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LPV Bulletin 2020

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croberrw's picture
LPV Bulletin 2020

Fellow LPV'ers, 

We were able to generate a bulletin for 2020. 

The excel file attached was produced by Eric Dose (DERA) who modified the predictive algorithm his uses for observation planning to replicate the bulletin. 

Eric has also taking things further. From an email he sent me:

"Next, a second demo planned early December will show that this same code will support an online "bulletin" for real-time querying by observers. The user enters ranges for preferred dates and magnitudes, and the system will report either or both of: (1) LPVs with those magnitudes and dates, and/or (2) only LPVs with projected minima or maxima in those same ranges. With the code already in place, this extension will not be hard."

We've been talking to HQ about the online tool. The website is about to undergo some major structural changes, so any implementation would occur after that. I will keep you posted. 

Clear Skies, 

Rich Roberts (RRIA) 

CMJA's picture
LPV Bulletin 2020

This is fantastic! Thanks to everyone that worked on this.


LPV Bulletin 2020

Thank you!


Thank you to everyone that

Thank you to everyone that worked on this.

Steve (TST)

ThomasK's picture
Bulletin for 2019?


What months does the attached Excel-file cover? Looking at a few stars I got the best match for 2019 and not 2020.

Eric Dose
Eric Dose's picture
Let me look at this. It was a

Let me look at this. It was a demonstration document for internal evaluation, and I was surprised to see it released.

ADDED in Edit: Does anyone have an objection to my changing future bulletins' month column headers to "JAN-20", "FEB-20", etc rather than the historical "JAN", "FEB", etc? This would identify the applicable year within the document itself, rather than from its filename only.

Eric Dose
Eric Dose's picture
Let's take one step back, for now

ThomasK: Thank you! As we say in the States, "Good catch".

LPV Observers: Please do not use the bulletin at the top of this forum if the link is still there.

In November I sent this as a 2019 Bulletin test/demo file built from 2015-2018 observation data. But somewhere and sometime since it apparently got relabeled as a 2020 Bulletin, which it is not.

So let's take one temporary step back. My next plans are to:

(1) Generate a bona fide 2020 Bulletin, with (for clarity) column headers like "Jan2020" etc in place of the old "JAN" style, right in the document itself.

(2) Then query AAVSO leadership for any changes they would like to make, whether formatting or technical.

(3) Once these changes are made, I will want to follow their preferences on publication of the new Bulletin.

Everyone: does this seem reasonable? Absent objections, I will start this work this weekend. Needed software changes should be few, and I would expect to complete the above item (1) within a week.

Eric Dose (DERA)

hambsch's picture
No objections, update of pyclg?

Hi Eric,

no objections on your planned improvements to the bulletin. I am not really a user of it. I wantd to take this opportunity to ask about whether you did updates to your pyclg light curve generator which I heavily use. If so please point me again to the link where to download the newest version.

Maybe you remember that I mentioned a bug to you in case when you uncheck plot in JD then the error bars disappear.

Thanks, Josch

croberrw's picture
I took down the original file

I took down the original file. I apologize for releasing the wrong file and causing this confusion. I'll repost when we have the correct bulletin. 

Clear Skies, 

Rich Roberts (RRIA)

Eric Dose
Eric Dose's picture
(1) Bulletin render (2) pylcg tweak

Robert: Thanks. It shouldn't take long at all.

Josch: I remember that you had mentioned something, but I lost the detail. So thanks for the reminder; it's now on my to-do list right behind the Bulletin.

LPV Bulletin 2020?

Dear RRIA and DERA,

Wher can I find the Excel-file?



Eric Dose
Eric Dose's picture
Not ready yet (Jan 13 2020)

The 2020 Bulletin is not ready yet; it is awaiting comments from AAVSO headquarters, and then I will have to run the software to generate it.

When the Bulletin is ready, a link will be posted in this forum thread. It will be in CSV (comma-separated values) format, which can be opened directly by Excel.

