Affiliation
URSA Astronomical Association, Variable Star Section (Finland) (URSA)
Tue, 07/24/2012 - 10:32
I have been making plans for the starting dark sky -season. I live in Finland, and we still have light nights because of summer, but soon the nights are getting dark again.
I have been thinking a strategical question regarding my plan, the question is: should I focus on observing stars with a such amplitude, that I can cover the whole cycle with my 4'' refractor or should I also observe stars that I can monitor only when they are bright enough that I can see them with my small refractor? What do you think about this question? I would be happy to hear any opinions and recommendations!
-Juha Ojanperä (OJMA)
Hi Juha,
I would start by making a list or spreadsheet with only stars you can see throughout their cycle. You may be surprised at how many fun and interesting stars that gives you! There are a lot of interesting Miras and SRs you could observe. The SRs tend to be a little less predictable. You can probably do SS Cyg all the time depending on how dark your skies are also.
Then if you think you need more targets, based on the frequency of your observing, your enthusiasm and the weather, I'd start adding LPV Legacy List stars, especially those that are circumpolar for you that you can follow almost all year, when it gets dark anyway.
Mike
Juha - My outlook concerning your question is rather different than Mike's take on this matter. In my opinion your best approach would be to follow a wide selection of stars that are within the range of your instrument when bright, always checking beforehand that the stars are anticipated to probably be bright enough to be seen currently. This can be ascertained through the use of the AAVSO's prediction tables. In the case of observing with small instruments, one wants to generally avoid reporting really bright "fainter-than" estimates as they are generally of little value.
I base my opinion on the fact that I'm seeing a number of observers these days apparently selecting only a limited number of variables to follow and then over-observing them. In fact, we've only recently had a discussion of appropriate observing intervals and over-observing. Some instances of nightly estimates of slowly changing Miras I consider particularly disturbing as they not only are wasteful of the observer's time, but also potentially give excessive weight to a single observer when compiling the combined lightcurves.
So, while each observer's program will be different and dependent on their specific limitations, my advice would to be observe as many stars that are within your instrument's range as you are comfortable with.
J.Bortle (BRJ)
Juha, I commonly observe with a Televue NP-101 4" refractor. Since your visual observing season is shorter than most observers, I would probably follow John Bortle's advice and try to observe a diversity of targets, honoring the recommended observation interval. There are plenty of Mira's, SR's, RV Tauri and other variable stars types to choose from. I would look at the LPV Circular, the AAVSO's Observation Planning Tool and Tom Bretl's spreadsheet tool for possible targets. I look at other observers and their program stars on the Yahoo VSObs Group for additional targets of interest. If you find your visual observing season too limited, you may also may want to investigate remote CCD observing using Sierra Stars, iTelescopes or other remote observatories during your "white nights." This may help to add more targets of interest and extend your observing season to all year round. There are many variable stars and possibilities to explore. Best of luck and clear skies. Kevin Paxson - PKV
I'd add some symbiotic (ZAND) and RCB stars to the list too...
Many thanks for you all for your comments and advise, I appreciate it! An idea of observing a large variety of stars within the range of my scope sounds good! Currently I have several kinds of variables in my personal observing programme but LPVs are quite emphasized. So adding also some other kinds of stars might be a good idea!
I also got extremely inspired about the SS Cyg observing campaign mentioned in the list of AAVSO observing campaigns! It sounds really good, and the knowledge of the fact, that by observing the star, you are intimately participating in making real science is really motivating and fascinating! So I think I'm surely going to observe SS Cyg too!
I'm very excited about the starting dark sky -season already! Actually we are getting deep nautical twilight here already, so the properly dark nights aren't that far away anymore!
-Juha Ojanperä (OJMA)