list of 173 'navigational' stars?
"John Nagelson" wrote:
Unless I am mistaken, though, it gives the list of 57 plus Polaris,
not the 173, although it says the latter is given in the US Nautical
Almanac.
Maybe there is a shareware navigation program somewhere that I can
pick out the
info from???
Any visible star can be used for navigation. The 57 given in
Alamanacs are all bright stars which are not easily confused with
others. The majority of the 173 you will find are sometimes pretty
iffy and any celestial navigator would probaly only resort to them in
fairly awkward circumstances. When you start hitting 3 magnitude and
higher it gets more awkward to distinguish the star one wants from the
background - especially on a ship which may be moving quite heavily.
Brown, for instance, (In the last copy I bought) gives some stars up
to 4 magnitude. But practically, unless you are that rarest of
navigators who can distinguish 173 stars with certainty, anything much
higher than 2 magnitude becomes chancy. Wheras the SHA and Dec of the
57 principal stars are given on the daily pages of nautical almanacs I
don't think I have ever seen the lesser stars listed thus. They are
usually confined to a couple of pages in the back giving the SHA and
Dec for the month only. In principle, unless you plan to sail the
world, you could probably get away with an intimate knowledge of about
sixteen stars in your hemisphere.
Eugene L Griessel
For every person willing to teach, there are 30 not willing to be
taught
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