... 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 . ...

Next: Identifications and Efficiency Up: THE DEEP X-RAY RADIO Previous: Source Classification . ... For some sources which did not have NVSS positions before the time of optical observations, arcsecond positions from the Texas survey (Douglas et al. 1996) and NED (typically based on VLA data) were used. ... All X-ray/radio sources without counterparts on the survey plates were imaged at either the KPNO 0.9m or the CTIO 0.9m telescopes. ... Previously Identified Sources . Sample Properties . ...

... A radio galaxy is a galaxy that emits an unusually big amount of energy at radio wavelengths. ... Inside of each galaxy with an active nucleus (radio galaxies are among them) there must be a system of a "central machine" responsible for the colossal amount of the emitted energy from radio to gamma ranges. ... Sometimes a radio source in an active galaxy may flare again if the needed conditions appear (a new portion of matter would fall into the furnace of the "central machine"). ...

... The search for distant objects which can be both galaxies and quasars is one of the most important problems of observational astrphysics, because it allows one to determine cosmological parameters connected with the time of appearence and evolution of stellar systems, large scale structure of the Universe. ... Radio galaxies are important objects to be studied because they are sources of infrared-optical-ultraviolet continuum, emission lines and continual radio emission. ...

... Posts tagged ?afterglow? ... Without an optical afterglow, a galaxy within the 2 arc second error region of a GRB x-ray afterglow is identified as a host galaxy; however confusion can rise due to the facts that 1. the edge of a galaxy is diffused, 2. multiple sources could exist within 2 arc second error region, 3.the distance between the galaxy and the x-ray afterglow is measured by projection, and 4. lensing causes increase of brightness and position shifts. ... ArXiv] GRB host galaxies, Aug. ...

... Up: Data Analysis and Processing Techniques . ... Also, a method for quality control of CCD observations is suggested. ... Everyone who observes a celestial object using a CCD detects moving celestial objects as a ``by product''. ... We hope that our investigations may be useful for near-Earth space control and also for searches of the moving celestial objects through analysis of old and new CCD frames obtained at any amateur or professional astronomical observatory. ...

ESO PR Photo 18b/00 . ... Caption : Images of two of the novae in NGC 1316 that were discovered during the observational programme described in this Press Release. ... In particular, no less than four novae were detected in a single giant galaxy within only 11 days . ... Moreover, the discovery of four novae in one galaxy in the Fornax cluster was possible with only 3 hours of observing time per filter. ... ESO Press Information is available on the WWW at . http://www.eso.org/outreach/press-rel/ . ...

... Our Galaxy . ... Space Flight . ... No Comments Dim and isolated, the dwarf irregular galaxy WolfтАУLundmarkтАУMelotte (WLM) could be described as an astronomical тАЬliving fossilтАЭ as it seems to have developed since it formed billions of years ago [ ] . Continue Reading.. ... Posted on November 24, 2011 | ... 3 Comments The astronomy community is excited by the discovery of an exploding star, a supernova, in a galaxy 21 million light years away in the constellation Ursa Major. ...

... Neutral hydrogen is the best tracer of accreting and outflowing gas, however very hard to detect due to its low column density. ... Simulations predict that in order to detect HI in the extended environment of galaxies, brightness sensitivities well below NHI ~1018 cm-2 are required (e.g. Popping et al. ... Direct aims of the projects include: - Achieve a 1 sigma NHI of 2.5x1017 cm-2 over 20 km/s. - Measure the extended gas content of galaxies to detect gas accretion and outflows. ...

... Courtesy of NASA/ESA Observation data (J2000 epoch) Constellation Right ascension Declination Redshift Distance Type Serpens Caput 15h 17m 14.4s[] +21° 35 08[] 12,740±50 km/s[][1] 600±30 Mly (183±8 Mpc)[1] SA0(r) [citation needed ] [a] Apparent dimensions (V) 0.28 в 0.28[] Apparent magnitude (V) 16.0[] Notable features Ring galaxy Other designations PGC 54559,[] PRC D-51[] See also: Galaxy, List of galaxies Hoag's Object is a non-typical galaxy of the type known as a ring galaxy. ...

... Hoags Object: A Strange Ring Galaxy . ... Credit Copyright: R. Lucas ( STScI / AURA ), Hubble Heritage Team , NASA Explanation: Is this one galaxy or two? ... How Hoag's Object formed remains unknown, although similar objects have now been identified and collectively labeled as a form of ring galaxy . ... The above photo taken by the Hubble Space Telescope in July 2001 revealed unprecedented details of Hoag's Object. ... July . ... July 2013 . ... The Double Ring Galaxies of Arp 147 from Hubble . ...

