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Date and Time of the Query: 2019-02-17 T01:19:28 PST
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Diameter data point(s) for object NGC 2988

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
1964MCG2..C...0000V
0.80 arcmin 0.20 arcmin ... ... ... ... ... High surface brightness 7.40E+14 48.00 ... 0.25 0.75 0.88 76 ...
2 r (SDSS Isophotal)
2007SDSS6.C...0000:
1.50 (a) arcsec 1.47 arcsec ... ... ... ... 109.8
[J2000]
25.0 mag arcsec^-2^ 4.77E+14 3.00 ... 0.98 0.02 0.02 11 110
[J2000]
3 r (SDSS Petrosian)
2007SDSS6.C...0000:
0.40 (a) arcsec ... ... ... 0.029 ... ... ... ... 4.77E+14 0.81 0.06 ... ... ... ... ...
4 r (SDSS deVaucouleurs)
2007SDSS6.C...0000:
0.0268 (a) arcsec ... ... 0.270 (b/a) 0.018 ... ... 27.9
[J2000]
... 4.77E+14 0.05 0.04 0.27 0.73 0.86 74 28
[J2000]
5 r (SDSS Exponential)
2007SDSS6.C...0000:
0.0389 (a) arcsec ... ... 0.381 (b/a) 1.015 ... ... 28.0
[J2000]
... 4.77E+14 0.08 2.03 0.38 0.62 0.75 68 28
[J2000]


Detailed Information for Each Entry

 No. 1
                                Published Units:                    Homogenized Units:

Reference Code                : 1964MCG2..C...0000V
Published Object Name         : MCG +04-23-032                
Frequency Targeted            : POSS1 103a-O                  
Major Axis (2a)               : 0.80       arcmin                   2a = 48.00 arcsec
Uncertainty                   : ...                                 ... 
Minor Axis (2b)               : 2b =  0.20      arcmin              2b = 12.00 arcsec 
Uncertainty                   : ...                                 ...
Axis Ratio                    : ...                                 b/a = 0.25
Uncertainty                   : ...                                 ...
Ellipticity                   : ...                                 1 - b/a = 0.75
Uncertainty                   : ...                                 ...
Eccentricity                  : ...                                 [(a/b)2-1]/[(a/b)2+1] = 0.88
Uncertainty                   : ...                                 ...
Cos-1(b/a)                    : ...                                 76 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         : "Outer" diameter
Coordinates Targeted          : 094400          +2213    (B1950)
Qualifiers                    : From new, raw data
NED Comment                   :                                         

No. 2 Published Units: Homogenized Units: Reference Code : 2007SDSS6.C...0000: Published Object Name : SDSS J094647.91+220042.2 Frequency Targeted : r (SDSS Isophotal) Major Axis (2a) : a = 1.50 arcsec 2a = 3.00 arcsec Uncertainty : ... ... Minor Axis (2b) : b = 1.47 arcsec 2b = 2.94 arcsec Uncertainty : ... ... Axis Ratio : ... b/a = 0.98 Uncertainty : ... ... Ellipticity : ... 1 - b/a = 0.02 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.02 Uncertainty : ... ... Cos-1(b/a) : ... 11 deg Position Angle [Equinox] : 109.8 deg [J2000] 110 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 : 146.6996403962 22.0117335807 (J2000) Qualifiers : From new, raw data; DIA_MAJ or DIA_MIN modified from published data NED Comment :
No. 3 Published Units: Homogenized Units: Reference Code : 2007SDSS6.C...0000: Published Object Name : SDSS J094647.91+220042.2 Frequency Targeted : r (SDSS Petrosian) Major Axis (2a) : a = 0.40 arcsec 2a = 0.81 arcsec Uncertainty : 0.029 arcsec 0.06 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 : 146.6996403962 22.0117335807 (J2000) Qualifiers : From new, raw data; DIA_MAJ or DIA_MIN modified from published data NED Comment :
No. 4 Published Units: Homogenized Units: Reference Code : 2007SDSS6.C...0000: Published Object Name : SDSS J094647.91+220042.2 Frequency Targeted : r (SDSS deVaucouleurs) Major Axis (2a) : a = 0.0268 arcsec 2a = 0.05 arcsec Uncertainty : 0.018 arcsec 0.04 arcsec Minor Axis (2b) : ... 2b = 0.01 arcsec Uncertainty : ... 1.36 Axis Ratio : b/a = 0.270 b/a = 0.27 Uncertainty : 36.822 36.82 Ellipticity : ... 1 - b/a = 0.73 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.86 Uncertainty : ... ... Cos-1(b/a) : ... 74 deg Position Angle [Equinox] : 27.9 deg [J2000] 28 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 : 146.6996403962 22.0117335807 (J2000) Qualifiers : From new, raw data; DIA_MAJ or DIA_MIN modified from published data NED Comment : Effective (half-light) radius
No. 5 Published Units: Homogenized Units: Reference Code : 2007SDSS6.C...0000: Published Object Name : SDSS J094647.91+220042.2 Frequency Targeted : r (SDSS Exponential) Major Axis (2a) : a = 0.0389 arcsec 2a = 0.08 arcsec Uncertainty : 1.015 arcsec 2.03 arcsec Minor Axis (2b) : ... 2b = 0.03 arcsec Uncertainty : ... 90.98 Axis Ratio : b/a = 0.381 b/a = 0.38 Uncertainty : 44.794 44.79 Ellipticity : ... 1 - b/a = 0.62 Uncertainty : ... ... Eccentricity : ... [(a/b)2-1]/[(a/b)2+1] = 0.75 Uncertainty : ... ... Cos-1(b/a) : ... 68 deg Position Angle [Equinox] : 28.0 deg [J2000] 28 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 : 146.6996403962 22.0117335807 (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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