Introduction

The double star KUI82AB,C separation (rho) and position angle (theta) were measured on five Canon DSLR images 5970, 5971, 5972, 5973 and 5974 with AIP4WIN V2.4.8B software running on an Apple MacBook Pro running a virtual machine with Microsoft Windows 7. The images were taken buy Tom Frey using his alt-azimuth Dob and DSLR.

Below is the double star KUI82AB,C separation (rho = 50.119 arcseconds) and position angle (theta = 313.753 for J2000) based on the mean RA and Dec of the AIP4WIN measurements. The rho and theta measurements have not been precessed to the observation date of May 30, 2013.

The below plots are equirectangular map projections of the sky on a flat plot. The plots have been adjusted so that RA distance is equal to the Dec distance. As a result a circle of fixed radii will be round and not distorted by the map projection.

Below is a plot of the five images (5970, 5971, 5972, 5973 and 5974) KUI 82 AB RA and Dec positions based on the individual RA and Dec measurements. The average of the RA and Dec is in the center of the plot and is called primary average. All five RA and Dec measurements were within about 0.4 arcseconds radius of the RA and Dec average.

Below is a plot of the five images (5970, 5971, 5972, 5973 and 5974) KUI 82 C RA and Dec positions based on the individual RA and Dec measurements. The average of the RA and Dec is in the center of the plot and is called secondary average. All five RA and Dec measurements were within about 0.4 arcseconds radius of the RA and Dec average.

Below is a data analysis output KUI82_20130927_192842_DataOut.txt file created by the Python script DoubleStarsAnalysisV22.py.zip with the KUI82_AIP4WIN_Data_In.txt file.
The Python script was created by David Haworth to calculate and plot the the separation (rho) and position angle (theta) of double stars given the double stars RA and Dec in a CSV txt file. The Python script was developed with the free Python Canopy Express programming environment. David uses Canopy Express on computers with the Mac OS X and Windows 7 operating systems. Canopy Express simplifies using Python because it installs and manages the updates to over 30 preconfigured Python packages.

Date: 2013-09-27 time: 19:28
Python script file name: DoubleStarsAnalysisV22.py

Data file: KUI82_AIP4WIN_Data_In.txt has 5 rows
Data file contains:

Row 0:KUI 82, 5-30-2013, 9:46:46, Image, 5970, Primary RA, 17, 29, 19.88, Dec, 29, 23, 27.5, Secondary RA, 17, 29, 17.12, Dec, 29, 24, 2.0, P Label XY offset, 0,  0.6, S Label XY offset, 0, 0.6, Plot Size, 1.3, Circles, 3, .5, AIP4WIN Plate Solve for RA & Dec
Row 1:KUI 82, 5-30-2013, 9:51:33, Image, 5971, Primary RA, 17, 29, 19.90, Dec, 29, 23, 27.4, Secondary RA, 17, 29, 17.12, Dec, 29, 24, 2.2, P Label XY offset, 0,  0.6, S Label XY offset, 0, 0.6, Plot Size, 1.3, Circles, 3, .5, AIP4WIN Plate Solve for RA & Dec
Row 2:KUI 82, 5-30-2013, 9:51:43, Image, 5972, Primary RA, 17, 29, 19.93, Dec, 29, 23, 27.1, Secondary RA, 17, 29, 17.14, Dec, 29, 24, 1.9, P Label XY offset, 0,  0.6, S Label XY offset, 0, 0.6, Plot Size, 1.3, Circles, 3, .5, AIP4WIN Plate Solve for RA & Dec
Row 3:KUI 82, 5-30-2013, 9:46:46, Image, 5973, Primary RA, 17, 29, 19.91, Dec, 29, 23, 27.1, Secondary RA, 17, 29, 17.16, Dec, 29, 24, 1.7, P Label XY offset, 0,  0.6, S Label XY offset, 0, 0.6, Plot Size, 1.3, Circles, 3, .5, AIP4WIN Plate Solve for RA & Dec
Row 4:KUI 82, 5-30-2013, 9:55:31, Image, 5974, Primary RA, 17, 29, 19.88, Dec, 29, 23, 27.1, Secondary RA, 17, 29, 17.11, Dec, 29, 24, 1.7, P Label XY offset, 0,  0.6, S Label XY offset, 0, 0.6, Plot Size, 1.3, Circles, 3, .2, AIP4WIN Plate Solve for RA & Dec

