with striking color combinations. Open Clusters - Also known as "galactic clusters", the product of relatively recent starbirth regions. Tend to be loosely organized and dominated by blue stars. Globular Clusters - Ancient, tightly-bound star systems which tend to group around the nucleus of the Milky Way. Contain thousands of component stars. Planetary Nebulae - The "puffed-off" outer shells of a dying, Sun-like star. Named by Hershel, for their (sometimes) telescopic resemblance to Uranus, which he discovered. Diffuse Nebula - Glowing gas clouds, primarily due to hydrogen-alpha emission. Starbirth occurs in these regions, ultimately resulting in a new open cluster. Cataclysmic - Exotic, explosive, highly-energetic sources. Galaxies - "Island universes" of stars lying outside our own Milky Way Galaxy. MESSIER - A separate listing of this venerable and historical catalog. M&M - A separate listing of Mullaney and McCall's catalog of celestial showpieces." Și īn plus, catalogul Herschel și Messier (īn format Excel).