Observation by Simon Dawes: My First Variable Star observation - (wa...

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Mr Simon Francis Dawes


Simon Dawes


2020 Apr 04 - 21:00


2020 Apr 09 - 08:36



  • Sky Watcher MN190
  • ZWO ASI 1600 Pro mono
  • Photometric 'R' filter
  • EQ6



Bexleyheath, Kent (S.E. London really), England

Target name



My First Variable Star observation - (was an Exo-Planet)

About this image

Well ok you might debate if an exo-planet is a variable star, but I was taught by Dick Chambers and he said it was an extrinsic variable and those that knew Dick will know he was never wrong.

I promised Roger Pickard I'd observe a variable star this year - here it is Roger.

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Mark Phillips
Mark Phillips, 2020 Apr 09 - 10:10 UTC

More like an eclipsing binary really - with the eclipsing body being a planet. Good observation.

There was some discussion on the ExoClock project as to whether a CMOS sensor could be used instead of a CCD. I think you've just shown it can. Is the 1600 12- or 14-bit? Most CCDs are 16-bit I think.

Mr Simon Francis Dawes
Mr Simon Francis Dawes, 2020 Apr 09 - 13:59 UTC

It is only 12bit but when I compare my results to a friend of mine using a CCD the scatter, range etc. in the results look very similar - if I can get to more sensitive measurements will remain to be seen, but given this is the first 'variable star' I've measured I'd say it was quite promising. I'm very much a beginner in this field. 

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