Double star name:KUI 82
Comment: AIP4WIN Plate Solve for RA & Dec

Image 5970.0 analysis:
   Primary RA = 17h 29' 19.88"
   Primary RA = 262.33283 degrees
   Primary Dec = 29 degrees 23' 27.5"
   Primary Dec = 29.39097 degrees
   Secondary RA = 17h 29' 17.12"
   Secondary RA = 262.32133 degrees
   Secondary Dec = 29 degrees 24' 2.0"
   Secondary Dec = 29.40056 degrees
   Rho = 49.91392 arcseconds, theta = 313.72437 degrees

Image 5971.0 analysis:
   Primary RA = 17h 29' 19.9"
   Primary RA = 262.33292 degrees
   Primary Dec = 29 degrees 23' 27.4"
   Primary Dec = 29.39094 degrees
   Secondary RA = 17h 29' 17.12"
   Secondary RA = 262.32133 degrees
   Secondary Dec = 29 degrees 24' 2.2"
   Secondary Dec = 29.40061 degrees
   Rho = 50.31020 arcseconds, theta = 313.76552 degrees

Image 5972.0 analysis:
   Primary RA = 17h 29' 19.93"
   Primary RA = 262.33304 degrees
   Primary Dec = 29 degrees 23' 27.1"
   Primary Dec = 29.39086 degrees
   Secondary RA = 17h 29' 17.14"
   Secondary RA = 262.32142 degrees
   Secondary Dec = 29 degrees 24' 1.9"
   Secondary Dec = 29.40053 degrees
   Rho = 50.40468 arcseconds, theta = 313.66273 degrees

Image 5973.0 analysis:
   Primary RA = 17h 29' 19.91"
   Primary RA = 262.33296 degrees
   Primary Dec = 29 degrees 23' 27.1"
   Primary Dec = 29.39086 degrees
   Secondary RA = 17h 29' 17.16"
   Secondary RA = 262.32150 degrees
   Secondary Dec = 29 degrees 24' 1.7"
   Secondary Dec = 29.40047 degrees
   Rho = 49.88889 arcseconds, theta = 313.91109 degrees

Image 5974.0 analysis:
   Primary RA = 17h 29' 19.88"
   Primary RA = 262.33283 degrees
   Primary Dec = 29 degrees 23' 27.1"
   Primary Dec = 29.39086 degrees
   Secondary RA = 17h 29' 17.11"
   Secondary RA = 262.32129 degrees
   Secondary Dec = 29 degrees 24' 1.7"
   Secondary Dec = 29.40047 degrees
   Rho = 50.07752 arcseconds, theta = 313.70367 degrees

5 Rho & theta measurements analysis:
   Image 5970, rho = 49.91392 arcseconds, theta = 313.72437 degrees
   Image 5971, rho = 50.31020 arcseconds, theta = 313.76552 degrees
   Image 5972, rho = 50.40468 arcseconds, theta = 313.66273 degrees
   Image 5973, rho = 49.88889 arcseconds, theta = 313.91109 degrees
   Image 5974, rho = 50.07752 arcseconds, theta = 313.70367 degrees

   Rho mean = 50.11904 arcseconds
   Rho standard deviation = 0.20732 arcseconds
   Rho standard error of the mean = 0.09271 arcseconds
   Rho mean - standard deviation = 49.91173 arcseconds
   Rho mean + standard deviation = 50.32636 arcseconds
   Maximum rho = 50.40468 arcseconds in image 5972.0
   Minimum rho = 49.88889 arcseconds in image 5973.0
   Rho spread = 0.51580 arcseconds, rho spread percentage of rho mean 1.03%

