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A new catalog ideal for star chart

The UCAC3 star catalog was published by USNO at the end of august.
Its main characteristics are:

  • Full sky coverage
  • 100 million stars
  • Complete down to magnitude 16
  • Good resolution of double stars
  • Incredibly complete in crowded field
  • Proper motions for every star
  • Native magnitude in 579-642 nm bandpass
  • Include photometry from 2MASS and SuperCosmos
  • Flags to match stars on other catalogs
  • Imprecise or missing bright stars

From this characteristics a catalog is build for use with Skychart software.
The information for each star include: identifier, RA, Dec, aperture magnitude, proper motion, approximate color index (from SuperCosmos B and R2).
To solve the problem with the missing bright stars it not include any star present in Tycho2 catalog or any star brighter than magnitude 10. This implies you must always activate the Tycho2 at the same time with this catalog.

To use this catalog start by getting the part you need from the download catalogs page.
It is split in three part so you can get only the zone visible from your area.

  • : South zone -90 to -30
  • : Equatorial zone -30 to +22.5
  • : North zone +22.5 to +90

A fourth file contain the optional search index for all the zones.
Each file is about 500MB is size.

Extract all this zip under ciel\cat or share/skychart/cat. As each file is autonomous there is two common file on each, when prompted for replacement you can respond yes or no without effect.

Then from Skychart open the menu Setup -> Catalog, click the *Add* button and select the file 3uc.hdr.
Then open the Cdc Stars section to activate Tycho2 and disable the GSC

My preferred star catalog setting for general use is now:

Catalog Field number Field degrees
Bright Star 0 - 10 0 - 360
Tycho 2 0 - 6 0 - 45
3UC 0 - 3 0 - 5
en/news/ucac3_catalog.1254558627.txt.gz · Last modified: 2015/11/06 20:35 (external edit)