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Date and Time of the Query: 2019-02-16 T18:30:47 PST
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Diameter data point(s) for object NGC 2918

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
1.40 arcmin 1.00 arcmin ... ... ... ... 65
[B1950]
About 25.0 B-mag arcsec^-2^ 7.40E+14 84.00 ... 0.71 0.29 0.32 44 65
[J2000]
2 K_s (2MASS isophotal)
20032MASX.C.......:
31.6 (a) arcsec ... ... 0.700 (b/a) ... ... ... 50
[J2000]
20.0 K-mag arcsec^-2^ 1.38E+14 63.20 ... 0.70 0.30 0.34 46 50
[J2000]
3 K_s (2MASS "total")
20032MASX.C.......:
47.5 (a) arcsec ... ... 0.700 (b/a) ... ... ... 50
[J2000]
Diameter for "total" magnitude 1.38E+14 95.00 ... 0.70 0.30 0.34 46 50
[J2000]
4 POSS1 103a-O
1964MCG2..C...0000V
0.60 arcmin 0.40 arcmin ... ... ... ... ... Very high surface brightness 7.40E+14 36.00 ... 0.67 0.33 0.38 48 ...
5 RC3 D_25, R_25 (blue)
1991RC3.9.C...0000d
1.15 log(2a) + 1 ... ... 0.14
log(a/b)
0.15 ... ... 65
[J2000]
25.0 B-mag arcsec^-2^ 6.81E+14 84.80 35.00 0.72 0.28 0.31 44 65
[J2000]
6 RC3 D_0 (blue)
1991RC3.9.C...0000d
1.11 log(2a) + 1 ... ... ... ... ... ... ... 25.0 B-mag arcsec^-2^ 6.81E+14 77.30 ... ... ... ... ... ...
7 r (SDSS Isophotal)
2006SDSS5.C...0000:
54.35 (a) arcsec 32.50 arcsec ... ... ... ... 70.0
[J2000]
25.0 mag arcsec^-2^ 4.77E+14 108.70 ... 0.60 0.40 0.47 53 70
[J2000]
8 r (SDSS Petrosian)
2006SDSS5.C...0000:
7.67 (a) arcsec ... ... ... 0.23 ... ... ... ... 4.77E+14 15.34 0.46 ... ... ... ... ...
9 r (SDSS de Vaucouleurs)
2006SDSS5.C...0000:
5.06 (a) arcsec ... ... 0.686 (b/a) 0.02 ... ... 64.9
[J2000]
... 4.77E+14 10.11 0.04 0.69 0.31 0.36 47 65
[J2000]
10 r (SDSS Exponential)
2006SDSS5.C...0000:
3.56 (a) arcsec ... ... 0.712 (b/a) 0.01 ... ... 62.0
[J2000]
... 4.77E+14 7.12 0.02 0.71 0.29 0.33 45 62
[J2000]


Detailed Information for Each Entry

 No. 1
                                Published Units:                    Homogenized Units:

Reference Code                : 1973UGC...C...0000N
Published Object Name         : UGC 05112                     
Frequency Targeted            : POSS1 103a-O                  
Major Axis (2a)               : 1.40       arcmin                   2a = 84.00 arcsec
Uncertainty                   : ...                                 ... 
Minor Axis (2b)               : 2b =  1.00      arcmin              2b = 60.00 arcsec 
Uncertainty                   : ...                                 ...
Axis Ratio                    : ...                                 b/a = 0.71
Uncertainty                   : ...                                 ...
Ellipticity                   : ...                                 1 - b/a = 0.29
Uncertainty                   : ...                                 ...
Eccentricity                  : ...                                 [(a/b)2-1]/[(a/b)2+1] = 0.32
Uncertainty                   : ...                                 ...
Cos-1(b/a)                    : ...                                 44 deg
Position Angle [Equinox]      :  65    deg [B1950]                  65 deg [J2000]
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          : 093248.         +315600.    (B1950)
Qualifiers                    : From new, raw data
NED Comment                   : Diameters flagged uncertain.            

