... Sun images . ... Sun flares . ... Active areas . September : 2009 . ... No sunspots and sunspot groups can be currently observed on the Sun's surface . The following H-alpha plages without spots can be currently observed on the Sun's surface . ... Coordinates . ... Coordinates and other characteristics of active regions are issued for September 09, 2009 00:31 UT . Last updated: September 10, 2009 00:00 UT . ... 7(499)132-65-96, Fax: +7(499)132-65-97 . ...

... ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . ... Parkes | ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... The Active Algol Binary KZ Pavonis . ... The Algol type eclipsing binary KZ Pav has been observed over one complete orbit (0.95 days) with the Australia Telescope Compact Array. ...

Astronomy Picture of the Day . Centaurus A: X Rays from an Active Galaxy . ... CXO , NASA Explanation: Its core hidden from optical view by a thick lane of dust, the giant elliptical galaxy Centaurus A was among the first objects observed by the orbiting Chandra X-ray Observatory . ... Publications with keywords: active galaxy - X-ray - NGC 5128 - Centaurus A . Publications with words: active galaxy - X-ray - NGC 5128 - Centaurus A . ... X Ray Stars of Orion . ... Jumbled Galaxy Centaurus A . ...

. Page created and maintained by E. Landi. Mail comments regarding interface to enricol@arcetri.astro.it Mail comments regarding spectrum data to mlandini@arcetri.astro.it, enricol@arcetri.astro.it

... 2001 August 16 . Centaurus A: X-Rays from an Active Galaxy . ... CXO , NASA . ... Astronomers were not disappointed, as Centaurus A's appearance in x-rays makes its classification as an active galaxy easy to appreciate. ... Blasting toward the upper left corner of the picture, the jet seems to arise from the galaxy's bright central x-ray source -- suspected of harboring a black hole with a million or so times the mass of the Sun. ... About APOD | ... NASA Technical Rep.: ...

We present Spitzer 3.6-160 О?m images, Spitzer mid-infrared spectra, and JCMT SCUBA 850 О?m images of the Sombrero Galaxy (NGC 4594), an Sa galaxy with a 109 Msolar low-luminosity active galactic nucleus (AGN). The brightest infrared sources in the galaxy are the nucleus and the dust ring. ...

. Home . News . Gallery . Events . Twitter . Press Releases . Links . Contact Us . Calendar . Press & Web Coverage . Previous . Next . List . Deirdre Kelleghan kept observing the Sun and she sent us a new wonderful drawing: "Active Region 10999, June 20th 2008 13:45 UT; PST 40/8mmTVP eyepiece/50X upscaled by eye; soft pastels and graphite on black paper". Thank you, Deirdre! . Tuesday, 24 June 2008 01:52 . International Year of Astronomy, Ireland National Node . [Back To Top] .

... Science . ... Science Users Information > Science Publications > Science Announcements > Clustering Measurements of Active Galactic Nuclei . ... Observing Facilities . ... ESO Data . ... Galaxies and active galactic nuclei (AGN) are not randomly distributed in the Universe. ... This ESO workshop, which will be the first ever dedicated workshop on AGN clustering, aims to summarise our current understanding of AGN clustering and how the community should prepare for upcoming data sets and challenges. ...

... Tonight's Sky . ... The Magazine . ... Observing . ... Magazine . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Open cluster NGC 2818, spiral galaxy NGC 2964, and spiral galaxy NGC 2976 . ... Astronomy for Kids . ... active galactic nuclei . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ... Astronomy Magazine . ...

... RATAN-600 data for the BL Lacertae objects (multi-frequency catalogue, Version 1.0) . GPS radio sources . ... BL Lacertae objects . ... The difference between these objects is the peak frequency of the synchrotron component of their spectral energy distribution (HBLs: high-energy peak, LBLs: low-energy peak, IBLs: intermediate). ... The observations were carried out with the RATAN-600 radio telescope during 2006-2011 at six frequencies: 1.1, 2.3, 4.8, 7.7, 11.2 and 21.7 GHz. ...

... Mindful of these biases, I can now explore the relations between the measured rotation periods and various other observables. The hypothesis behind monitoring stellar variability is that active stars have asymmetric spot distributions on their photospheres. ... They found that only stars with rotation periods greater than seven days show variations greater than 0.4 magnitudes at I. Bouvier et al . ... 1993a) demonstrated a relation between X--ray flux and spectral type in ZAMS stars. ...