Variable Stars

[neoterryjoe]

Hi all,
Was wondering who keeps track of variable stars in this forum.. Hope there is some reply..would like to do some observations on this interest..

[gchew]

I used to... and I'd submitted some observations to AAVSO too. With x70 binoculars, the limiting magnitude in Singapore is about mag 8+, well within the magnitude range of many variables. Haven't had the chance to do much variable star observing in the past months though.

[weixing]

Hi,

Was wondering who keeps track of variable stars in this forum.. Hope there is some reply..would like to do some observations on this interest.

I also quite interest, but have problem estimate brightness... May be I just need to practise...

I used to... and I'd submitted some observations to AAVSO too. With x70 binoculars, the limiting magnitude in Singapore is about mag 8+, well within the magnitude range of many variables. Haven't had the chance to do much variable star observing in the past months though.

Oh... May be you can share with us your experience??

Have a nice day.

[neoterryjoe]

yep! please share with us! there are 2 lists of variable stars in aavso which are recommended for beginners.. some have little variations in magnitude and some have long periods between the extreme magnitudes(like a few years). I wonder why are they still considered in this list or to rephrase, what are the criterias for a var star to be considered as an easy var star for ob...

[Tachyon]

I once joined the BAA Variable Stars Section when I was 16 yrs old, but sadly never submitted any observations.

[gchew]

yep! please share with us! there are 2 lists of variable stars in aavso which are recommended for beginners.. some have little variations in magnitude and some have long periods between the extreme magnitudes(like a few years). I wonder why are they still considered in this list or to rephrase, what are the criterias for a var star to be considered as an easy var star for ob...

Some variables are in the "easy" category for a few reasons. Their brightness variation might be sufficiently large so that their variability is detectable between subsequent observations spaced an appropriate duration apart. They are easy to locate, as opposed to variables in rich starfields, where another star can be mistaken for the variable (and this itself may or may not be visible). Some stars are less prone to the Purkinje effect, which tends to cause overestimates of a star's brightness. It also helps to have good reference stars nearby.

AAVSO publishes charts that show the field in the vicinity of variable stars. Certain constant magnitude stars are marked with their magnitudes on these charts, and can be used as reference when estimating the variable's brightness. There are at least two ways to do a visual estimate - 1) find two reference stars whose magnitudes contain that of the variable, then roughly interpolate to get the magnitude of the variable, giving the estimate to one decimal place; 2) As before, find two suitable reference stars, then estimate the variable's magnitude as a fraction of the magnitude difference between the two reference stars. The estimate can be calculated if we know the magnitudes of the reference stars.

So much for visual estimates for tight-budget folks like me... A whole new world of photometry and astrometry opens up if you own a CCD. I believe there are people on the list who have the necessary equipment to conduct CCD estimates. Is anyone doing that currently?

[makoto™]

wat are variable stars?

[weixing]

Hi,

wat are variable stars?

Basically, variable stars are stars that change in brightness.

See this link for more information: http://en.wikipedia.org/wiki/Variable_star

Have a nice day.

[makoto™]

ah..thx for the info =D

[ricochet]

This is an old thread but I would like to know if some members are interrested on observing/photographing variable stars?
I just started and it would be nice to meet others to share experience.