NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-21 T05:40:21 PDT
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Velocity(km/s): Unconstrained
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Parameters for Distances and Cosmology: Ho= 73.0; Ωmatter = 0.27; Ωvacuum = 0.73;
Derived Quantities use a Redshift corrected to a Reference Frame defined by the 3K CMB

Detailed Information for Object No. 1

INDEX for NGC 6921
Essential Data (jump to sub-section of this query report):

   Essential Note    
   Cross-IDs    
   Coordinates    
   Basic Data   
   Quantities Derived from Redshift    
   Redshift-Independent Distances
   Quick-Look Photometry and Luminosities
   Quick-Look Angular and Physical Sizes
   Classifications
   Foreground Galactic Extinction    
   External Services
Detailed Data (NED queries):

Images
   
43 Photometric data point(s) and SED   
Spectra   
Redshift-Independent Distances
71 Reference(s)   
13 Position data point(s)
10 Redshift data point(s)   
6 Diameter data point(s)   
4 Note(s)   
UGC data    
RC3 data    

ESSENTIAL NOTE for NGC 6921 (Back to INDEX)
N/A

CROSS-IDENTIFICATIONS for NGC 6921 (Back to INDEX)
Object Names Type Object Names Type
NGC 6921G UZC J202828.8+254324 G
UGC 11570 G 87GB 202621.8+253300 RadioS
MCG +04-48-001 G NVSS J202828+254325 RadioS
2MASX J20282884+2543241 IrS IGR J20286+2544:[RTC2009] 2 XrayS
2MASS J20282888+2543244 IrS IGR J20286+2544(2) G
PGC 064768 G SWIFT J2028.5+2543b XrayS
SSTSL2 J202828.84+254324.6 IrS [WGB2006] 202624+25330_a G
USNO-B1.0 1157-0462166 VisS [WMR2009] 134 G
     

COORDINATES for NGC 6921 (Back to INDEX)

Position Reference:20032MASX.C.......:

Reference    Frame     Longitude    Latitude        RA           DEC      Uncertainty Ellipse (arcsec)
                       (degrees)   (degrees)                              Semimajor Semiminor  PA(deg)
Equatorial (B1950.0)  306.586418   25.556459  20h26m20.74s  +25d33m23.3s  1.25E+00  1.25E+00    0
Equatorial (J2000.0)  307.120250   25.723417  20h28m28.86s  +25d43m24.3s  1.25E+00  1.25E+00    0
Ecliptic   (B1950.0)  317.487570   43.157551                              1.25E+00  1.25E+00    0
Ecliptic   (J2000.0)  318.181347   43.153550                              1.25E+00  1.25E+00    0
Galactic               66.983282   -7.558412                              1.25E+00  1.25E+00    0
SuperGalactic         324.938305   66.013359                              1.25E+00  1.25E+00    0
Additional detailed measurements with references are also available by clicking below:
13 Position data point(s)

REDSHIFT-INDEPENDENT DISTANCES for NGC 6921 (Back to INDEX)
 N/A 

CLASSIFICATIONS (TYPES, ATTRIBUTES) for NGC 6921 (Back to INDEX)
TypeAs PublishedNED HomogenizedFlagReference Code
HierarchyPin a pair...1976RC2...C...0000d
KinematicsHI line widthHI line width...2003A&A...412...57P
Galaxy MorphologySA(r)0/a:SA0/a?(r)...1991RC3.9.C...0000d
7 Detailed Classification(s)


FOREGROUND GALACTIC EXTINCTION for NGC 6921 (Back to INDEX)
Galactic Extinction from the Schlafly & Finkbeiner 2011, Appendix; 2011ApJ...737..103S (SF11) recalibration 
of the Schlegel, Finkbeiner & Davis 1998, Appendix B; 1998ApJ...500..525S (SFD98) infrared-based dust map.
The map is based on dust emission from COBE/DIRBE and IRAS/ISSA;
the recalibration assumes a Fitzpatrick (1999PASP..111...63F) reddening law with Rv = 3.1 and different source spectrum than SFD98.

