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Date and Time of the Query: 2018-07-19 T00:41:55 PDT
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Diameter data point(s) for object NGC 6946

Diameter Data --- Published and Homogenized (arcsec) Units

  Published UnitsHomogenized Units
No.Observed Passband
REFCODE
Major Axis
(2a)
Major Axis UnitsMinor Axis
(2b)
Minor Axis UnitsAxis Ratio (b/a)Major Axis Unc.Ellipticity
(1 - b/a)
Eccentricity
[(a/b)2-1]/
[(a/b)2+1]
Position Angle
(deg)
[published]
Reference LevelFrequency (Hz)Major Axis
(2a)
(arcsec)
Major Axis Unc.Axis Ratio (b/a)Ellipticity
(1 - b/a)
Eccentricity
[(a/b)2-1]/
[(a/b)2+1]
cos-1(b/a)
(deg)
Position Angle
(deg)
[J2000]
1 POSS1 103a-O
1973UGC...C...0000N
14.00 arcmin 14.00 arcmin ... ... ... ... ... About 25.0 B-mag arcsec^-2^ 7.40E+14 840.00 ... 1.00 0.00 0.00 0 ...
2 POSS1 103a-O
1962MCG1..C...0000V
0.50 arcmin 0.50 arcmin ... ... ... ... ... High surface brightness 7.40E+14 30.00 ... 1.00 0.00 0.00 0 ...
3 POSS1 103a-O
1962MCG1..C...0000V
9.00 arcmin 9.00 arcmin ... ... ... ... ... Intermed. surface brightness 7.40E+14 540.00 ... 1.00 0.00 0.00 0 ...
4 RC3 D_25, R_25 (blue)
1991RC3.9.C...0000d
2.06 log(2a) + 1 ... ... 0.07
log(a/b)
0.01 ... ... ... 25.0 B-mag arcsec^-2^ 6.81E+14 688.90 16.00 0.85 0.15 0.16 32 ...
5 RC3 A_e (Johnson B)
1991RC3.9.C...0000d
1.78 log(2a) + 1 ... ... ... 0.02 ... ... ... ... 6.81E+14 361.50 17.00 ... ... ... ... ...
6 RC3 D_0 (blue)
1991RC3.9.C...0000d
2.22 log(2a) + 1 ... ... ... ... ... ... ... 25.0 B-mag arcsec^-2^ 6.81E+14 995.80 ... ... ... ... ... ...
7 K_s (LGA/2MASS isophotal)
2003AJ....125..525J
252.5 (a) arcsec ... ... 0.700 (b/a) ... ... ... 52.5
[J2000]
20.0 K-mag arcsec^-2^ 1.38E+14 505.00 ... 0.70 0.30 0.34 46 53
[J2000]
8 K_s (LGA/2MASS "total")
2003AJ....125..525J
479.0 (a) arcsec ... ... 0.700 (b/a) ... ... ... 52.5
[J2000]
Diameter for "total" magnitude 1.38E+14 958.00 ... 0.70 0.30 0.34 46 53
[J2000]


Detailed Information for Each Entry

 No. 1
                                Published Units:                    Homogenized Units:

Reference Code                : 1973UGC...C...0000N
Published Object Name         : UGC 11597                     
Frequency Targeted            : POSS1 103a-O                  
Major Axis (2a)               : 14.00      arcmin                   2a = 840.00 arcsec
Uncertainty                   : ...                                 ... 
Minor Axis (2b)               : 2b = 14.00      arcmin              2b = 840.00 arcsec 
Uncertainty                   : ...                                 ...
Axis Ratio                    : ...                                 b/a = 1.00
Uncertainty                   : ...                                 ...
Ellipticity                   : ...                                 1 - b/a = 0.00
Uncertainty                   : ...                                 ...
Eccentricity                  : ...                                 [(a/b)2-1]/[(a/b)2+1] = 0.00
Uncertainty                   : ...                                 ...
Cos-1(b/a)                    : ...                                 0 deg
Position Angle [Equinox]      : ...                                 ...
Uncertainty                   : ...                                 ...
Significance                  : No uncertainty reported
Diameter Reference Level      : About 25.0 B-mag arcsec^-2^   
Frequency                     : 4050         A                      7.40E+14 Hz
Frequency Mode                : Broad-band detector (e.g. photographic plate)

