... We have studied scaling relations (virial mass versus CO luminosity, luminosity versus size, linewidth versus size) for molecular clouds in the 30 Dor and N 159 regions in the Large Magellanic Cloud. ... The study of molecular clouds in the Galaxy has resulted in a number of scaling relations between global cloud properties such as mass, density, luminosity, size and velocity dispersion (e.g. Larson (1981) , Scoville & Sanders (1987) , Solomon et al. ... Elmegreen B.G., 1989, ApJ , 338 , 178. ...

... Scaling relations of galaxies: . ... 2007) . ... This research is now being extended to other clusters such as Hydra and Centaurus, by Ingo Misgeld . ... 2007 , Misgeld et al. 2008 and 2009 ) support a picture where the scaling relations of dwarf galaxies are shaped more by internal than external agents, given that colour-magnitude and magnitude-surface brightness relations agree quite well between the low-density Local Group environment and dense clusters like Fornax and Hydra. Misgeld et al. ...

. Go Here for Hubble Ultra Deep Field . ___________________________________________________________________ The Electronic Universe Project e-mail: nuts@moo.uoregon.edu

... Most of the spirals discussed in the following are well-known starburst galaxies (M 82, NGC 253, etc.) In addition to their nuclear activity, which makes them so popular, the selected galaxies have several other phenomena in common, such as bars, gas outflow, and possibly nuclear rings. ... I will show that the gas dynamics in the outer and inner parts of these galaxies are strongly related to their starburst activity. ... NGC 253 . ... The peculiar galaxy NGC 4258: A black hole candidate. ...

We compare atomic gas, molecular gas, and the recent star formation rate (SFR) inferred from HЮБ in the Small Magellanic Cloud (SMC). ... This allows us to disentangle conversion factor effects from the impact of metallicity on the formation and star formation efficiency of molecular gas. ... At a fixed total gas surface density the SMC has a 5-10 times lower molecular gas fraction (and star formation rate) than large spiral galaxies. ...

... A universal physical relation for quasars . ... Harvey Tananbaum and his collaborators have first observed a relation between the soft X-ray and the optical/ultraviolet emission in AGN in 1979. Such relation is nonlinear, and it is usually parameterized as dependence between the logarithm of the monochromatic luminosities at 2500 †Е ( L 2500†Е ) and 2 keV ( L 2keV ) . ... Yet, the dispersion along the L 2500†Е тАУ L 2keV relationship is found to be rather high, typically ~0.35тАУ0.4 in log units. ...

PEGASE: Project de'Etude des Galaxies par Synthese Evolutive (by Damien Le Borgne and Brigitte Rocca-Volmerange) . Galaxy colours (by Robin Stevens) . ... Images of radio galaxies and quasars mapped at VLA . Atlas of radio galaxies in 3CRR sample (images, description, classification, etc.) Radio Galaxy and Quasar Images at Other Sites by A.Bridle . ... Radio galaxies in Abell clusters . ... Digitized Sky Survey images . Faint Images of Radio Survey at Twenty-cm at VLA . ...

A comparative study of type I and type II supernovae . ... Sternberg State Astronomical Institute, Moscow, U.S.S.R. (Received 26 November, 1985) . ... No significant difference between SNe I and SNe II has been found in their radial distribution and frequency of outbursts in spiral galaxies. ... The radial distribution of type Ia SNe in spiral galaxies is only slightly steeper than the one for SNe II, while SNe Ib/c are more concentrated towards the central regions. ...

... Discovery of 47-s pulsations in the X-ray source 1RXS J225352.8+624354 / arXiv:1305.3439 , May 2013 . ... Optical spectroscopy of X-ray source IGR J22534+6243 / Atel # 4248 . ... Search for counterparts of newly discovered INTEGRAL/IBIS sources / Atel # 4166 . New INTEGRAL Galactic Plane Survey in SkyView / blog . Likely X-ray counterparts of newly discovered INTEGRAL/IBIS sources / Atel # 4165 . AGN in the INTEGRAL/IBIS 9-year Galactic hard X-ray survey / Atel # 4151 . ...

... 025.04) Correlating Arecibo Radar and IRTF Near-Infrared Spectral Observations of 105 Artemis . 029.14) Fast-Drifting Radio Bursts Seen on the Flare Star AD Leo with the Arecibo Observatory . ... 095.01) The Arecibo Legacy Fast ALFA Survey: HI Sources in the Northern Virgo Cluster Region . 095.02) The Arecibo Legacy Fast ALFA HI Survey: The Rich Galaxy Group Zwicky 1400+0949 . ... 104.02) Radio Emission Signatures of the Crab Pulsar's High Frequency Interpulse . ...