L a n d o l tS D S SU K I R T
Filter [µm]U (0.35)B (0.43)V (0.54)R (0.64)I (0.80)u (0.36)g (0.47)r (0.62)i (0.75)z (0.89)J (1.25)H (1.66)K (2.19)L' (3.78)
Aλ [mag]1.9181.6051.2130.9600.6661.8761.4621.0110.7510.5590.3140.1990.1340.068
Show/Hide Aλ magnitudes in all 88 photometric bands based on SF11
For completeness, we include the original SFD98 values:
L a n d o l tS D S SU K I R T
Filter [µm]U (0.34)B (0.44)V (0.54)R (0.65)I (0.81)u (0.35)g (0.49)r (0.63)i (0.78)z (0.93)J (1.27)H (1.67)K (2.22)L' (3.81)
Aλ [mag]2.4191.9211.4761.1900.8642.2951.6891.2250.9290.6580.4020.2560.1630.068

See Notes on Galactic Extinction for important caveats.

BASIC DATA for NGC 6921 (Back to INDEX)
Helio. Radial Velocity     :      4337 +/-       10 km/s      
Redshift                   :  0.014467 +/- 0.000033        2003A&A...412...57P
Major Diameter (arcmin)    :   0.9
Minor Diameter (arcmin)    :   0.2
Magnitude and Filter       : 14.4 
Classifications            : SA(r)0/a:      Sy2  

NOTE: This information is indicative only. With the exception of the
      redshift they are unreferenced and highly inhomogeneous as to
      their origin. The Radial Velocity (when available) is computed
      from the listed redshift. The remaining values are designed to
      orient the user with a quick-look, overall assessment of the
      general properties of the object in question. They are not
      averages nor are they standardized in any way.
Additional detailed measurements with references are also available by clicking below:
10 Redshift data point(s)      43 photometric data point(s)      6 Diameter data point(s)      

QUANTITIES DERIVED FROM REDSHIFT for NGC 6921 (Details)(Back to INDEX)
Calculated and Corrected Velocities
V (Heliocentric)           :    4337 +/-     10 km/s      2003A&A...412...57P
V (Kinematic LSR)          :    4354 +/-     10 km/s      1986MNRAS.221.1023K
V (Galactocentric GSR)     :    4551 +/-     13 km/s      1991RC3.9.C...0000d
V (Local Group)            :    4621 +/-     20 km/s      1996AJ....111..794K
V (3K CMB)                 :    4067 +/-     21 km/s      1996ApJ...473..576F
V (Virgo Infall only)      :    4590 +/-     20 km/s      2000ApJ...529..786M
V (Virgo + GA only)        :    4593 +/-     20 km/s      2000ApJ...529..786M
V (Virgo + GA + Shapley)   :    4604 +/-     20 km/s      2000ApJ...529..786M

Hubble Flow Distance and Distance Modulus (where Ho =   73.0 +/-   5 km/sec/Mpc)
D (Galactocentric GSR)     :    62.3 +/-    4.4 Mpc      (m-M) = 33.97 +/- 0.15 mag
D (Local Group)            :    63.3 +/-    4.4 Mpc      (m-M) = 34.01 +/- 0.15 mag
D (3K CMB)                 :    55.7 +/-    3.9 Mpc      (m-M) = 33.73 +/- 0.15 mag
D (Virgo Infall only)      :    62.9 +/-    4.4 Mpc      (m-M) = 33.99 +/- 0.15 mag
D (Virgo + GA only)        :    62.9 +/-    4.4 Mpc      (m-M) = 33.99 +/- 0.15 mag
D (Virgo + GA + Shapley)   :    63.1 +/-    4.4 Mpc      (m-M) = 34.00 +/- 0.15 mag

