NGC491

Basic data :
NGC 491 -- Seyfert 2 Galaxy Origin of the objects types : (Ref) Object type as listed in the reference "Ref" (acronym) Object type linked to the acronym according to the original reference () Anterior to 2007, before we can link the objet type to a reference, or given by the CDS team in some particular cases Other object types: G (2016A&A,APMBGC,...), Rad (GLEAM,NVSS,...), IR (IRAS,ISOSS,...), GiG ([CHM2007],[ZM98]), * (GSC,Gaia), Sy2 (2022ApJS), LIN (2022ApJS), AG? (2020MNRAS) Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" : ra dec : right ascension and declination (unit and frame defined according to your Output Options) Grey values are increasing the original precision due to the computation of frame transformations (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam) [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue), position angle (in degrees North celestial pole to East) quality : flag of quality E ≥ 10" D : 1-10" (and some old data) C : 0.1-1" B : 0.01-0.1" + 2MASS, Tyc A : VLBI, Hipparcos bibcode : bibcode of the coordinates reference ICRS coord. (ep=J2000) : 01 21 20.4255944904 -34 03 48.032689104 (Optical) [ 0.7692 0.6545 90 ] C 2020yCat.1350....0G Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" : ra dec : right ascension and declination (unit and frame defined according to your Output Options) Grey values are increasing the original precision due to the computation of frame transformations (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam) [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue), position angle (in degrees North celestial pole to East) quality : flag of quality E ≥ 10" D : 1-10" (and some old data) C : 0.1-1" B : 0.01-0.1" + 2MASS, Tyc A : VLBI, Hipparcos bibcode : bibcode of the coordinates reference FK4 coord. (ep=B1950 eq=1950) : 01 19 02.2323246998 -34 19 29.779895468 [ 0.7692 0.6545 90 ] Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" : ra dec : right ascension and declination (unit and frame defined according to your Output Options) Grey values are increasing the original precision due to the computation of frame transformations (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam) [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue), position angle (in degrees North celestial pole to East) quality : flag of quality E ≥ 10" D : 1-10" (and some old data) C : 0.1-1" B : 0.01-0.1" + 2MASS, Tyc A : VLBI, Hipparcos bibcode : bibcode of the coordinates reference Gal coord. (ep=J2000) : 261.9245335290401 -80.5456853612363 [ 0.7692 0.6545 90 ] Syntax of radial velocity (or/and redshift) is : "value [error] (wavelength) quality bibcode" value : radial velocity or/and redshift (Heliocentric frame) according to your Output Options (redshift may be not displayed if the data value is <0 and the database inside value is a radial velocity) [error] : error of the corresponding value displayed before (wavelength) : wavelength range of the measurement : Rad, mm, IR, Opt, UV, Xray, Gam or  '∼'(unknown) quality : flag of quality ( A=best quality -> E=worst quality, ∼=unknown quality) bibcode : bibcode of the value's origin Radial velocity / Redshift / cz : V(km/s) 3859 [17] / z(~) 0.012956 [0.000057] / cz 3884.11 [17.09]    D 2002LEDA.........0P Syntax of morphological type is : mtype quality bibcode mtype : Hubble morphological class (spirals, ellipticals, etc) quality : flag of quality (A=best quality -> E=worst quality, {� } =unknown quality) bibcode : bibcode of the morphological type reference Morphological type: 3.0 D 1989ESOLV.C......0L Syntax of angular size is : "maj-axis min-axis angle (wtype) quality bibcode" maj-axis : major axis size (arc minutes) min-axis : minor axis size (arc minutes) angle : orientation angle (in degrees) (wtype) : wavelength class for the origin of the angular size (Rad, mm, IR, Opt, UV, Xray, Gam) quality : flag of quality of the angular size values ( A=best quality -> E=worst quality, {� } =unknown quality) bibcode : bibcode of the angular size reference Angular size (arcmin): 0.917 0.660 95 (NIR) C 2006AJ....131.1163S Syntax of fluxes (or magnitudes) is : "filter-name (System) flux-value [error] quality MultVarFlags bibcode" filter-name : U, B, V, R, I, G, J, H, K, u, g, r, i, z (System) : may be AB (default is Vega) flux-value : value of flux or magnitude [error] : error value quality : flag of quality of the flux value ( A=best quality -> E=worst quality, {� } =unknown quality) MultVarFlags : Mult is zero or one char (J) for joined photometry ; Var can be zero or two chars (V[0-4]) bibcode : bibcode of the flux reference Fluxes (8) : U 13.22 [0.15] D 2007ApJS..173..185G B 13.28 [~] C 1989ESOLV.C......0L V 12.54 [0.15] D 2007ApJS..173..185G R 11.82 [~] C 1989ESOLV.C......0L G 19.000746 [0.011725] C 2020yCat.1350....0G J 10.351 [0.016] C 2006AJ....131.1163S H 9.698 [0.020] C 2006AJ....131.1163S K 9.388 [0.025] C 2006AJ....131.1163S	SIMBAD within arcmin ', {sourceSize:12, color:'#30a090'})); aladin.on('objectClicked', function(object) { var objName=object.data.MAIN_ID; aladin.showPopup(object.ra,object.dec,'',''+ objName+''); });" title="Show Simbad objects"> Overlay points in this preview 2MASS DSS SDSSXMMIRACIRISGALEX All (CDSPortal) Send to within arcsec The VizieR photometry tool allows for easy visualization of photometry points extracted around the Simbad position from photometry-enabled catalogues in VizieR. The search radius has to be specified by the user. It is currently limited to a maximum of 30 arcsec. It depends mostly on the precision or quality of the coordinates (SIMBAD and VizieR catalogs), the resolution of the images from which the sources were extracted, source extent, and source crowding. Suggestions are: crowded field: 0.5 to 1.5 arcsec, 3 arcsec otherwise; uncertain coordinates (SIMBAD quality E or coordinates without reference): 5 to 30 arsec (risky!).
Some important notes on this object about identifications and objects associations. notes: See GALEX UV data in GALEX data

NGC 491	GSC 07004-01064	2MASX J01212042-3403477	TGSSADR J012120.5-340347
APMBGC 352-077-039	GSN 1	MCG-06-04-011	[CHM2007] LDC 78 J012120.42-3403477
6dFGS gJ012120.4-340348	IRAS 01190-3419	NVSS J012120-340350	[SLK2004] 186
ESO 352-53	IRAS F01190-3419	PSCz Q01190-3419	[ZM98] NGC 491 1
ESO-LV 352-0530	ISOSS J01213-3404	SGC 011902-3419.5	Gaia DR2 5014446542251471744
GLEAM J012121-340343	LEDA 4914	SUMSS J012120-340345	Gaia DR3 5014446546546701312

References (64 between 1850 and 2024) (Total 64) Simbad bibliographic survey began in 1850 for stars (at least bright stars) and in 1983 for all other objects (outside the solar system). Follow new references on this object

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External archives :

Data at NED - NASA/IPAC Extragalactic Database : NGC491

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