Home     Getting Started     To Survive in the Universe    
Inhabited Sky
    News@Sky     Astro Photo     The Collection     Forum     Blog New!     FAQ     Press     Login  

NGC 4195


Contents

Images

Upload your image

DSS Images   Other Images


Related articles

The Second Byurakan Survey. General Catalogue
The Second Byurakan Survey (SBS) General Catalogue is presented. TheSBS, a continuation of the Markarian survey reaching fainter limitingmagnitudes, is the first survey which combines the search of galaxiesand QSOs. A total area of 991OS#square;degrees of the Northern sky wascovered with the use of three objective prisms in combination withSchott filters. The limited magnitude on the best plates reached B ~19.5.The General Catalogue consists of 3563 objects presented in two parts: aCatalogue of galaxies (1863 objects) and one of stellar objects (1700objects). The Catalogue of SBS AGN consists of 761 objects (155 SyG, 596QSOs, and 10 BLLac). Multi-wavelength data are presented for 1438 SBSobjects identified with X-ray, IRAS and FIRST sources.Spectrophotometric observations obtained over 26 years are available for3132 objects. Redshifts were measured for ~ 2100 extragalactic objects.Spectral classification is presented for ~ 2970 objects. The majority ofthe data is presented here for the first time. The Catalogue presentsnew large homogeneous deep representative complete samples of brightQSOs, AGNs, and faint UVX galaxies in the Northern sky. The SBS sampleis found to be complete at 70% for galaxies and ~ 85% for AGN/QSOs withB ≤ 17.5.

A search for Low Surface Brightness galaxies in the near-infrared. I. Selection of the sample
A sample of about 3800 Low Surface Brightness (LSB) galaxies wasselected using the all-sky near-infrared (J, H and Ks-band)2MASS survey. The selected objects have a mean central surfacebrightness within a 5'' radius around their centre fainter than 18 magarcsec-2 in the Ks band, making them the lowestsurface brightness galaxies detected by 2MASS. A description is given ofthe relevant properties of the 2MASS survey and the LSB galaxy selectionprocedure, as well as of basic photometric properties of the selectedobjects. The latter properties are compared to those of other samples ofgalaxies, of both LSBs and ``classical'' high surface brightness (HSB)objects, which were selected in the optical. The 2MASS LSBs have aBT_c-KT colour which is on average 0.9 mag bluerthan that of HSBs from the NGC. The 2MASS sample does not appear tocontain a significant population of red objects.All tables and Figs. 2a-c are only available in electronic form athttp://www.edpsciences.org

Environment status of blue compact galaxies and trigger of star formation
The work studies of the environment of low-mass galaxies with activestar formation (SF) and a possible trigger of SF bursts due togravitational interaction. Following the study by Taylor et al. (1995),we extend the search for possible disturbing galaxies of various massesto a much larger sample of 86 BCGs from the sky region of the SecondByurakan survey (SBS). The BCG magnitudes and radial velocities arerevised and up-dated. The sample under study is separated by thecriteria: EW([O III]λ5007) > 45 Å andVh < 6,000 kms and should be representative of alllow-mass galaxies which experience SF bursts. We argue that the moderatetidal disturbers should be taken into account, and incorporate therespective range of distances in the search for disturbing neighbours.The majority of the neighbours in the vicinity of the studied BCGs arefound through the study of their environment among UZC (Falco et al.\cite{Falco99}) galaxies, and the follow-up careful search of thefainter galaxies in the NED database. For the remaining BCGs, theneighbouring galaxies are found based on the results of the SAO 6mtelescope spectroscopy. By studing the data on the radial velocities ofgalaxies in the vicinity of BCGs we found: 1) 33 of the studied BCGs(~38.5%) are associated with significantly brighter galaxies (Δ B>= 1.5m); 2) 23 BCGs (~26.5%) have neighbours either ofcomparable or significantly lower brightness; 3) 14 of the studied BCGs(16\%) with no evident associated galaxy are either certain, orprobable, mergers. Summarizing, we conclude that in ~80% (or more) BCGsfrom the studied sample, the SF bursts are triggered either by tidalaction of various strengths from other galaxies, or due to mergers oflow-mass galaxies. We briefly discuss the implications of our mainconclusion for evolutionary links of BCGs to other types of low-massgalaxies. Part of our sample falls into the volume belonging to theLocal Supercluster. Therefore we formulate the results separately on the``Local Supercluster volume'' and ``general field region''. The totalfractions of BCGs likely triggered by interaction with other galaxy arerespectively, ~84.5% and 80% for the nearby volume and for the generalfield. The fractions of BCGs with significantly brighter disturbers inthese two groups are seemingly different (~54±14% vs.~31.5±7%, respectively). Among the so called ``isolated'' BCGs(that is, without a bright neighbouring galaxy) in both the LocalSupercluster volume and in general field, ~43±10% are probablydisturbed by dwarf galaxies and ~26±8% have a merger morphology.In the Appendix we present the results of the spectroscopy with the SAO6m telescope of 27 galaxies in an attempt to find possible disturbinggalaxies in the vicinity of some of the sample BCGs. Tables 2, 3 and A.1with their notes and Figs. A.1-A.3 are only available in electronic format http://www.edpsciences.org

Accurate optical positions for 2978 objects from the Second Byurakan Survey (SBS) with the Digitized Sky Survey
Optical positions of 2978 objects listed in the Second Byurakan Survey(SBS) were obtained using the Digitized Sky Survey (DSS), and are givenwith an rms uncertainty ~ 1 arcsec in each coordinate. Tables 1 and 2are only available in electronic form at the CDS via anonymous ftp130.79.128.5 or via http://cdsweb.u-strasbg.fr/Abstract.html

Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.

Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).

HI observations of blue compact galaxies from the first and second Byurakan surveys
We present the results of a neutral hydrogen survey of 79 galaxies froma statistical sample of 88 Blue Compact Galaxies (BCGs) selected fromthe First and Second Byurakan objective prism surveys to have a HIIregion-like spectrum, an equivalent width of the [O III] lambda 5007line larger than ~ 50 Å, and a velocity <= 6000 km s(-1) . Thedetection rate for the statistical sample is 74%. HI masses rangebetween 4 10(7)M_sun) and 5 10(9) M_sun with the HI mass distributionpeaking at 3 10(8) M_sun. The full width at half-maximum of the HIprofile varies between ~ 30 km s(-1) and 160 km s(-1) , with a mean of ~92 km s(-1) . These small widths are characteristic of dwarf galaxies.For comparison, we have also observed an additional 92 BCGs with weakerstar formation and/or larger distances, and/or interesting astrophysicalproperties. These in general have larger widths and HI masses.Tables~1,~2,~3 also available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html

Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com

Spectral Observations of Faint Markarian Galaxies of the Second Byurakan Survey
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....113.1527C&db_key=AST

Observational Data for the Kinematics of the Local Universe - Part Two - Second Set of Radial Velocity Measurements
This paper is the second one in a series dedicated to the study of thekinematics of the local universe. It gives 361 new optical and radioredshifts measured at ESO, OHP and Nancay Observatories.

Submit a new article


Related links

  • - No Links Found -
Submit a new link


Member of following groups:


Observation and Astrometry data

Constellation:Ursa Major
Right ascension:12h14m18.20s
Declination:+59°36'53.0"
Aparent dimensions:1.514′ × 1.349′

Catalogs and designations:
Proper Names   (Edit)
NGC 2000.0NGC 4195
HYPERLEDA-IPGC 39082

→ Request more catalogs and designations from VizieR