No. 2 Published Units: Homogenized Units: Reference Code : 20032MASX.C.......: Published Object Name : 2MASX J09354403+3142194 Frequency Targeted : K_s (2MASS isophotal) Major Axis (2a) : a = 31.6 arcsec 2a = 63.20 arcsec Uncertainty : ... ... Minor Axis (2b) : ... 2b = 44.24 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] : 50 deg [J2000] 50 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 : 143.933441 31.705431 (J2000) Qualifiers : From new, raw data NED Comment :
No. 3 Published Units: Homogenized Units: Reference Code : 20032MASX.C.......: Published Object Name : 2MASX J09354403+3142194 Frequency Targeted : K_s (2MASS "total") Major Axis (2a) : a = 47.5 arcsec 2a = 95.00 arcsec Uncertainty : ... ... Minor Axis (2b) : ... 2b = 66.50 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] : 50 deg [J2000] 50 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 : 143.933441 31.705431 (J2000) Qualifiers : From new, raw data NED Comment :
No. 4 Published Units: Homogenized Units: Reference Code : 1964MCG2..C...0000V Published Object Name : MCG +05-23-019 Frequency Targeted : POSS1 103a-O Major Axis (2a) : 0.60 arcmin 2a = 36.00 arcsec Uncertainty : ... ... Minor Axis (2b) : 2b = 0.40 arcmin 2b = 24.00 arcsec Uncertainty : ... ... Axis Ratio : ... b/a = 0.67 Uncertainty : ... ... Ellipticity : ... 1 - b/a = 0.33 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.38 Uncertainty : ... ... Cos-1(b/a) : ... 48 deg Position Angle [Equinox] : ... ... Uncertainty : ... ... Significance : No uncertainty reported Diameter Reference Level : Very 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 : 093248 +3157 (B1950) Qualifiers : From new, raw data NED Comment :
No. 5 Published Units: Homogenized Units: Reference Code : 1991RC3.9.C...0000d Published Object Name : UGC 05112 Frequency Targeted : RC3 D_25, R_25 (blue) Major Axis (2a) : log(2a) + 1 = 1.15 2a = 84.80 arcsec Uncertainty : 0.15 35.00 arcsec Minor Axis (2b) : ... 2b = 61.40 arcsec Uncertainty : ... ... Axis Ratio : log(a/b) = 0.14 b/a = 0.72 Uncertainty : 0.08 0.15 Ellipticity : ... 1 - b/a = 0.28 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.31 Uncertainty : ... ... Cos-1(b/a) : ... 44 deg Position Angle [Equinox] : 65 deg [J2000] 65 deg [J2000] 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 : 093544.5 +314217. (J2000) Qualifiers : Homogenized from previously published data NED Comment :
No. 6 Published Units: Homogenized Units: Reference Code : 1991RC3.9.C...0000d Published Object Name : UGC 05112 Frequency Targeted : RC3 D_0 (blue) Major Axis (2a) : log(2a) + 1 = 1.11 2a = 77.30 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 : 093544.5 +314217. (J2000) Qualifiers : Homogenized from previously published data NED Comment : Extinction and inclination corrected.
No. 7 Published Units: Homogenized Units: Reference Code : 2006SDSS5.C...0000: Published Object Name : SDSS J093544.04+314219.7 Frequency Targeted : r (SDSS Isophotal) Major Axis (2a) : a = 54.35 arcsec 2a = 108.70 arcsec Uncertainty : ... ... Minor Axis (2b) : b = 32.50 arcsec 2b = 65.00 arcsec Uncertainty : ... ... Axis Ratio : ... b/a = 0.60 Uncertainty : ... ... Ellipticity : ... 1 - b/a = 0.40 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.47 Uncertainty : ... ... Cos-1(b/a) : ... 53 deg Position Angle [Equinox] : 70.0 deg [J2000] 70 deg [J2000] Uncertainty : ... ... Significance : No uncertainty reported Diameter Reference Level : 25.0 mag arcsec^-2^ Frequency : 6290 A 4.77E+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 : 143.9335175 31.7054672 (J2000) Qualifiers : From new, raw data; DIA_MAJ or DIA_MIN modified from published data NED Comment :
