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Observing Programme 2015 onwards

Variable Star section members are, of course, free to observe and submit observations of any variable star.

The "programme" which follows has been designed, however, with beginners in mind and lists stars that are (hopefully!) not too difficult to locate and which usually show a good amount of variation.

Click on the name of each variable to access a finder chart and more information about the star.

Stars that can show significant brightness changes over a few hours

Star

RA

Dec

Range

Type

Period(s)

U Cephei 01h02.3m +81o53' 6.7 - 9.3 EA 2.493d
RZ Cassiopeiae 02 49.8 +69 38 6.4 - 7.8 EA 1.195d
Beta Persei (Algol) 03 08.2 +40 57 2.1 - 3.4 EA 2.867d
U Coronae Borealis 15 18.1 +31 39 7.8 - 8.8 EA 3.45d
RR Lyrae 19 25.5 +42 47 7.0 - 8.1 RRLyr 0.567d

 

Stars that show brightness changes over a week, sometimes from night to night

Star

RA

Dec

Range

Type

Period(s)

Zeta Geminorum 07h04.1m +20o34′ 3.7 - 4.3 Cep 10.150d
Beta Lyrae 18 50.1 +33 22 3.4 - 4.3 EB 12.941d
Delta Cephei 22 29.2 +58 25 3.4 - 4.3 Cep 5.366d

 

Stars that show brightness changes over the course of several months

Star

RA

Dec

Extreme Range

Type

Period(s)

Betelgeuse (Alpha Ori) 05h55.2m +07o24' 0.4 - 1.3 Semi Reg 1600d?
Z Ursae Majoris 11 56.3 +57 52 6.3 - 9.6 Semi Reg 195d
RW Bootis 14 41.2 +31 34 7.4 - 8.9 Semi Reg 209d?
Alpha Herculis 17 14.6 +14 23 3.0 - 4.0 Semi Reg 100d, 6yr?
R Scuti 18 47.5 -05 42 4.5 - 8.6 RV Tau 142d
AF Cygni 19 30.2 +46 09 6.4 - 8.4 Semi Reg 92d

 

Stars that show large brightness changes over the course of a year:

The ranges given in brackets for these Mira Type variables are the mean ranges.

The other ranges given are extreme ranges. 

All of these stars can be followed using binoculars when they are near maximum (a couple may be visible to the naked eye), but a telescope will be needed if you wish to follow them all the way down to minimum brightness.

Star

RA

Dec

Range

Type

Period(s)

R Bootis 14h37.2m +26o44' 6.2 - 13.1 Mira 223d
      (7.2-12.3)    
T Cephei 21 09.5 +68 29 5.4 - 11.0 Mira 389d
      (6.0-10.3)    
Omicron Ceti (Mira) 02 19.3 -02 59 1.7 - 10.1 Mira 332d
      (3.6-9.3)    
Chi Cygni 19 50.6 +32 55 3.4 - 14.2 Mira 407d
      (5.1-13.4)    
R Leonis 09 47.6 +11 26 4.8 - 11.0 Mira 310d
      (5.8-10.0)    
U Orionis 05 55.8 +20 10 5.3 - 12.6 Mira 372d
      (6.3-12.0)    
R Serpentis 15 50.7 +15 08 5.7 - 14.4 Mira 357d
      (6.9-13.4)    
R Trianguli 02 37.0 +34 16 5.4 - 12.0 Mira 266d
      (6.2-11.7)    
R Ursae Majoris 10 44.6 +68 47 6.7 - 13.4 Mira 302d
      (7.2-13.0)    
S Ursae Majoris 12 43.9 +61 06 7.2 - 12.7 Mira 226d
      (7.9-11.7)    
T Ursae Majoris 12 36.4 +59 29 6.6 - 13.5 Mira 257d
      (7.7-12.9)    

 

Stars whose brightness changes are totally unpredictable

Star

RA

Dec

Range

Type

Period(s)

R Coronae Borealis 15h48.6m +28o09′ 5.8-15.0 RCB none
           

This category will also include any bright novae that appear.