PMDSA

Photometric Method for Double Star Analysis

BACKGROUND

This code is used to analyze basic information of binary star systems. Please note that there are some bugs in this code, that can make some values be very far off, but the median and mean values are generally within ()% of the accepted values. The code as is, provides the system's Seperation (Arcseconds), Position Angle (degrees), and Difference in Magnitude (Delta Mag)

USE

The code was built for performance on Python3.13, though some backwards compatability likely exists up to a certain point.

Requirements

pip install numpy

OR

pip install -r requirements.txt

Bash/cmd

python3 PMDSA.py /path/to/file.fits

or gui with

python3 gui.py

If you don't have your target centered in your images, I suggest adding the RA and DEC (in degrees) in the gui or to the python command like

python3 PMDSA.py /path/to/file.fits deg_RA deg_DEC

To batch run this program use run.sh in bash

./run.sh /path/to/fits/directory [deg_RA] [deg_DEC]

or run.bat for cmd

./run.bat /path/to/fits/directory [deg_RA] [deg_DEC]

These shell scripts write the outputs to CSV and can handle multiple targets in different subdirectories if needed.

NOTES

Images must be plate-solved with WCS values available in the FITS header. My recommendation is to use astrometry.net

The output of the function is in a CSV format in the order Seperation,PositionAngle, Delta Magnitude

Acknowledgments:

Special Thanks to Numpy and Matplotlib

The writing of this code was tested using data provided in the NSF's Four Corners Student Research Consortium funded by NSF grant NSF#2428684 and data from Dimension Point observatory.

Citations:

If you use this code for the analysis of your code, please include the following insert as an acknowledgment and please reach out to me so we can show your published work here.

Analysis used in this publication was assissted in whole or part by PMDSA provided by HarbingerOfFire on github (https://github.com/harbingeroffire/PMDSA)

Past works include:

Syfrett, Malachi, et al. View of Comparative Analysis of Two Astrometric Measuring Methods on Five Known Binaries. Journal of Double Star Observations, 13 July, 2025, doublestarsjournal.org/index.php/jdso/article/view/89/32.