Re: [guide-user] GOTO UCAC4 Object
Bill Gray Oct 6 7:03 AM
As Steve Messner suggested, you're better off going through the
generic 'Go to Object' method. That's true for a couple of reasons.
First, 'Go to Object' is much less picky. To take Steve's
example, '4UC 468-010262' or '4u468-10262' would be accepted;
i.e., you can stick in spaces, use lowercase, drop leading
zeroes, and be Just Fine. 'Go to TDF' requires three digits,
a '-', and six digits.
But second and more important... 'Go to TDF' will, for UCAC-4
(and other UCACs) only work if the object is already on the screen!
Drawing of these datasets is accomplished by having Guide extract,
from the multi-gigabyte raw binary dataset, just the data covering
the current screen area. That data is stored in text form in
'ucac4.txt' (or 'ucac3.txt', etc.) And it's that text file which
Guide displays, and which Guide uses when you 'Go To TDF Object'
for UCAC-n data.
There are similar, though slightly different, issues with 'Go
To TDF Object' with data downloaded from VizieR (GSC-2.3, 2MASS,
B1.0, CMC-14, etc.) In those cases, you're gradually gathering
pieces of the catalogs, through Extras... Get Star Catalog Data.
The data accumulates, and you can 'go to' a B1.0 or GSC-2.3 star...
but only if it's one that you already downloaded.