... The concerns here are similar to those for observing bright targets; saturation and blooming of the bright companion PSF must not impact the faint target. Also, one may need to consider subtracting the PSF of the bright object, and effects which limit the accuracy of that subtraction. If the bright companion will saturate and bloom, it will be necessary to rotate the CCD so that blooming along the CCD columns does not obliterate the faint target. ...

... According to the most popular cosmological paradigm, the greater part of the galaxy mass is accumulated in the dark matter halo. ... The polar ring galaxies (PRGs) reveal external rings or disks of gas, dust and stars rotating in a plane roughly perpendicular to the disk of the central galaxy. ... The shape of the dark halo in the model was chosen so as to achieve the best fit to the observed rotation of both galaxies themselves and their polar rings. ... The SPRC-7 galaxy. ...

True Color Image Gallery: Galactic SNR | Magellanic Cloud SNR . ... Distance: 50kpc(distance to LMC, Westerlund(1990) ) . ... Radio Images Page . ... Exposure uf . ... Exposure uf Exposure time of unfiltered event file . Exposure f Exposure time of filtered event file . ... Event 2 FITS File . ... AUX file . ... N H = 0.5(10 22 cm -2 ) Assumed distance: 50kpc (distance to LMC, Westerlund(1990) ) . see fit detail page for more about the fit. see chandra spectrum page for region used. ...

... Science Users Information > Observing with ESO Telescopes > Phase 2 Preparation > Observing conditions . ... Service Mode Philosophy . ... The following definitions of the observing conditions are common between Phase 1 preparation and Phase 2 preparation, as well as between Service Mode and Visitor Mode observations. ... There are additional Service Mode Policies and Service Mode Guidelines regarding the observing conditions. ... Seeing (Phase 1) and Image quality (Phase2) constraints . ... Moon . ...

CHIANTI - an atomic database for emission lines. ... K.P.Dere, E.Landi, H.E.Mason, B.C.Monsignori-Fossi, P.R.Young, 1997, A , 125, 149 . Article: Available from ADS . The Arcetri Spectral Code for thin plasmas . E.Landi M.Landini 1998, A , 133, 1 . ... E.Landi, M.Landini K.P.Dere, P.R.Young, H.E.Mason, 1999, A , 135, 339 . ... K.P.Dere, E.Landi, P.R.Young, G.Del Zanna, 2001, ApJS, 134, 331 . ... G.Del Zanna, B.J.I.Bromage, E.Landi, M.Landini, 2001, A , 379, 708 . ...

... Usually, H I is seen as bright emission against a darker background, but under the right viewing conditions, it can also be seen as dark absorption against a brighter background. In the case where the background is itself H I emission, the hydrogen is said to be self-absorbed, and the radiative transfer process is termed H I self-absorption (HISA). ... Shown below is a single CGPS H I 21cm spectral line channel at a radial velocity of -41 km/s in the Local Standard of Rest, at l =140њ, b =+1њ. ...