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From: TerryMoselaol.com
Date: Sat, 12 Jun 2004 19:59:21 EDT
Subject: Delta Sco IS bright!

Hi all,

I got a much better brightness estimate later tonight, when Delta Sco & Spica 
were about the same altitude above the horizon.  Both are the same colour, 
giving a more reliable comparison. At 00.50 (23.50 UT on 12 June) I estimated 
that Delta Sco was only 0m.4 fainter than Spica, making it 1m.4, or 0m.9 
brighter than its quoted magnitude of 2m.3.

It is officially recognised as variable, but with a range of less than 0.06 
magnitudes, much less than the current apparent variation.

Since it is a spectroscopic triple star, and an 'occultation quadruple star' 
(i.e. there's a fourth component revealed during accurate analysis of lunar 
occultations, but too close to be detected by other means), it's obviously an 
interesting system! The distance is about 400 LY.

If anyone is going to a much more southerly latitude for a holiday, have a 
look: compare it with Spica, Antares, Lambda Sco (last star in the 'tail') = 
1m.6; and Epsilon Sgr (bottom right of the 'teapot') = 1m.8.

Clear Skies,

Terry Moseley

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