Something you need to consider carefully, and a question that comes up often with new observers is "How often should I observe my program stars?" The answers depend largely on the type of stars you are observing. The following table is a general guideline. As you learn more about the different types of variables, and the personalities of some of the specific stars you choose to observe, you may decide to observe them more or less often than suggested here.
On the other hand, please be careful not to observe a star which is not changing rapidly too often. This can bias your own observations as well as the light curve.
|
Variable Type |
Cadence in days |
|
Active Galaxies (AGN) |
1 |
|
Gamma Cassiopeia (GCAS) |
5-10 |
|
Irregular |
5-10 |
|
Miras (LPVs) period <300 days |
5-7 |
|
Miras (LPVs) period 300-400 days |
7-10 |
|
Miras (LPVs) period >400 days |
14 |
|
Novae (N) |
1 |
|
R Corona Borealis (RCB) - during max |
7 |
|
R Corona Borealis (RCB) - during fadings |
1 |
|
Recurrent Novae (NR) |
1 |
|
RV Tauri (RVTAU) |
2-5 |
|
S Doradus (SDOR) |
5-10 |
|
Supernovae (SNe) |
1 |
|
Semi-Regular (SR, SRA, SRB, SRC) |
5-40 |
|
Dwarf Novae (NL, UG, UGSS, UGSU, UGWZ, UGZ) |
1 |
|
Young Stellar Objects (YSOs) active state |
1 |
|
Young Stellar Objects (YSOs) inactive state |
2-5 |
|
Symbiotics (ZAND) |
7 |
|
Symbiotics (ZAND) - during activity |
1 |
Observers following eclipsing binaries, RR Lyrae and UGSU in outburst should consult the section leaders for the preferred cadences for time-series type observations of these stars. You may need to observe them from every 30 seconds to every ten minutes depending on the type of variable and its period.