   Theta mean = 313.75348 degrees
   Theta standard deviation = 0.08550 degrees
   Theta standard error of the mean = 0.03823 arcseconds
   Theta mean - standard deviation = 313.66798 degrees
   Theta mean + standard deviation = 313.83897 degrees
   Maximum theta  = 313.91109 degrees in image 5973.0
   Minimum theta  = 313.66273 degrees in image 5972.0
   Theta spread = 0.24835 degrees
   Theta spread  = 14.90121 arcminutes
   Theta spread  = 894.07273 arcseconds

Mean of 5 images RA & Dec analysis:
   Mean of primary RA & Dec:
      RA mean = 262.33292 degrees
      RA standard deviation = 0.0000791 degrees, 0.0047434 arcminutes, 0.2846050 arcseconds
      RA standard error of the mean = 0.0000354 degrees, 0.0021213 arcminutes, 0.1272792 arcseconds
      Dec = 29.39090 degrees
      Dec standard deviation = 0.0000484 degrees, 0.0029059 arcminutes, 0.1743560 arcseconds
      Dec standard error of the mean = 0.0000217 degrees, 0.0012996 arcminutes, 0.0779744 arcseconds
   Mean of secondary RA & Dec:
      RA = 262.32137 degrees
      RA standard deviation = 0.0000745 degrees, 0.0044721 arcminutes, 0.2683282 arcseconds
      RA standard error of the mean = 0.0000333 degrees, 0.0020000 arcminutes, 0.1200000 arcseconds
      Dec = 29.40053 degrees
      Dec standard deviation = 0.0000527 degrees, 0.0029059 arcminutes, 0.1743560 arcseconds
      Dec standard error of the mean = 0.0000236 degrees, 0.0014142 arcminutes, 0.0848528 arcseconds
   Rho = 50.11899 arcseconds, theta = 313.75327 degrees
Plot 3 circles in radii increments of 0.20 arcseconds.

Double star AB plot size is 132.30 by 115.27 arcseconds.
Primary plot size is 1.49 by 1.30 arcseconds.
Secondary plot size is 1.49 by 1.30 arcseconds.
Equal angular adjustment of plot RA is True.

End of data analysis.

Links

• Double Star Measurements with an Alt-azimuth Dob and DSLR
• Alt-azimuth Dob and DSLR Equipment Used in Double Star Measurements
• Double Star Separation (Rho) and Position Angle (Theta) Measurements
• Double Star Measurements with AIP4WIN
• Opening a DSLR Raw Image with AIP4WIN
• Astrometric Measurements with AIP4WIN
• Star Quality Measurements with AIP4WIN
• Double Star KUI82ABC
• Double Star KUI82AB,C Analysis with AIP4WIN
• Double Star KUI82AB,C Analysis with Astrometrica
• Alt-Azimuth Field Rotation

References

• AIP4WIN
• Python

Thomas G. Frey Thomas G. Frey is Professor Emeritus of Chemistry at California Polytechnic State University, San Luis Obispo, CA. He has been an active member of the Central Coast Astronomical Society for over 25 years. He was a team leader at the Pine Mountain Observatory (PMO) Summer Science Research Work- shop, Bend, OR, 2009 and co-director of the PMO workshop, summer of 2011.

David Haworth David Haworth enjoys astronomy imaging and processing those images to bring out details that cannot be seen easily by visual observing with the same size optics. David Haworth started astroimaging with a Cookbook CCD camera he built in 1996 and since then has used many types of cameras to image the sky. David wrote Chapter 2: "Afocal Photography with Digital Cameras" in the second edition of "The Art and Science of CCD Astronomy" which was published in December 2005. David's images have appeared in magazine front covers, articles, books, catalogs, videos, music CD covers, T-shirts, other web sites, etc.

© 1998-2013 David Haworth