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Stargazer_10
21-04-2013, 12:58 PM
I just bought a 10" Bintel Dobsobian, I am a beginner and I was just wondering, how do you find variable stars? What do they look like?

Robh
22-04-2013, 11:51 AM
Variable stars pretty much look like any other star but they vary in brightness over time. This variation can occur in minutes, hours, days or years. It may, for example, be due to a star pulsating (swelling and shrinking) or due to an orbiting companion (eclipsing binary). A star can actually change in spectral type over a cycle if it swells and its outer surface cools e.g. go from K8 to M2.

A list of variable stars is here ...
http://en.wikipedia.org/wiki/List_of_variable_stars

For more info and if you wish to contribute to observations of variable stars look here ...
http://www.variablestarssouth.org

and here ...
http://www.aavso.org

Regards, Rob

Stargazer_10
22-04-2013, 04:13 PM
Thanks for the information, I'll take it into account

Wavytone
23-04-2013, 02:44 PM
Start here...

http://www.southastrodel.com/Page029a.htm
http://www.southastrodel.com/PageDSIndex.htm

alan plummer
23-04-2013, 05:14 PM
Hi. A 10" dobson opens up uncounted thousands of objects to observe. When I say 'observe' I don't mean to look at, but more to gather data.

There are many colaborations to participate in, for instance, with the Hubble team, and many others. The AAVSO co-ordinates these. You already have that address. The VSS is where you will meet the locals, and participate in southern research projects.

Do some reading. The AAVSO 'visual observers manual' is a free download, and the most important to see. 'Astronomy 2013' has a bit in it about VSOing - at the back of the book, in one of the Apendix's.

First tip: Find targets to do from home, despite posible light polution. (I've done the experiment, and taken my 12" dobson to Sydney Observatory and done my list of targets from there. Not only was it fine, but one of the observations ended up generating a paper in A&A.) Dont think you will travel to a dark sky to observe. It won't work.

Contact me any time at alan@alplummer.com.au

Alan Plummer

faaarwest2k
24-04-2013, 08:23 AM
Variable Star observing is something I would like to do.

Suzy
24-04-2013, 10:53 AM
This is a really terrific book & worth every penny!

Observing Variable Stars: A Guide for the Beginner (http://www.bookdepository.co.uk/Observing-Variable-Stars-David-Levy/9780521627559), by David Levy.

I have it and David Levy explains things so well with such enthusiasm- an easy read/guide.

A good one to start out with I guess would be Algol- The Demon Star.
It's a bright star looking north in the constellation of Perseus, easily visible to the naked eye. It's brightness changes every 2 days. Apparently you can observe these changes during the course of an entire night's observing. :eyepop: Wait a few months for the constellation to be in our skies again.
http://en.wikipedia.org/wiki/Algol Keep scrolling down & check out the animation!

In 2011, the star Mira was an awesome site to see. All of a sudden there was a bright orange star in the constellation of Cetus. It was so much fun watching it slowly fade.
http://www.skyandtelescope.com/observing/highlights/130722493.html

And read here: http://www.oneminuteastronomer.com/258/mira-wonderful-star/

I'm not an expert here in variable star observing- I've not actually done it yet in any serious way, but someday I hope to. :)


Does anyone know when Mira will get so bright again?

alan plummer
24-04-2013, 06:23 PM
Hi Suzy. Mira is predicted to reach max light on july 16 2013, acording to the AAVSO buletin 76. However, it rarely gets as bright as the recent peak. But who knows? To quote somebody or other, there is nothing simple about the light curves of Miras.

Davis Levy's book is wonderful, and among a few others, great to have on the shelf. But if one wants to start observing, there's no escape from the Observer's Manual.

There's no need to do Algol, leave that to the northeners. You'll find useful southern targets suitable for beginers in the references cited in my previous post, and in Australian Sky and Tel.
Best. Alan.

Suzy
24-04-2013, 07:54 PM
OMG you're "THAT" Alan Plummer. :ashamed: <----insert more blush.
I'm so red faced right now, Alan!

I have a huge amount of respect for the work that you do, wow... fancy that....! I'm still stoked, sorry. :lol:
I see your articles in AS&T all the time. :D

Just curious, why not Algol? It's an easy catch for me albeit sitting low on my horizon. I thought it would have been good to give a whirl on? I admit, I do love that star when it shines and the story attached to it.

Many thanks for the information on Mira. I had a ridiculous amount of fun with it when it reached that incredible peak. Even if it gets "just" visible- I can't wait to observe it's decline again. :thumbsup: