Photon Scattering: Basic Principle of Photon Scattering . Audio Narration is available . No Scattering: Photon Source and Detector . ... For optical photons, scattering goes as wavelength to the -4 power. In the case of blue photons compared to red photons, this means that blue photons are about 10 times more likely to get scattered than red photons. ... Watch the blue photons scatter away from the detector . ... Interstellar dust make stars appear redder than they really are . ...

Program number . ... Infrared Snapshots of 3CR Radio Galaxies . Abstract . ... Holland Ford, The Johns Hopkins University . ... An ACS H-alpha Survey of the Carina Nebula . ... A Snapshot Survey of the most massive clusters of galaxies . ... An ACS Imaging Survey of the Galaxies Hosting Strong Mg II Absorption . ... ACS observations of the galaxies in a giant Ly-alpha nebula at z~2.7 . ... An ACS Survey of a Complete Sample of Luminous Infrared Galaxies in the Local Universe . ... Past weeks: . ...

... J. Brand, M. Felli, R. Cesaroni, C. Codella, G. Comoretto, S. Di Franco, F. Massi, L. Moscadelli, R. Nesti, L. Olmi, F. Palagi, F. Palla, D. Panella, R. Valdettaro . 2007, IAU Symposium 242, p. 223 . ... 2007, ApJ, in press . ... Murphy, G. C., Lery, T., O'Sullivan, S., Spicer, D., Bacciotti, F., Rosen, A. 2007, A , in press . ... Rubini, F., Lorusso, S., Del Zanna, L., Bacciotti, F. 2007, A , in press . ... Coffey, D., Bacciotti, F., Ray, T.P., Eisloeffel, J., Woitas, J. 2007, ApJ, in press . ...

... NGC 3603: X-Rays From A Starburst Cluster . ... Explanation: A mere 20,000 light-years from the Sun lies the NGC 3603 star cluster, a resident of the nearby Carina spiral arm of our Milky Way galaxy . Seen here in this recent false-color x-ray image from the Chandra Observatory, NGC 3603 is well known to astronomers as a young cluster in a large galactic star-forming region. ... Publications with keywords: star cluster - NGC 3603 - star formation . ... Starburst Cluster in NGC 3603 . ...

... Now we present the topographical map for the COOC criterion calculated for both galactic X-ray sources taken from Table  4 and binary pulsar species from Table  6 in coordinates the initial mass ratio exponent - mean kick velocity (Figure  26 ). ... Figure 26: The COOC criterion for X-ray galactic sources and binary radiopulsars versus the initial mass ratio exponent and mean space kick velocity for different kick velocity distributions. ...

... Ultraluminous X-ray sources (ULXs) are located in external galaxies, their X-ray luminosities (10 39 - 10 41 erg/s) are thousand times greater than those of brightest black holes in the Galaxy. ULXs may be supercritical accretion disks around black holes of stellar masses (~10 Solar masses) like that in SS433, or they may be a hypothetical intermediate-mass black holes (hundreds - thousands Solar masses) with standard accretion disks. ... 2) The ULX progenitors were ejected from the star clusters. ...

ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Information & tools for observers . ... Australia Telescope Online Archive (ATOA) . ... ATCA | ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... The Australia Telescope National Facility Colloquium . ...

... Science . ... The goal is to bring together two communitities: the one working on star formation (mostly galactic) and the one working on the formation of young massive clusters (mostly extra-galactic). We will link galactic with extra-galactic work, optical/NIR techniques with sub-mm/mm/radio ones, the formation of stars with the one of massive star clusters - observations and theory. ... Coordinated by Marina Rejkuba (abstract) . ... How did star formation proceed in Globular Clusters? ...

... GSAOI Home . ... Science . ... Deep imaging at J , H , and K is required to identify all stellar objects, brown dwarfs, and planetary mass objects in the central region of the Orion Nebula Cluster down to masses comparable to that of Jupiter. This is required to establish the initial mass function, i.e., the number of stars of each mass that have formed, in this region of intense massive star formation. ... The fields of the GSAOI detectors are shown as four green squares in each frame. ...

... 2001 January 24 . NGC 3603: X-Rays From A Starburst Cluster . ... Explanation: A mere 20,000 light-years from the Sun lies the NGC 3603 star cluster, a resident of the nearby Carina spiral arm of our Milky Way galaxy . Seen here in this recent false-color x-ray image from the Chandra Observatory, NGC 3603 is well known to astronomers as a young cluster in a large galactic star-forming region. ... About APOD | ...

... We found that 10 metal-poor globular clusters are greately distinguished for anomalously small masses on the "destruction rate-mass" plain. As it turned out, these poor clusters, situated 15 kpc farther from the Galactic centre, are somewhat younger than the bulk of the metal-poor globulars, and have anomalously red horizontal branches. ... At the same time, deficiency of distant massive clusters is noticeable with increasing distance from the galactic centre. ...

home education > resources . ... Resources . ... Astronomy Education Bibliography . ... Black Holes: An Introductory Resource List . ... Castelvecchi, D. "A New Breed of Black Hole" in Sky Telescope , Apr. 2006, p. 36. ... Charles, P. Wagner, R. "Black Holes in Binary Stars: Weighing the Evidence" in Sky Telescope , May 1996, p. 38. ... Nadis, S. "The Secret Lives of Black Holes" in Astronomy , Nov. 2007, p. 28. ... Nadis, S. "Black Holes: Seeing the Unseeable" in Astronomy , Apr. 2007, p. 26. ...

... 633Slee+ Fifty-eight fields near rich clusters of galaxies were surveyed with the Very Large Array using scaled arrays in the B/C and/or C/D configurations at 1.5 GHz and 4.9 GHz. The fields were centered on steep spectrum sources in or near clusters that were earlier surveyed with lower resolution telescopes. ... The columns are : . Column 1 Cluster Field (Z1518 = Zw1518.8+0747) . Column 2 distance of source from cluster centre in Abell radii . ... Column 5 1.5 GHz flux (mJy) . ...

... Astrophysics Group . ... AMI Publications . ... AMI Consortium: Hurley-Walker N. et al., 2011, preprint (arXiv:1103.0947) . ... AMI Consortium: Olamaie M. et al., 2010, preprint (arXiv:1012.4996) . ... AMI Consortium: Shimwell T. W. et al., 2010, preprint (arXiv:1012.4441) . ... AMI Consortium: Davies et al., 2010, preprint (arXiv:1012.3659) . ... AMI Consortium: Franzen et al., 2010, preprint (arXiv:1012.3711) . ... AMI Consortium: Rodriguez-Gonzalvez C. et al., 2010, preprint (arXiv:1011.0325) . ...

... Clustering of AGN and QSOs at z=1 . Using galaxies from the DEEP2 Redshift Survey and AGN from the AEGIS/Chandra survey and QSOs from SDSS, I present the cross-correlation function of AGN/QSOs and 'normal' galaxies at z=1. Using the known clustering of DEEP2 galaxies, this leads to an estimate of the bias and typical host dark matter halo mass of AGN/QSOs as a function of X-ray luminosity, which constrains AGN formation models. oral . ... Tuesday: AGN correlation functions, LSS, environments . ...

... This is one of the results from the Arecibo Methanol Maser Galactic Plane Survey that is being presented by graduate student Jagadheep D. Pandian of Cornell University, Ithaca, New York, Dr. Paul F. Goldsmith of Jet Propulsion Laboratory, Pasadena, California and Dr. Avinash A. Deshpande of Raman Research Institute, Bangalore, India to the American Astronomical Society meeting in Washington DC. ... Methanol masers at 6.7 GHz are beacons of massive star formation in our Galaxy. ...

... We show the analysis of low-hard and intermediate states of sources XTE J1550-564, H 1743-322, GX 339-4, XTE J1859-226, XTE J1650-500 and GRS 1915+105. ... Directly applying the scaling technique we also obtain that a ratio of the BH masses in XTE J1859-226 and in XTE J1550-564 is , and the corresponding ratio for XTE J1650-500 and XTE J1550-564 is . These values of scaling factors r implies that BH masses are ; solar masses in XTE J1859-226 and XTE J1650-500 respectively. ...

... Spectrum-RG is joint project of Russian Federal Space Agency (Roscosmos) and German Space Agency (DLR) of X-ray astrophysical observatory. Its main aim is to make all-sky survey in the X-ray (0.5-11 keV) band in order to find all massive clusters of galaxies in the Universe, millions of active galactic nuclei, including obscured ones and hundreds of thousands of Galactic X-ray sources. ... eRosita (Germany) X-ray grazing-incident mirror telescope, consisting of 432 mirrors combined in 7 modules. ...

... The disc accretion process is an essential component of star and planet formation theories. ... Much of the detailed knowledge of the physical processes involved in disc accretion have been gained through observations of nearby ( Z ) of the local environment are thought to affect PMS disc accretion rates, and disc evolutionary timescales. ... I measure the accretion rates of these PMS stars using the intensities of the U /H band excess measured through either optical spectra or imaging. ...

... Tonight's Sky . ... News . ... New type of gamma-ray source found . Astronomers report a new type of energetic gamma-ray emitter is likely related to supersonic winds in stellar clusters. ... T he H.E.S.S. (High Energy Stereoscopic System) collaboration reports the discovery of a new type of energetic gamma-ray source, probably related to supersonic winds from massive stars in a young open stellar cluster. ... Only registered members of Astronomy.com are allowed to comment on this article. ...