Variable Stars

[Solanum]

How do amateur astronomers (I'm assuming the professionals measure it electronically) estimate magnitudes of variable stars? Is it a matter of experience and comparing with non-variable stars of a known magnitude, or is there some other system?

[Dujon]

I think that you will find that the answer is pretty much in line with your thoughts, Everard. In any field of view there will be stars which are considered to be non-variable and have a standard 'brightness' designation. It's then a simple task to compare the variable star being observed to the known values of the field star 'neighbours'.

In theory.

I doubt though that it's really that simple and suspect that a good deal of self training would be required to attain the level which many visual variable star observers have reached.

[Solanum]

Oh, I've no doubt a lot of experience is needed to do it properly! :) However, if there was a fairly bright variable visible for much of the year, with appropriate field stars to compare with it would be quite fun to have look each time one was out observing and plot your own observations over time. Thus I was wondering what the techniques really are.

[Dujon]

Everard,

I'm sure that you will receive further responses from other members in due course (in our time zone it is lunch time/barbecue time at the moment).

In the interim this site http://www.aavso.org/observing/ might give you some clues.

[Solanum]

Same time zone as me! Bit cold for a BBQ though....

Thanks for the link, I've downloaded their visual observing manual and I'll see if there is anything simple enough for me to have a go at - I'd still appreciate any pointers though.

[[1ponders]]

Johns onto the right link there Everard. the aavso sight will contain everything you wanted to know about visual variable observing but were afraid to ask. :)