Quote:
Originally Posted by JohnOS
Hello
I have been reading the pdf manual supplied with my argo-navis and servocat but l am still struggling with some of the features.
I enjoy observing double stars and noticed that the designated double star names on charts and catalogues do not relate to the argo-navis details which are Arabic letters, Dunlop 10, H and numerical three digit numbers.
I am sure there is a simple explanation but due to my inexperience I am confused.
All assistance will be greatly appreciated.
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Hi John,
Thanks for the post and for recently purchasing an Argo Navis.
The BRIGHT STARS catalog contains a selection of bright stars down
to magnitude 6.5, particularly those with well-known historical names
such as Betelgeuse and those with Bayer Greek alphabet or
Flamsteed nimbers. Names have constellation abbreviation first, then
Bayer or Flamsteed identifier. For example FOR ZETA for Zeta Fornax.
They are ordered that way to make the catalog easier to browse.
Many of the stars within the BRIGHT STAR catalog are doubles and
their scrolling descriptions describe them as such. For example Acrux,
Gamma Velorum (VEL GAMMA) and so on.
The MISC DOUBLE STAR catalog then contains a selection of double
stars that do not appear in the BRIGHT STAR catalog. These are listed
by the most popular designators used by most double star enthusiasts.
For example, DUN 10 is Dunlop 10 in Horologium which is from the
famous catalog James Dunlop produced from observations in Parramatta
between 1823 and 1826.
See
http://en.wikipedia.org/wiki/James_Dunlop
See also -
http://www.southastrodel.com/Page033.htm
In the later article by Andrew James cited above, Andrew mentions
what he terms "likely the greatest double star observer of all,
Frederick
William Struve (1793-1864)". Struve doubles are designated by enthusiasts
by the
capital Greek letter Sigma (Σ). Argo Navis does the same,
so for example Σ 1200 is Struve 1200 in Lynx and so on.
The grandson of Frederick was
Otto Struve and double star enthusiasts
prefix his double stars with a OΣ designation. Again, so too does Argo Navis.
Before the Struves was William Herschel and historically enthusiasts
designate his doubles with a capital H. Those by John are typically
prefixed with a lower case h.
The Greek β designation is the prefix most popularly used for stars
from the
Burnham Double Star Catlogue
No "Arabic letters" ever appear in common double catalogs. There are
Greek letters.
HDO is the most common prefix for stars from the Harvard Observatory
and so on.
One good reference are the three volumes of the Burnhams Celestial Handbooks.
It is important to keep in mind that most objects, including stars, have
multiple designations. Argo Navis tends to favour the most historically
common wherever possible.
By the way, the next firmware release of Argo Navis is currently in Beta
test and includes a newly revised MISC DOUBLE STAR catalog.
Thanks again for the post.
Best Regards
Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place, Mount Kuring-Gai
NSW. 2080. Australia
Phone +61-2-9457-9049
Fax +61-2-9457-9593
sales@wildcard-innovations.com.au
http://www.wildcard-innovations.com.au