Measurement Mode               
    Detector Type             : Photographic plate, print, or film
    Fitting Technique         : Eye estimate
    Measured Quantity         : "Outer" diameter
Coordinates Targeted          : 203348.         +595900.    (B1950)
Qualifiers                    : From new, raw data
NED Comment                   :                                         

No. 2 Published Units: Homogenized Units: Reference Code : 1962MCG1..C...0000V Published Object Name : MCG +10-29-006 Frequency Targeted : POSS1 103a-O Major Axis (2a) : 0.50 arcmin 2a = 30.00 arcsec Uncertainty : ... ... Minor Axis (2b) : 2b = 0.50 arcmin 2b = 30.00 arcsec Uncertainty : ... ... Axis Ratio : ... b/a = 1.00 Uncertainty : ... ... Ellipticity : ... 1 - b/a = 0.00 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.00 Uncertainty : ... ... Cos-1(b/a) : ... 0 deg Position Angle [Equinox] : ... ... Uncertainty : ... ... Significance : No uncertainty reported Diameter Reference Level : High surface brightness Frequency : 4050 A 7.40E+14 Hz Frequency Mode : Broad-band detector (e.g. photographic plate) Measurement Mode Detector Type : Photographic plate, print, or film Fitting Technique : Eye estimate Measured Quantity : "Inner" diameter Coordinates Targeted : 203336 +5958 (B1950) Qualifiers : From new, raw data NED Comment :
No. 3 Published Units: Homogenized Units: Reference Code : 1962MCG1..C...0000V Published Object Name : MCG +10-29-006 Frequency Targeted : POSS1 103a-O Major Axis (2a) : 9.00 arcmin 2a = 540.00 arcsec Uncertainty : ... ... Minor Axis (2b) : 2b = 9.00 arcmin 2b = 540.00 arcsec Uncertainty : ... ... Axis Ratio : ... b/a = 1.00 Uncertainty : ... ... Ellipticity : ... 1 - b/a = 0.00 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.00 Uncertainty : ... ... Cos-1(b/a) : ... 0 deg Position Angle [Equinox] : ... ... Uncertainty : ... ... Significance : No uncertainty reported Diameter Reference Level : Intermed. surface brightness Frequency : 4050 A 7.40E+14 Hz Frequency Mode : Broad-band detector (e.g. photographic plate) Measurement Mode Detector Type : Photographic plate, print, or film Fitting Technique : Eye estimate Measured Quantity : "Outer" diameter Coordinates Targeted : 203336 +5958 (B1950) Qualifiers : From new, raw data NED Comment :
No. 4 Published Units: Homogenized Units: Reference Code : 1991RC3.9.C...0000d Published Object Name : UGC 11597 Frequency Targeted : RC3 D_25, R_25 (blue) Major Axis (2a) : log(2a) + 1 = 2.06 2a = 688.90 arcsec Uncertainty : 0.01 16.00 arcsec Minor Axis (2b) : ... 2b = 586.25 arcsec Uncertainty : ... ... Axis Ratio : log(a/b) = 0.07 b/a = 0.85 Uncertainty : 0.02 0.04 Ellipticity : ... 1 - b/a = 0.15 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.16 Uncertainty : ... ... Cos-1(b/a) : ... 32 deg Position Angle [Equinox] : ... ... Uncertainty : ... ... Significance : Mean error Diameter Reference Level : 25.0 B-mag arcsec^-2^ Frequency : 4400 A 6.81E+14 Hz Frequency Mode : Broad-band detector (e.g. photographic plate) Measurement Mode Detector Type : Photographic plate, print, or film Fitting Technique : Eye estimate Measured Quantity : Isophotal diameter Coordinates Targeted : 203452.0 +600915. (J2000) Qualifiers : Homogenized from previously published data NED Comment :
