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AAVSO Bulletin 79 for 2016 - Stars with Double Maxima

In AAVSO Bulletin 79 there are two stars that exhibit double maxima:  R Cen and R Nor. These stars therefore have primary and secondary maxima and minima. They are not included in the main Bulletin table. Their predicted dates of maximum and minimum for January 2016 through February 2017 are presented here in list form (JD and Gregorian calendar dates) and in approximation of the main Bulletin table format.

V Boo, a semiregular, has intermittently demonstrated double maxima behavior for a number of years. In 2014 it became too irregular to predict maxima and minima accurately and was omitted from AAVSO Bulletin 78. However, in 2015 V Boo became more regular and was not demonstrating double-maxima behavior, so it was returned to Bulletin 79 and is included with the non-double-maxima stars. Observations of V Boo are strongly encouraged, and with an approximate magnitude range of 7-11, it is accessible to many sizes of binoculars and telescopes.

In the information below, 'I' indicates a primary extremum and 'II' a secondary. For example, MAX(I) in the list and MAX(18-I) in the table both mean a primary maximum, in this case on the 18th of the month in which the date appears. Dates are for 2016 except where indicated 2017.

R CEN   P = 512 days   
2457472 MAR 24 min(II)
2457619 AUG 18 MAX(I)
2457778 JAN 24, 2017 min(I)

R NOR   P =  507.5 days
2457508 APR 29 min(II)
2457628 AUG 27 MAX(I)
2457707 NOV 14 min(I)
2457789 FEB 4, 2017 MAX(II)

 

In the table below, the following fields are given:
Name: name of variable star
Links:
 L - to the AAVSO Light Curve Generator
 X - to the International Variable Star Index (VSX)
 T - to the AAVSO table of published maxima/minima of long period variables
R.A. and Declination: coordinates in J2000.0
Period: in days
Range: average visual magnitude range based on data in the AAVSO International Database
N: number of observations in the AAVSO International Database received during calendar year 2015
JAN-DEC-FEB: January-December 2016, January-February 2017

The number in a given month indicates the date of extremum; MAX indicates Maximum and 
min indicates minimum.  The colors indicate (as chosen by the user) the intervals when 
the star will be brighter than visual magnitude 11.0 or fainter than magnitude 13.5.

Bulletin 79 Maxima and Minima for R Cen and R Nor January 2016-February 2017
NAME   L X T R.A.             DECLINATION PERIOD RANGE N JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB
R CEN L X T 14 16 34.32 -59 54 49.3 512 <5.8-11.1> 290 fading fading min(24-II) rising rising rising rising MAX(18-I) fading fading fading fading min(24-I) rising
R NOR L X T 15 35 57.35 -49 30 28.7 507.5 <7.2-13.2> 82 fading fading fading min(29-II) rising rising rising MAX(27-I) fading) fading min(14-I) rising rising MAX(4-II)
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