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Finding maxima predictions for Mira variables

Predictions for upcoming maxima of Mira type variables can be found in several locations. Three of these are listed below.

Do bear in mind however, that the intervals between maxima are not fixed in size and the catalogued periods of Mira type variables are only the average intervals between maxima. Maxima may, on occasion, occur 2-3 weeks earlier than predicted or 2-3 weeks later.

In addition, the peak brightness differs from one cycle to the next. Most predictions specify the average brightness range, but a few specify the extreme brightness range. Many maxima will peak half a magnitude or more short of the extreme upper limits.

 

SPA VSS programme stars

Predictions for upcoming maxima of Mira type variables on the SPA VSS programme can be found in the Sky Diary section of the bi-monthly magazine Popular Astronomy.

and on-line at

http://www.popastro.com/skydiary/index.php

 

BAA VSS programme stars

Predictions for these stars can be found in the BAA Handbook

and on-line at

http://www.britastro.org/vss/mira_predictions.htm

As can be seen in this 2016 listing, these predictions only give a rough guide to the date on which each maximum might occur, illustrating the uncertainty that exists in all predictions for Mira type variables. Other than for those stars marked with an asterisk, the magnitude ranges quoted are average ranges.

 

Predictions from the AAVSO

The AAVSO publishes a list of predictions each year for upcoming maxima and minima of a large number of Mira type variables. This is usually published as an AAVSO bulletin. The 2016 listing, published in late February,  and covering 14 months, can be found at https://www.aavso.org/aavso-bulletin-79-2016

Once again, remember that the dates quoted in the listing are only approximate and the actual maxima may occur somewhat earlier or later than these dates.

The bulletin can be downloaded as a PDF file or as a CSV file. The stars are listed in order of Right Ascension. You may find it more convenient to download it as a CSV file and then sort it alphabetically, as is shown below for the 2016 listing:

The magnitude ranges shown above are average ranges.