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Just submitted my first serious estimate!

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#1 Michael Rapp

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Posted 18 December 2012 - 10:02 PM

After practicing for a few weeks, I decided to try my first serious variable star estimate. I picked a star that would be in the range of my binoculars (even with the moon up): Rho Cassiopeiae.

The field is easy to find being just a few degrees west of Beta Cassiopeiae. I chose this star for two reasons, 1) I had not observed it before so I had no preconception of how bright it is/should be and 2) a decent number of companion stars are around it.

So, this evening, I printed out the appropriate AAVSO chart from the VSP and put the lawn chair out, sat down, waited for the Big Outdoor Cat to sit in my lap, flipped to the right page of the Pocket Star Atlas, and went to locate the field.

Once I found the star, I put the PSA aside, petted the cat, and rotated my AAVSO chart to fit the field orientation in my binoculars. I doubled-checked to make sure I did indeed have the right star and that the other star patterns matched up.

I picked a companion star of 6.6 magnitude. Well, this was easy. Rho Cas was easily brighter than that. So I went to the next brightest companion star, one of 5.5. Here, the brightness was closer so I alternated putting Rho Cas in the center of my field and then the 5.5 companion star. Yep, Rho Cas was brighter. So I went to the next brightest star, one of 4.9.

Here, the estimate got tougher. The stars seemed exceptionally close in brightness, but not exactly identical. I went back and forth between the two stars, centering each in the field of view. I even took a break a few times to relax my eyes.

I consulted Big Outdoor Cat, who insisted the magnitude was purr-point-purr, but my cat-speak is a little rusty, so I went back to the binoculars. After much contemplation -- perhaps a bit too much -- I decided that Rho Cas was ever-so-slightly brighter than the 4.9 companion star, so at 2:22 UT, I wrote down: 4.8 and circled the two other companion stars on the chart.

That was fun and, to my surprise, incredibly relaxing. I wonder what the next star on my list will be?

#2 Hubert


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Posted 19 December 2012 - 01:00 AM

Hello Michael,

congrats on your first variable star estimation.

Wasn't there a comparisonstar available that was brighter than the 4.9? So that you could compare Rho between those two compstars?


#3 MG1962


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Posted 19 December 2012 - 02:30 AM

Congrats - you are now a serious researcher who personally delivers your findings to the AAVSO.

And I am not sure how many estimates you need to do to qualify, but you are now in the running for a Christmas card from the AAVOS next year :)

#4 Rich (RLTYS)

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Posted 19 December 2012 - 08:04 AM

Good luck with your VSOing.

Rich (RLTYS)

#5 RAKing


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Posted 24 December 2012 - 07:16 AM

Congrats and welcome to the club! :bow:

I wish my cats could sit in my lap, too. :)



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