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Old 01-03-2008, 09:30 PM
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ngcles
The Observologist

ngcles is offline
 
Join Date: Dec 2006
Location: Billimari, NSW Central West
Posts: 1,664
Hi Goober & All,

Excellent report -- a good read as usual.

Re your observation of Sirius and Sirius B.

It is pretty diifficult for me to judge one way or the other, but I am inclined to say it probably wasn't the pup baised on your drawing:

From the drawing, "the pup" is definitely shown in the wrong PA. According to "The sixth catalog of orbits of binary stars: Ephemerides" -- in 2008.1, the seperation is 8.039" in PA 98.1. For 2009.1 it is 8.435" in PA 94.6. So from that, being now March 2008, the PA would be approx 97.2. From your drawing, you have it in about PA 165 odd (assuming N is approx top right in the drawing). Just so you know the same catalog has Algieba in 2006 as 4.609" in PA 125.7 and in 2009 4.612" in PA 125.7 (unchanged).

But then again, maybe the drawing is wrong? I checked this idea on Megastar with an 18 arc-min field and I can't quite match that "W" shaped asterism that you have drawn approximately west of Sirius. Instead the best match for that group of stars on Megastar, is a group almost due E by pretty much the same distance you have drawn it to the West. Maybe the drawing is in error? Maybe it isn't -- hard to tell. You are a naughty boy for not indicating North!

I don't doubt for a moment that you saw some sort of faint mote in close to Sirius, but I can't really say whether it was the pup or not based on the drawing. More likely nay than yea, but really can't say!

To eliminate the possibility of it being an internal reflection, observe it (move it around) in all four quadrants of the field of view of the eyepiece, just marginally away from dead centre of the FOV. If the PA and/or seperation shifts, you have an internal reflection.

Yes, you do have very very neat handwriting!

Best,

Les D
Contributing Editor
AS&T
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