ACO 1656

Basic data :
ACO 1656 -- Cluster of Galaxies 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: ClG (2010A&A,ACO,...), X (2A,3A,...), C?G (2014A&A,XCLASS), GrG (RASSCALS,[N93]), gLe (2011A&A), gam (IGR,INTREF), Rad (DB) 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) : 12 59 44.40 +27 54 44.9 (Optical) [ ] D 2020ApJS..246....2A 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) : 12 57 19.64 +28 10 54.4 [ ] 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) : 056.48504 +87.99927 [ ] 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) 6933 [~] / z(spectroscopic) 0.0234 [~] / cz 7015 [~]    (Opt) C 2016ApJ...819...63R 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): 30.0 30.0 ~ (Rad) D 2015ApJ...813...77Y	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: sometimes designated DC 27 (27th cluster in 1980ApJS...42..565D, table 1). Brightest Galaxy of the cluster is NGC 4874 (Hudson et al., 2001MNRAS.327..265H)

ACO 1656	FR 76	PLCKESZ G057.33+88.01	4U 1257+28
2A 1257+283	1H 1257+281	PSZ1 G057.84+87.98	XCLASS 1783
3A 1257+282	H 1257+283	PSZ2 G057.80+88.00	XSS J12596+2759
BAX 194.9531+27.9807	H 1256+27	PSZRX G057.30+88.00	X Com X-1
CAN 90	HMS 1257+2814	RASSCALS NRGb226	[AWK2020] 3
CID 90	IGR J12595+2755	RBS 1198	[B2017] 1599
ClG 1257.4+2815	INTREF 534	RXC J1259.7+2756	[F81] 253
DB 88	1M 1257+281	RX J1259.7+2756	[KRL2007b] 128
2E 2932	2MAXI J1259+279	1RXS J125947.9+275636	[KVC2005] 8
2E 1257.4+2812	MCXC J1259.7+2756	SWIFT J1259.7+2755	[N93] 109
1ES 1257+28.2	NAME Coma Cluster	2U 1257+28	[S85] 222
EXSS 1257.4+2815	PBC J1259.5+2756	3U 1257+28	[SPD2011] 67

References (4694 between 1850 and 2023) (Total 4694) 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

Collections of Measurements

External archives :

Archive data at HEASARC - High-Energy Astrophysics Science Archive Research Center

Data at NED - NASA/IPAC Extragalactic Database : ACO 1656

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