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RX And - CV period ?

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Tim Haymes's picture
Last seen: 2 hours 19 min ago
Joined: 13/06/2014 - 21:53
RX And - CV period ?

I am looking for a variable with a period i can measure in 1 night by imaging and use of Astro Image J.  In my search on the AAVSO i found RX And.   On the Target tool the period is given as 0.209893 days, but when plotting past observations the period is 25 days.   So what is the 0.2098 day period, and can i measure this ?

Are there any other candidates ?  -  thankyou.

sjbean's picture
Last seen: 1 week 6 days ago
Joined: 09/03/2019 - 16:30
TESS measurements

Tim, At the MAST site there is one 27 day photometry measurement for RX And in the TESS data. this record suggests there may be a period of 0.21 days. However there seems to be a lot of short term variation that makes pulling out the 0.21 period really difficult.

MAST is at STScI | Mikulski Archive for Space Telescopes (MAST) Portal

type in "rx and"  into the "and enter target" box and hit RETURN. Click on the uppermost "Timeseries Viewer" icon in the second row down. Up pops the photometry record which you can zoom into.


garypoyner's picture
Last seen: 6 hours 40 min ago
Joined: 04/03/2014 - 15:40
RX And


This is the orbital period (Porb) of the system.


Jeremy's picture
Last seen: 33 min 1 sec ago
Joined: 04/03/2014 - 22:00
Tim, the Variable Star

Tim, the Variable Star Section CCD Target List has some shorter period eclipsing binaries that might be useful if your aim is to test your system. The Beginner’s Category has a few systems that are 1 day or less. Ones around atm include EG Cep and TZ Lyr.

Given the short nights atm, you would need very short periods. 

You could also look at any SU UMa dwarf novae that are in outburst. CVnet lists current ones.  V1227 Her (UGSU, eclipsing, orbital period 0.064419 d  (92.763 min)) might be a good one for you. There is a Journal paper on it here

Tim Haymes's picture
Last seen: 2 hours 19 min ago
Joined: 13/06/2014 - 21:53
Interesting suggestions

Thank you Gentlemen for your suggestions and further reading !  Very interesting...