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Applicabilty of aavso variable star photometry guide to exoplanet detection

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Applicabilty of aavso variable star photometry guide to exoplanet detection


I am new to photometry, even to astrophotography, but would like to get started on exoplanet detection.

Before I get too deep into reading the aavso variable star photometry guide, can I ask if that is indeed the right way to go to learn about exoplanet photometry? Or are there significant differences?



FJQ's picture
Applicabilty of aavso variable star photometry guide to exoplane

To:  Ike,

Welcome to AASVO!  I think reading through the ccd-photometry-guide and then the Exoplanet oberserving guide are your best choices to getting a grasp at doing high accuracy, quick cadence exoplanet photometry.  After you get a a rigid mount, CCD/SLR, photometric filters and optical system and you can guide images well focused and not trailed, you can seriously consider any kind of photometry.   I myself use a C-11 with an F/6.3 reducer, Astrodon I,R,V,B, and Clear filters with an SBIG ST-8xme with RGB on a 100mm optic (ontop of the C-11) on an iOptron CEM60 mount.

I dont do much exoplanet oberving because this usually involves shooting a star that comes near mid-eclipse at meridian at your location.  This requires alot of preperation in selecting applicable stars that are high up in altitude (low altitude exoplanter observation are almost impossible do to scintillation in the atmosphere) and since these events last 2-6 hours, not including the fact you need to monitor at least 1-2 hours befor and after eclipse!  If you have many obstacles and buildings blocking large portions of the sky (like I do) your chances of getting pre, mid-eclipse, and post eclispe measurements is nil.  Variable stars usually dont have this problem as were watching slower trends in brightness over many days if not months.

If I was starting over or just beginning, I would observe popular and bright (6-10 magnitude) variable stars with  IRVB filters (see WebObs Search) that many experianced people observe and report here and compare the magnitudes my system is getting to the averge magnitudes other oberves are getting.  Photometry takes serveral months to master and if you want to provide results the professional astronomers would use, its best to determine your system's Transform Coefficients to help convert your data standard magnitudes. See Chapter 6 of the CCD Observer guide: Getting a yearly AASVO membership gains you access to VPHOT which you can use to upload your data from a standard cluster and determin you transform coefficients and get standard IRVBU magnitudes using Transform Generator (TG), and TransformApplier (TA); see Variable star photometry encompasses so many objects besided exoplanets, that you will never be at a loss for targets the professional need data for!


Thank you James. I guess

Thank you James. I guess there is more to this than I realised - and a longer learning curve. I had better get reading and then come back to the forum with the many questions I am sure to have !

Thanks again


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