General Forum Message . Forums: . ... Deep Space Object Galaxy Near M13 . ... Can anyone tell me if there is a DSO (likely a galaxy) near M13? ... The reason it interests me is that I drew a sketch of M13 years and years ago while observing - and that object is one of the handful of 'stars' that I drew. ... www.astronomy.net . About Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... arXiv.org . astro-ph . ... We fit the near-infrared to radio spectral energy distributions of 30 luminous and ultra-luminous infrared galaxies with pure starburst models or models that include both starburst and AGN components to determine important physical parameters for this population of objects. In particular we constrain the optical depth towards the luminosity source, the star formation rate, the star formation efficiency and the AGN fraction. ...

... Observing . ... Observing springtime deep-sky objects with a large telescope . Springtime observing for small telescopes . ... Astronomy magazine Editor David J. Eicher shares 10 of his favorite springtime deep-sky objects, including the NGC 3190 galaxy group, 3C 273, and NGC 3242. ... In this video, Astronomy magazine Editor David J. Eicher discusses deep-sky objects in the spring sky you can see with a 12-inch or larger telescope. ... Get instant access to subscriber content on Astronomy.com! ...

User catalogs allow you enter positions for your objects into a file, to save time during an observing run. ... Before diving into the details, here is an example: # default coordinate system and object # (these are the standard defaults, so if you like them you can omit this line) CSys=FK5; Date =2000; RotType= Object ; RotAng=0 # some random objects # Name Pos1 (e.g. RA) Pos2 (e.g. Dec) Options in keyword-value format NGC6543 rot 90 ... Object Data . Defaults . Catalog Options . ...

... About ATMoB . ... The Observing Committee is starting an Observing Awards Program to promote observing among the membership of the Amateur Telescope Makers of Boston. ... Participant must be a current member of the Amateur Telescope Makers of Boston . ... To qualify for your Observing Award Certificate, turn in your worksheet and drawings to an ATMoB Observing Committee member or observing@atmob.org . ... This Excel sheet has useful macros. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

... In one situation, we can use light from quasars to probe the material between us and them because that light may pass through one or more galaxies or gas clouds on its way to us. The gas inside the galaxies or the intergalactic clouds acts then as a filter, absorbing selected wavelengths from the quasar light. ... Light from a quasar must pass through clouds of gas and even faint galaxies -- each leaving its imprint on the light -- before we receive it here on Earth. ... Gravitational lensing . ...

... We suggest simple method of the selection of distant galaxies based on their radio properties. ... RC0015+0503a , RC0015+0503b , RC0015+0501 , RC0034+0513 , RC0038+0449 , RC0042+0504 . ... RC0105+0501 , RC0110+0500 , RC0117+0503 , RC0126+0502 , RC0133+0459 , RC0135+0450 , RC0137+0539 , RC0143+0505 , RC0152+0453 , RC0154+0459 , RC0159+0448 . ... RC0209+0501b , RC0213+0516 , RC0226+0512 , RC0250+0512 . ... RC0302+0456 , RC0308+0454 , RC0311+0507 , RC0318+0456 , RC0355+0449 . ...

... Cross-shaped galaxy ZGC 2315+03 (Fig.1) has been described by Zwicky (1971) as ``post-eruptive or the result of the crossing of a compact galaxy through an edge-on spiral'' . This object was included in the Polar-Ring Catalog (C-71) by Whitmore et al. (1990) as a possible candidate for Polar-Ring Galaxies (PRG). ... One of them is galaxy 'disk' and the other is 'polar-ring'. ... The facts against the polar-ring nature of ZGC 2315+03 can be summarized as follows: . ...

... Classes . ... Nebula Class Reference . ... getInfoString (const StelCore *core, const InfoStringGroup &flags) const . ... getCloseViewFov (const StelCore *core=NULL) const . ... getVMagnitude (const StelCore *core, bool withExtinction=false) const . ... getSelectPriority (const StelCore *core) const . ... getEquinoxEquatorialPos (const StelCore *core) const . ... getJ2000GalacticPos (const StelCore *core) const . ... getPositionInfoString (const StelCore *core, const InfoStringGroup &flags) const . ...