HTY's picture
Thank You!

Eric and Rich,

Thank you so much for this.  REALLY looking forward to the return of the bulletin.


BTB's picture
Another option

In the meantime I invite you to try my version of the bulleting available from

Ed Wiley_WEY
Ed Wiley_WEY's picture
Another Option


Just downloaded and tried "another option" Very nice. I especially like the "within 30 days of max" feature. I am exploring CMOS photometry of bright variables and predicting targets likely to be within 30 days of maximum at a certain data simplifies planning.


vega82's picture


Good afternoon. Tell me if Bulletin 2020 appeared?

Eric Dose
Eric Dose's picture
Not yet.

Not yet. I sent it to AAVSO but have not heard back. At this point I suppose my best course is to regenerate it and then post a link to it here, but it will be unapproved by AAVSO. On delivery I will do the best I can, but I am utterly buried in astronomy projects just now.

vega82's picture
Hello, is there any news?

Hello, is there any news?

Eric Dose
Eric Dose's picture
LPV Bulletin coming up

Hi, all,

After a crazy winter for me (and now a crazy spring for everyone), the LPV bulletin has percolated to the top of my list, and the first 2020 advanced draft should come out this weekend. I'll plan to post it in this thread.

Format will be close to that of years past, except that the month-column headers have been improved from "JAN", "FEB" etc to "Jan 20" "Feb 21" (meaning 2020 and 2021) to ensure at a glance that the correct year is in play. It will be a CSV file with semi-colon delimiters, importable directly into Excel, OpenOffice, etc.

Let me know if you have preferences for other change from the Bulletins of years past. Specifically:

  • The Bulletins could come out annually as was done in the past...but every 6 months might be better, each issue covering the next 8-10 months. This has two advantages: (1) the copy you're using on any given night will be based on more recent data thus better, and (2) the spreadsheets will be smaller. Predictions for 13-14 months in the future are not great anyway. I'll plan to cover March-December 2020 in this first issue unless there is a consensus otherwise.
  • My first offering will add the predicted V magnitude to each min or max. I've heard some difference of opinion on this: some visual observers like to "not be influenced", but CCD observers have to set exposure times. I don't really care. Let me know, it's easy to do either way.

 In any case, this first draft will be as good as I can make it, but I'll certainly be open to change suggestions.

CMJA's picture
Re: LPV Bulletin coming up

Hello Eric,

Thanks so much for keeping your nose to the grindstone toward keeping the Bulletin alive and improving its info.

I like all the suggestions you make, and support whatever it takes to make the Bulletin easier for you and HQ staff to update and publish. As for the V mags, I like the idea of publishing the values for the reasons you state. Visual observers can just ignore the values (like they should ignore recent observations in Web Obs and LCG) or delete the values.

Kindest Regards, Stay Safe, and Good Observing,


Eric Dose
Eric Dose's picture
LPV Bulletin 2020-03 posted here

The new LPV Bulletin 2020-03 is attached here, covering the period March-December 2020. There are two versions, one CSV file with magnitudes for each Min and Max, and another without. They are otherwise identical.

These Min and Max predictions are based on AID data in V, Visual, and TG for 5 LPV periods through March 15 2020. The N(obs) observation counts are for the 12 months March 1 2019 through Feb 29 2020. 

For the curious: the python code used is version 1.01, available on my Github repo at . I will summarize computational methods on the repo's README file, within 2-3 days from now.

When you use this, realize that the predictions are (necessarily) made from past data. I don't suggest that they are perfect (indeed, if mags were perfectly predictable we wouldn't need observations!). Variable stars vary, and they vary in their variation. I only suggest that the predictions are at least as good as, and probably much better than, one could make by inspecting any number of lightcurve plots, especially for stars having very few recent observations.

I think this is what people are looking for. Let me know if not, or if you have suggestions for improvement. We'll do this again in a few months' time.

Eric Dose, DERA

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