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Introduction AstrometryDB - New SQLite Database AstroVMA - New Astrometry Section AstroMain - New Astrometry Measurement Section AstroTrigParallax - New Frontend to TrigParallax Tool     Results - Barnards Star	-   -

Introduction

Previously a lot of work was conducted in 2006-2009 period, measuring and analysing the astrometric positions of several Nearby Stars. The work demonstrated that these stars had high proper motion (up to 10 arcsec/year) and had parallax up to 0.6 arcsec. Positions were measured in AstroMain and output to flatfile.  These were then imported into Excel, manually manipulated/QCed and plots created that showed that the stars would either have simple wobbling paths (Barnards Star) or much more complex loci of movement (Ross 248).  In cases of nearby binary stars (like 61 Cygnii), there would be two stars moving on roughly parallel path.   A program called TrigParallax was developed to determine the best 5 parameter solution (RA0,Dec0, PM_RA, PM_Dec, Parallax) that matched each star usinga GA (genetic algorithum) based process.

Barnards Star

    

Ross 248 (HH And)

        

61 Cygni

Since then whilst data has continued to be collected on several stars,  the measurement of astrometric positions and their analysis had been largely set aside due to the tedium of the workflow.

In mid 2026, after developing a Photometry Database and Photometric Data Graphing tool, it was decided to reinvigorate Astrometry Measurement and Analysis, by building a series of new tools and features

•  Astrometry Database   - New SQLite database (replaces flats file and Excel)
•  AstroVMA - New Astrometry Section
•  AstroMain - New Astrometry Section
•  AstroTrigParallax - New frontend to TrigParallax (access original GA based 5 param Astrometry Solution fitting)

Results to date for Barnards star are shown here. 

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AstrometryDB - New SQLite Database

AstrometryDB is a new SQLite database for holding information on

- AstrometrySystem table and supporting tables (AstrometryComponent, AstrometryModel, AstrometryGraph, AstrometryGraphLayer)
   - General details
   - Components & CheckStar details
   - Astrometry Models ('GaiaDR3' and 'Best GA')
   - Graph Configurations

- AstrometryMeasurement table
    - Astrometric Measurements by System, Component, Session (Date) and Image

- AstrometryObservations table
   - Compiled Astrometric Observations by System, Component & Session (Date)

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AstroVMA - New Astrometry Section

AstroVMA program, previously a front end to Photometry Database, has been expanded to include a front end to the Astrometry Database.

New forms constructed for input / editing / viewing of
   Astrometry Systems
     Components
     Models
     Graph Configurations

New forms constructed for viewing
    Astromety Measurements
    Astromety Observations

Astrometry Forms

Astrometry Measurements Form

Astrometry Observations Form

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AstroMain - New Astrometry Measurement Section

AstroMain updated with

New Astrometry Measurement Section.
- Perform Astrometric Measurements on a series of Sessions
- Compile Observatons for each Session
- Results saved to Photometry Database

Extended Graph Plotting capability, specifically for Astrometry Graphs

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AstroTrigParallax - New Frontend to TrigParallax Tool

AstroTrigParallax developed from original TrigParallax Program

New Frontend
- Selection of System, Component and Data
- GA Setup
- Model creation
- Results
- Save to Photometry Database

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Results - Barnards Star

Parameter Model:     GaiaDR3    Best GA  (SE)                Proper Motion RA   (mas/yr)    -801.55    -791.67 +/- 0.0087   Proper Motion Dec   (mas/yr)    10362.39    10426.54   +/- 0.0083   Parallax (mas)     546.976    595.96  +/- 24.05  Distance  ( ly )    5.96    5.47  +/- 0.22    5%-95%    5.96-5.96      5.04 - 5.91

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