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EP Observing Planning

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clkotnik's picture
EP Observing Planning

I am putting together a little planning tool for myself and wondered if it might appeal to other EP observers.  I know if seems odd there should be "yet another planning tool".  

I want something like the ETD transit prediction tool,  I find the transit begin, center and end times along with my local altitude very helpful in deciding where to observe a particual EP.  However, rather than all the dates for a given EP I want all the EPs for a given date.  That way I can zero in on a few targets and research them further.

Attached is what I have so far.  While it looks a bit awkward to have such a long graphic, this runs in a Jupyter notebook so I just scroll up and down with the browser.

Let me know if you might have use for this.


best regards,


File Upload: 
wglogowski's picture
EP Observing Planning


I think this is a great idea.  I now have to navigate to the NASA Exoplanet Archive, populate a list then sort at least three ways (RA/Dec), Period, Midpoint time.  It would be great to be able to sort automatically.


gbkinne's picture
EP Observing Planning

I too would appreciate this tool.  I'm just getting my new system setup now and calibrating, getting ready hopefully do some good photometry. 


B.P.Vietje's picture
EP Observing Planner

This looks like a real nice tool, Clif.  I've been using the ETD from the Czech Astro. Soc., which works well for "what transits are available tonight", but now I'd like to make repeat observations of what appear to be the mose interesting targets.  I like all the color coding, too!


Clear skies,


Brad Vietje

Newbury, VT

Eric Dose
Eric Dose's picture
You're welcome to use any and

You're welcome to use any and all code snippets from the planning tool I wrote last year, which I now use every night for my program covering ~ 200 Miras and ~ 80 eclipsers. For Miras on a given observing night, it projects times of sky availability, and magnitudes and exposure times in several filters, and sorts by transit time. The trick for very-high-amplitude variable stars like Miras is to get the exposure times even close to right. And similarly for eclipsers and Landolt standard fields, different math of course. Once the code has compiled all this in a night-roster spreadsheet, one line of relevant data per available target, I simply drag-and-drop desired target names from there over into a planning spreadsheet. Then, the code reads the planning spreadsheet and automatically generates (1) a summary for me, and (2) fully compliant ACP scripts for my remote scope. I simply rearrange the planning spreadsheet until the summary looks just the way I want it, and then upload the ACP scripts to my remote scope, which then hits 50-100 targets in 2-3 filters without any intervention.

Not sure this squarely addresses your plans, but as it's already working I'd be remiss not to mention it. I gave a poster on this strategy at the joint SAS/AAVSO meeting, June 2017. The code is pretty involved (several thousand lines, all unit-tested), admittedly not user-friendly (unless I'm the user, I suppose). Still, you may find a use for parts of the computing engine, whose code and test code are available publicly at

clkotnik's picture
I'll take a look

Thanks Eric.  I'll take a look.




pablotwa's picture
EP Observing Planning

I would also be very interested in that tool Cliff, thanks!

HBB's picture
EP Observing Tool


That looks very useful.  I would be interested in using it.


PVEA's picture
EP Observing Tool

Interesting tool but you can also use "ETD transit prediction"  where you will get all EP for particular night for your location.

For my location the result is quite informative:



WBY's picture
EP Observing Tool

Similar to Velimir, but I use the NASA Exoplanet Archive Transit Service T.tool at

I created a file of Transiting Exoplanets using a download NASA website of transiting exoplanets using an Excel spreadsheet That fit a set of Criteria appropriate for my equipment and locations. My criteria for my location at approx 29 N Lat and 10" aperture telescope were transit depth >0.9, St_mag or V_mag <13.0 and north of -11 Dec. The dec limitation is simply to weed out those host stars that are unlikely to be above something approaching airmass 2.0 for a a complete transit plus at least a half hour OOT on each end. My input file, the query form and an output 18:00 today to 05:00 tomorrow. You can select which columns of output info you want to include in the display and download, the period of time you want to cover and the format of the download file. I only did one night in this example. I usually do them for a week in advance for planning purposes, but you can pick any period (haven't tried periods in the past) up to the maximum permitted number of days. This works well for me and took only took a couple of hours to set up the list for my site. only have to do once and then you can just add any new discoveries that meet your criteria. It took me about 5 minutes to run this search including opening my browser and accessing the website. NASA has provided a darned good ephemeris and observation planning tool out of the box. I would check it out before doing a lot of programming, unless, of course, you enjoy programming. 

Brad Walter, WBY


clkotnik's picture
Very Interesting

I find this discussion interesting.  There certainly are a lot of interesting ways to plan for periodic variable observation.  The EB community has a number.  I have worked with Pierre de Ponthiere's planner.  The ones available from ETD and NASA look useful.  Of course Eric's automated workflow is a whole other realm.

I guess I got started on this because I worked with the new AAVSO Target Tool, wanting to support the campaigns there.  I was a bit disappointed in how it handles periodic variables.  I realize that there are some good reasons why it works the way it does.  Still I wanted to get an idea where the variables listed were in their cycle without jumping to another page.

And yes, I do find software development enjoyable.  I starting working with this Python, Jupyter environment and find it suits my current situation.  I think perhaps all the discussion of Jupyter in Nashville got me thinking a lot of folks were also using it.  That is perhaps not the case.  It is also a bit different from a standard PC app - sort of like giving someone a spreadsheet where they see all the formula.  I look forward to seeing what the LSST folks do with Jupyter notebooks.

So I created this little program so that it could read the export file from the AAVSO Target Tool and then enhanced it to also do EPs.  From Eric's comments on Miras and the small amount I know of EBs, it seems each class of periodic variable will have its own special requirements.


Thanks all for the discuss,



wglogowski's picture
What I like about the ETD tool

I have also been following the discussion and I have used and still use the NASA Exoplanet Archive tool but what I like about ETD is its graphical nature.  I have been working on a phyton tool that will extract the NASA Exoplanet Archive data and then feed it into Cliff's ETD application.  I'll post an update soon.


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