Vereniging Voor Sterrenkunde, Werkgroep Veranderlijke Sterren (Belgium) (VVS)
Sat, 02/22/2014 - 11:43

Help, it's almost march...! When can we excpect the new predictions for Mira stars? I use them a lot in the field with my "Mira-charts-for-binoculars binder". A very handy tool!

Coming next week...

Hi Bruno,

We're always happy to hear people want the Bulletin! Elizabeth Waagen has already gotten private emails about it too, and we appreciate the interest.  It's on the way -- the infrastructure for serving the tables online is already tested and in place and once the last few dozen stars are measured and the results checked, it will go live.

The current bulletin (Bulletin 76) runs through the end of February 2014, and we typically publish the bulletin after mid-February each year.  It will definitely be by February 28, but we are aiming for publication of Bulletin 77 a few days prior.

Clear skies,


American Association of Variable Star Observers (AAVSO)
Bulletin 77 published and online

AAVSO Bulletin 77: Predicted Dates of Maxima and Minima of Long Period Variables for 2014 has been published and is available online via the above link.

There are several versions available: formatted .pdf file for downloading, comma-separated .csv file for spreadsheets, and an interactive Bulletin Generator that allows you to customize your Bulletin. Don't forget the separate file of predicted dates for the three double-maxima stars V Boo, R Cen, and R Nor.

Using the Bulletin to plan your observing program can really help make the most of your precious time at the telescope! If you are a regular user of the Bulletin, you know what I mean. If you have never tried using the Bulletin, give it a go.

Good observing!

Elizabeth Waagen, AAVSO HQ

American Association of Variable Star Observers (AAVSO)
obscure miras

Hi Elizabeth,

Just downloaded the 'stars in need' file, and was surprised to find many 'old friends' there (Y Cas, TY Cyg etc). I now have four folders to use at the eyepiece! One for constellations A-C, one for D-V, one for 'out of season' stars, and now another for 'Miras in need' - so what happens to the even more underobserved stars - or I guess they ARE less observed, purely from being more 'obscure' - objects such as (off the top of my head) HT Aur, CM Cyg etc. Does their (presumed) obscurity make them even more worthy of observation than those on the 'Miras in need' list?

American Association of Variable Star Observers (AAVSO)
prioritizing Miras

Hi Michael,

Excellent question! The frustrating thing is that there are so many stars needing coverage and only so much time. We gave top priority to the LPVs in the current AAVSO Bulletin because they have mean curves and long-existing light curves, and continuing good coverage is needed to protect and reninforce their potential as stellar evolution study candidates. That said, many of the former Bulletin stars also had pretty good coverage and would benefit from continued coverage. Also, who is to say that some of the woefully underobserved or completely unobserved LPVs might not be extremely interesting?

I think the needy current Bulletin stars really do need to have top priority. If you have additional time, pick up some of the former Bulletin stars with a reasonable amount of data, and maybe include one or two pitiful or completely new ones (to provide the fundamental information on them). If you have favorites, by all means include them regardless of what category they are in.

Two key things are:

1) Utilize your observing power effectively. If you have a large telescope, don't observe Mira itself - the observers with binoculars and smaller scopes have it covered from max through min and back again. Go after the fainter LPVs and/or the minimum end of the light curves of brighter ones. Conversely, if you have binocs or a small scope, don't go after khi Cyg at minimum - there will be other observers looking at it who can see it and your time would be better spent making a positive observation of a star you can see rather than a fainter-than. VStar and the Light Curve Generator are great aids for deciding about each star.

2) Stick with the stars you have chosen. They'll become old friends! Follow them every year for continuity's sake. It is difficult to assess one or two observations of a star, especially if there are not many observations from other observers to provide context. Regularly-made observations made year after year by an observer are a great gift.

Long answer - sorry! Clearly a topic close to my heart :)

Good observing,