Deep Space Image Index . ... Cartwheel Galaxy ( GIF , 299K; JPEG , 62K; caption ) . NGC1850 - Tale of Two Clusters ( GIF , 255K; JPEG , 117K; caption ) . Cat's Eye Nebula ( GIF , 113K; TIF , 1M; caption ) . Ring Structure Around Supernova 1987A ( TIF , 2M; caption ) . 30 Doradus Nebula ( GIF , 379K; caption ) . Eta Carinae Star ( GIF , 433K; caption ) . Cygnus Loop Supernova Blast Wave ( TIF , 4M; caption ) . Spiral Galaxy M51 ( TIF , 769K; caption ) . ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Risks Comparable to NEOs . ... The Increasing Rate of Discovery of Asteroids . ... Comet and Asteroid Collision Probabilities . ... Extreme albedo comets and the impact hazard (PDF Format) . ... Asteroid Impact Animations . ... Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids - 2002 . ... The Spaceguard Survey Report, 1992 (PDF) . Tsunami from Asteroid/Comet Impacts . ...

M1 image More About M1 Nice Color Picture . ... M16 image More About M16 HST image . ... M31 image More About M31 Nice Color Picture . ... M42 image ; M43 image More About M42/43 Nice Color CCD Picture . M51 image More About M51 Color Image of M51 M51 Supernova . M57 image More About M57 Nice Color CCD Picture Very Deep M57 Image . ... M81 image More About M81 M81 Supernova Ultraviolet Image of M81 More about Ultraviolet Imaging . M82 image More About M82 M82 False Color M82 True Color . ...

... Initially SAI Supernova Catalogue was presented in the form of filebased system. ... The current version of SAI Supernova Catalogue presents data on supernovae together with data on their parent galaxies. ... The main source of data for the galaxies was LEDA database. ... In some cases our data were compared with the ones from the Asiago Supernova Catalogue and from List of Supernovae at Harvard-Smithsonian Center for Astrophysics, but the compilation of our Catalogue is carried out independently. ...

... Structure of Data . ... Catalog . ... In SAI OCL Catalog, we introduce our work on investigation of the Milky Way system of open star clusters. The main goal of our study is a search for new clusters using huge surveys. 168 new clusters have been already discovered by us using J,H,Ks data from 2MASS point source catalog. ... For 141 new clusters, we found their physical parameters using J,H,Ks data from 2MASS catalog and, for a number of clusters, our UBVRI CCD observational magnitudes. ...

... Next: Unsupervised Catalog Classification Up: Object Detection and Previous: Classification of Objects . ... Multi-resolution allows for image analysis in terms of different scales. ... This approach is used for the detection (and subsequent analysis) of globular cluster systems around elliptical galaxies, and for image characterization and object trawling in large image databases. ... The applicability of this approach to object detection in large image collections has been investigated. ...

... Tonight's Sky . ... Observing . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... The 109 objects in a March globular cluster marathon . ... In the March 2014 issue of Astronomy, I challenged readers with the question, How many globular clusters can you see in might night? Taking the Messier marathon as inspiration, I made a list of 109 globular clusters to track down in a single night in March. ... Get instant access to subscriber content on Astronomy.com! ...

... M15: A Great Globular Cluster . ... Credit: The Electronic Universe Project Explanation: A globular cluster is a system of about one million stars that together orbit a galaxy. One of the brightest globular clusters in our Milky Way galaxy is the pictured M15, the fifteenth object on Messier's list of diffuse objects on our sky. ... Publications with keywords: M15 - globular cluster . Publications with words: M15 - globular cluster . ... M13: The Great Globular Cluster in Hercules . ...

... The routines implemented are CLUSTER which has 8 options for hierarchical clustering and PARTITION which carries out non--hierarchical clustering. ... The former is non--hierarchical clustering or partitioning. The latter is hierarchical clustering. Brief consideration will show that a sequence of n-1 agglomerations are needed to successively merge the two closest objects and/or clusters at each stage, so that we have a set of n (singleton) clusters, n-1 clusters, ..., 2 clusters, 1 cluster. ...

... Indeed, one alteration of orbits can be the outright ejection of a planet. When several big planets are orbiting a star under each other's influence, the system is inherently unstable. ... We know of no good reason why the smallest objects with fusion should have the same mass as the smallest objects that can form by themselves. ... 6) Mission Definition . ... I don't think this mission is impossible, and will suggest a definition in a future article in Mercury. ... Good luck! . ...

IFP gallery SCORPIO (since 2000). Here some data observed on the 6m telescope with IFP installed in the SCORPIO focal reducer are presented. ... Velocity field . Mkn 1157 was observed 1 Sep. 2002 in the Ha emission line. Texp =32x240 sec, seeing 1.5", IFP260. ... This galaxy was observed September, 23 2000 in the Ha emission line, Texp=32x120 sec, seeing 2.5", IFP260. ... PV Cep was observed at the 6m telescope in May, 25 2003 in the [SII] 6716A with IFP501, Texp=36x200 sec, seeing 1.0". ...

... Radiation mechanisms of astrophysical objects: classics today . ... S.A. Balashev, D.A. Varshalovich, A.V. Ivanchik, V.V. Klimenko , Ioffe Institute, Russian Federation . ... D.P. Barsukov, A.I. Tsygan , Ioffe Institute, Russian Federation . ... A.I. Kopylov, F.G. Kopylova , Special Astrophysical Observatory (SAO RAS), Russian Federation . ... F.G. Kopylova, A.I. Kopylov , Special Astrophysical Observatory (SAO RAS)