No. 5 Published Units: Homogenized Units: Reference Code : 1991RC3.9.C...0000d Published Object Name : UGC 11597 Frequency Targeted : RC3 A_e (Johnson B) Major Axis (2a) : log(2a) + 1 = 1.78 2a = 361.50 arcsec Uncertainty : 0.02 17.00 arcsec Minor Axis (2b) : ... ... Uncertainty : ... ... Axis Ratio : ... ... Uncertainty : ... ... Ellipticity : ... ... Uncertainty : ... ... Eccentricity : ... ... Uncertainty : ... ... Cos-1(b/a) : ... ... Position Angle [Equinox] : ... ... Uncertainty : ... ... Significance : Mean error Diameter Reference Level : ... Frequency : 4400 A 6.81E+14 Hz Frequency Mode : Broad-band detector (e.g. photographic plate) Measurement Mode Detector Type : Photographic plate, print, or film Fitting Technique : Eye estimate Measured Quantity : Isophotal diameter Coordinates Targeted : 203452.0 +600915. (J2000) Qualifiers : From new, raw data NED Comment : From magnitude-aperture curves.
No. 6 Published Units: Homogenized Units: Reference Code : 1991RC3.9.C...0000d Published Object Name : UGC 11597 Frequency Targeted : RC3 D_0 (blue) Major Axis (2a) : log(2a) + 1 = 2.22 2a = 995.80 arcsec Uncertainty : ... ... Minor Axis (2b) : ... ... Uncertainty : ... ... Axis Ratio : ... ... Uncertainty : ... ... Ellipticity : ... ... Uncertainty : ... ... Eccentricity : ... ... Uncertainty : ... ... Cos-1(b/a) : ... ... Position Angle [Equinox] : ... ... Uncertainty : ... ... Significance : No uncertainty reported Diameter Reference Level : 25.0 B-mag arcsec^-2^ Frequency : 4400 A 6.81E+14 Hz Frequency Mode : Broad-band detector (e.g. photographic plate) Measurement Mode Detector Type : Photographic plate, print, or film Fitting Technique : Eye estimate Measured Quantity : Isophotal diameter Coordinates Targeted : 203452.0 +600915. (J2000) Qualifiers : Homogenized from previously published data NED Comment : Extinction and inclination corrected.
No. 7 Published Units: Homogenized Units: Reference Code : 2003AJ....125..525J Published Object Name : NGC 6946 Frequency Targeted : K_s (LGA/2MASS isophotal) Major Axis (2a) : a = 252.5 arcsec 2a = 505.00 arcsec Uncertainty : ... ... Minor Axis (2b) : ... 2b = 353.50 arcsec Uncertainty : ... ... Axis Ratio : b/a = 0.700 b/a = 0.70 Uncertainty : ... ... Ellipticity : ... 1 - b/a = 0.30 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.34 Uncertainty : ... ... Cos-1(b/a) : ... 46 deg Position Angle [Equinox] : 52.5 deg [J2000] 53 deg [J2000] Uncertainty : ... ... Significance : No uncertainty reported Diameter Reference Level : 20.0 K-mag arcsec^-2^ Frequency : 2.17 microns 1.38E+14 Hz Frequency Mode : Broad-band detector (e.g. photographic plate) Measurement Mode Detector Type : Maps (e.g., 2MASS, VLA, Sloan) Fitting Technique : Ellipse fitting to image Measured Quantity : Isophotal diameter Qualifiers : A radius is given in DIA_MAJ, not a diameter Coordinates Targeted : 308.718048 60.153679 (J2000) Qualifiers : From new, raw data NED Comment :
No. 8 Published Units: Homogenized Units: Reference Code : 2003AJ....125..525J Published Object Name : NGC 6946 Frequency Targeted : K_s (LGA/2MASS "total") Major Axis (2a) : a = 479.0 arcsec 2a = 958.00 arcsec Uncertainty : ... ... Minor Axis (2b) : ... 2b = 670.60 arcsec Uncertainty : ... ... Axis Ratio : b/a = 0.700 b/a = 0.70 Uncertainty : ... ... Ellipticity : ... 1 - b/a = 0.30 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.34 Uncertainty : ... ... Cos-1(b/a) : ... 46 deg Position Angle [Equinox] : 52.5 deg [J2000] 53 deg [J2000] Uncertainty : ... ... Significance : No uncertainty reported Diameter Reference Level : Diameter for "total" magnitude Frequency : 2.17 microns 1.38E+14 Hz Frequency Mode : Broad-band detector (e.g. photographic plate) Measurement Mode Detector Type : Maps (e.g., 2MASS, VLA, Sloan) Fitting Technique : Ellipse fitting to image Measured Quantity : Isophotal diameter Qualifiers : A radius is given in DIA_MAJ, not a diameter Coordinates Targeted : 308.718048 60.153679 (J2000) Qualifiers : From new, raw data NED Comment :

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