Scale at Hubble Flow Distances
Scale (Galactocentric GSR) :     302 pc/arcsec =  0.302 kpc/arcsec =  18.14 kpc/arcmin =   1.09 Mpc/degree
Scale (Local Group)        :     307 pc/arcsec =  0.307 kpc/arcsec =  18.41 kpc/arcmin =   1.10 Mpc/degree
Scale (3K CMB)             :     270 pc/arcsec =  0.270 kpc/arcsec =  16.20 kpc/arcmin =   0.97 Mpc/degree
Scale (Virgo Infall only)  :     305 pc/arcsec =  0.305 kpc/arcsec =  18.29 kpc/arcmin =   1.10 Mpc/degree
Scale (Virgo + GA only)    :     305 pc/arcsec =  0.305 kpc/arcsec =  18.30 kpc/arcmin =   1.10 Mpc/degree
Scale(Virgo + GA + Shapley):     306 pc/arcsec =  0.306 kpc/arcsec =  18.35 kpc/arcmin =   1.10 Mpc/degree

To Search for Nearby Objects (Physical Companions): Enter Your Preferred Values and click on "Submit Environment Search" button
Search for Objects within +/-arcmin where 100 kpc = 5.451 arcmin and Selected Redshift, defined by the Velocity Range: from to km/sec where V(Heliocentric) = 4337 km/sec
Cosmology-Corrected Quantities [Ho = 73.00 km/sec/Mpc, Ωmatter = 0.27, Ωvacuum = 0.73] [Redshift 0.013565 as corrected to the Reference Frame defined by the 3K Microwave Background Radiation] Luminosity Distance : 56.3 Mpc (m-M) = 33.75 mag Angular-Size Distance : 54.8 Mpc (m-M) = 33.69 mag Co-Moving Radial Distance : 55.6 Mpc (m-M) = 33.72 mag Co-Moving Tangential Dist. : 55.6 Mpc (m-M) = 33.72 mag Co-Moving Volume : 0.000718 Gpc^3 Light Travel-Time : 0.180 Gyr Age at Redshift 0.013565 : 13.119 Gyr Age of Universe : 13.299 Gyr Scale (Cosmology Corrected): 266 pc/arcsec = 0.266 kpc/arcsec = 15.94 kpc/arcmin = 0.96 Mpc/degree Surface Brightness Dimming : Flux Density per Unit Area = 0.94753; Magnitude per Unit Area = 0.05852 mag
To change Cosmological Input Parameters for Derived Quantities: Enter Your Preferred Values and click on "Submit Changed Hubble Parameters for this object" button
HoΩmatterΩvacuum     
Correct Redshift To the Reference Frame defined by: as Input for Calculation of the Distances and Cosmology-Corrected Quantities

QUICK-LOOK PHOTOMETRY and LUMINOSITIES for NGC 6921 (Back to INDEX)

The brightest flux in each of the following spectral regions, when available:
Gamma-Ray (ν > 2E19 Hz); X-Ray (2E19 Hz > ν > 2E16 Hz); Ultraviolet (2E16 Hz > ν > 9E14 Hz); Visual (9E14 Hz > ν > 3E14 Hz);
Near-Infrared (3E14 Hz > ν > 6E13 Hz); Mid-Infrared (6E13 Hz > ν > 7.5E12 Hz); Far-Infrared (7.5E12 Hz > ν > 1E12 Hz);
Sub-Millimeter (1E12 Hz > ν > 3E11 Hz); Millimeter (3E11 Hz > ν > 3E10 Hz); Radio (3E10 Hz > ν).

Spectral
Region
Band Apparent Mag or Flux Refcode Absolute Mag or νLν [W] νLν [L(Bolometric)]
Gamma-Ray14-195 keV (Swift) 6.1E-11 erg/cm^2^/s 2008ApJ...681..113T 2.31E+36 [W] 6.02E+09
X-Ray2-10 keV (XMM) 2.53E-12 ergs/cm^2^/s 2008ApJ...674..686W 9.57E+34 [W] 2.49E+08
VisualV (V_T^0) 11.71 mag 1991RC3.9.C...0000d-22.04 [mag] 4.03E+10
Near-InfraredH 9.180 +/- 0.019 mag 20032MASX.C.......:-24.57 +/- 0.50 [mag] 3.91E+10 +/- 7.86E+09
Mid-Infrared25 microns (IRAS) 0.62 +/- 0.20 Jy 2004AJ....127.3235S 2.82E+36 +/- 1.07E+36 [W] 7.34E+09 +/- 2.79E+09
Far-Infrared100 microns (IRAS) 7.48 +/- 2.30 Jy 2004AJ....127.3235S 8.51E+36 +/- 3.12E+36 [W] 2.21E+10 +/- 8.12E+09
Radio1.4GHz 28.2 +/- 1.2 milliJy 1998AJ....115.1693C 1.50E+31 +/- 3.06E+30 [W] 3.90E+04 +/- 7.97E+03
NOTE: The above quantities are derived using a Distance Modulus of 33.75 mag corresponding to
a Luminosity Distance of 56.3 Mpc [assuming 10%uncertainty] using the Cosmology-Corrected Quantities.
The quantities quoted above have not necessarily been corrected for foreground extinction, and no K-Corrections have been applied.