No. 8 Published Units: Homogenized Units: Reference Code : 2006SDSS5.C...0000: Published Object Name : SDSS J093544.04+314219.7 Frequency Targeted : r (SDSS Petrosian) Major Axis (2a) : a = 7.67 arcsec 2a = 15.34 arcsec Uncertainty : 0.23 arcsec 0.46 arcsec Minor Axis (2b) : ... ... Uncertainty : ... ... Axis Ratio : ... ... Uncertainty : ... ... Ellipticity : ... ... Uncertainty : ... ... Eccentricity : ... ... Uncertainty : ... ... Cos-1(b/a) : ... ... Position Angle [Equinox] : ... ... Uncertainty : ... ... Significance : Based on count statistics only Diameter Reference Level : ... Frequency : 6290 A 4.77E+14 Hz Frequency Mode : Broad-band detector (e.g. photographic plate) Measurement Mode Detector Type : Maps (e.g., 2MASS, VLA, Sloan) Fitting Technique : Profile fitting to image Measured Quantity : See comments Qualifiers : A radius is given in DIA_MAJ, not a diameter Coordinates Targeted : 143.9335175 31.7054672 (J2000) Qualifiers : From new, raw data; DIA_MAJ or DIA_MIN modified from published data NED Comment :
No. 9 Published Units: Homogenized Units: Reference Code : 2006SDSS5.C...0000: Published Object Name : SDSS J093544.04+314219.7 Frequency Targeted : r (SDSS de Vaucouleurs) Major Axis (2a) : a = 5.06 arcsec 2a = 10.11 arcsec Uncertainty : 0.02 arcsec 0.04 arcsec Minor Axis (2b) : ... 2b = 6.94 arcsec Uncertainty : ... 0.00 Axis Ratio : b/a = 0.686 b/a = 0.69 Uncertainty : 0.003 0.00 Ellipticity : ... 1 - b/a = 0.31 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.36 Uncertainty : ... ... Cos-1(b/a) : ... 47 deg Position Angle [Equinox] : 64.9 deg [J2000] 65 deg [J2000] Uncertainty : ... ... Significance : Based on count statistics only Diameter Reference Level : ... Frequency : 6290 A 4.77E+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 : Half-light ("effective") diameter Qualifiers : A radius is given in DIA_MAJ, not a diameter Coordinates Targeted : 143.9335175 31.7054672 (J2000) Qualifiers : From new, raw data; DIA_MAJ or DIA_MIN modified from published data NED Comment : Effective (half-light) radius
No. 10 Published Units: Homogenized Units: Reference Code : 2006SDSS5.C...0000: Published Object Name : SDSS J093544.04+314219.7 Frequency Targeted : r (SDSS Exponential) Major Axis (2a) : a = 3.56 arcsec 2a = 7.12 arcsec Uncertainty : 0.01 arcsec 0.02 arcsec Minor Axis (2b) : ... 2b = 5.07 arcsec Uncertainty : ... 0.00 Axis Ratio : b/a = 0.712 b/a = 0.71 Uncertainty : 0.002 0.00 Ellipticity : ... 1 - b/a = 0.29 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.33 Uncertainty : ... ... Cos-1(b/a) : ... 45 deg Position Angle [Equinox] : 62.0 deg [J2000] 62 deg [J2000] Uncertainty : ... ... Significance : Based on count statistics only Diameter Reference Level : ... Frequency : 6290 A 4.77E+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 : Half-light ("effective") diameter Qualifiers : A radius is given in DIA_MAJ, not a diameter Coordinates Targeted : 143.9335175 31.7054672 (J2000) Qualifiers : From new, raw data; DIA_MAJ or DIA_MIN modified from published data NED Comment : Effective (half-light) radius

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