... CV & PUBLICATIONS | ... Nicholls, DC, Dopita, MA, Sutherland, RS, Jerjen, H, & Kewley, LJ " Metal-poor Dwarf Galaxies in the SIGRID Galaxy Sample. ... Nicholls DC, Jerjen, H, Dopita MA, & Basurah, H. (2014) " Nebular Metallicities in Two Isolated Local Void Dwarf Galaxies ", Astrophysical Journal 780, 88 * . ... Sweet SM, Drinkwater MJ, Meurer G, Bekki K, Dopita MA, Kilborn V, & Nicholls DC, " CHOIRS H I Galaxy Groups: The Metallicity of Dwarf Galaxies" , (2014) Astrophysical Journal , 782, 35 * . ...

... 2013: . Evidence for the connection between turbulent gas motions and star formation in dwarf galaxies . ... Moiseev A.V. "Ionized gas rotation curves in nearby dwarf galaxies", Astrophysical Bulletin, 2014, Volume 69, Issue 1 . Moiseev A.V., Tikhonov A.V., Klypin A.A. "What controls the ionized gas turbulent motions in dwarf galaxies", submitted to MNRAS . ... Determination of the mass of a supermassive black hole in AGN Mkn6 based on spectro-polarimetric observations . ... Archive . ...

Links on this page are to sites that hold information on the Sun , our nearest star . ... Big Bear Solar Observatory (BBSO) , California, USA. Mauna Loa Solar Observatory (MLSO) , Hawai'i, USA. ... Space Environment Center, Current Solar Images , Boulder, Colorado, USA. ... Solar Data Analysis Center, Latest Images , at GSFC, Maryland. ... NSSDC - National Space Science Data Center, Solar Physics (at GSFC). ... NSSDC - National Space Science Data Center, Space Physics (at GSFC). Back to Links ...

. Next: Introduction Up: ROSAT HRI Recipes Previous: Summary of tasks in . љ . Introduction . Data analysis and Spatial Corrections . A Preliminary Investigation . Dewobble Procedure: treating each obi separately . Additional Tools . An Example - 3C 120 . References . rsdc@cfa.harvard.edu . 1998-06-10

Next: Estimating the angle Up: Wavelength Calibration Previous: General Description . The wavelength calibration involves a physical equation, the echelle relation and regression analysis to achieve estimates of the dispersion relation. Provided that the echelle dispersion is performed with a grating, any echelle spectrum can be calibrated usually with four lines used as pre-identifications and a catalog of laboratory wavelengths associated to the calibration lamp. ... Echelle Relation) . ...

... The concepts of Fourier frequency and wavelet duration are obviously related. ... Among many sensible definitions, we chose to require that the peak of the wavelet mean spectrum should be matched with the singularity of the Fourier transform of the cosine wave. Then, it can be shown that the frequency of the cosine is related to the wavelet duration by the relation . ... The ambiguous definition of the duration of an event is common to the sizing of any object of irregular shape. ...

... All the information about the propagation of a given plasma wave mode is contained in the appropriate dispersion relation, which relates the angular frequency w to the wave number k (magnitude of the propagation vector k ). ... Phase velocity . ... Group velocity . ... Wave propagation can also be described using diagrams called phase velocity or wave normal surfaces , which give the variations of the magnitude of the phase velocity of plane waves with respect to the magnetic field direction: . ...

... SUN MOON MERCURY VENUS MARS, JUPITER SATURN . ... Mars . ... Previously understood that magnetic fields were directly related to rotation, so when I read that Mars, like Venus, didn't have one, my understanding crumbled. What exactly causes magnetic fields in planets? ... RELATED TOPICS: MAGNETIC FIELD . Planetary magnetic fields are definitely related to rotation, but directly not so much. ... Get instant access to subscriber content on Astronomy.com! ...

... The task also issues a number of housekeeping related messages and values and also writes several keywords to the EXPOSURE extension (the information is usually CCD-dependent and it is thus important that it is kept and propagated through the event file processing chain). ... Filter: the filter wheel position is derived from the position sensor potentiometer (housekeeping column F1122 contained in the main periodic housekeeping file PNPMH1 , HK mnemonic H_CE_FWSPOT). ...

... Bad Astronomy . ... Bitesize Astronomy . ... Last week's Snack talked about how black holes can affect the environment around them in such a way as to be very bright . ... It's a common misconception that black holes always have matter swirling into them. ... As this matter gets closer and closer to the black hole it piles up and a large, fairly flat disk forms. This is called the accretion disk , because matter from this disk accretes (that is, falls in) on the black hole. ... 2008 Phil Plait. ...