View details and SED for 43 Photometric data point(s) available in NED.

QUICK-LOOK ANGULAR & PHYSICAL DIAMETERS for NGC 6921 (Back to INDEX)

The largest diameters in the Visual and Near-Infrared spectral regions, when available:

Passband Apparent Major Axis
(2a) [arcsec]
Apparent Minor Axis
(2b) [arcsec]
PA
[degrees]
(J2000.0)
Reference Level RefcodePhysical Major Axis
(2a) [kpc]
Physical Minor Axis
(2b) [kpc]
RC3 D_0 (blue) 70.50...... 25.0 B-mag arcsec^-2^ 1991RC3.9.C...0000d21.56...
K_s (2MASS "total") 106.5044.73140 Diameter for "total" magnitude 20032MASX.C.......:20032MASX.C.......:32.5713.68
NOTE: At z <= 0.5, physical diameters are derived using a Scale at the Hubble Flow Distance (Virgo + GA + Shapley) of 0.306 kpc/arcsec.
The quantities quoted above have not necessarily been corrected for foreground extinction.

View details for 6 Diameter data point(s) available in NED.

EXTERNAL ARCHIVES AND SERVICES for NGC 6921 Help (Back to INDEX)
Resources for Object NamesSite/Service
Query SIMBAD by primary NED object name -- NGC 6921SIMBAD (CDS, Strasbourg, France)
Revised New General Catalogue -- NGC 6921VizieR Catalog Query (U.S. mirror, CfA/Harvard)
Uppsala General Catalog -- UGC 11570 VizieR Catalog Query (U.S. mirror, CfA/Harvard)
Morphological Catalog of Galaxies -- MCG +04-48-001 VizieR Catalog Query (U.S. mirror, CfA/Harvard)
2MASS Extended Source Images (JHKs) -- 2MASX J20282884+2543241 NASA/IPAC Infrared Science Archive (IRSA)
Catalogue of Principal Galaxies -- PGC 064768 VizieR Catalog Query (U.S. mirror, CfA/Harvard)
Retrieve mean data from LEDA -- PGC 064768 The Lyon/Meudon Extragalactic Database (LEDA)
Query UZC Spectral Archive (60 arcsec search radius)Updated Zwicky Catalog Data (Harvard/SAO)
NRAO/VLA Sky Survey (NVSS)
Query GALEX (NUV/FUV) Mission Archive (7.2 arcsec search radius) -- NGC 6921GALEX Mission Data Archive at MAST
Explore IRSA resources with RADAR (10 arcsec search radius) -- NGC 6921NASA/IPAC Infrared Science Archive (IRSA)
Resources for position 20h28m28.8s, +25d43m24s (J2000)Site/Service
Query Optical and UV Mission Archives (Default search radius)Multimission Archive at STScI (MAST)
Query High Energy Mission Archives (Default search radius)HEASARC (NASA/GSFC)
Query IRSA for WISE images (10 arcmin search radius)NASA/IPAC Infrared Science Archive (IRSA)
Band(s): Size:
NASA/IPAC Infrared Science Archive (IRSA)
Band(s): Size:
NASA/IPAC Infrared Science Archive (IRSA)
NASA/IPAC Infrared Science Archive (IRSA)
 Size:    Contours (PS)  JPEG  FITS File 
NRAO/VLA Sky Survey (NVSS)
The NRAO Data Archive System





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