TheSky6's Databases Explained

Software Bisque's goal with TheSky6 is to provide a comprehensive set of astronomical databases and the tools to quickly access information from them. TheSky6's "core" databases include extremely accurate, industry-standard astronomical catalogs. They should meet your needs whether you're star hopping with your telescope, taking CCD images of faint galaxies, or computing sub-arcsecond astrometric positions of minor planets.

TheSky6 (Professional, Serious Astronomer and Student Edition) displays celestial objects and other screen elements from a wide variety of sources, included user-defined data. There are four general database categories displayed by TheSky6.

Core Databases

TheSky6 contains databases of celestial objects from the following standard astronomical catalogs. The information in these catalogs has been stored in an optimized file format so that TheSky6 plots and accesses information quickly.

Use the Edit | Find command to locate any object from any of these catalogs.

Optional Stellar Databases (Professional Edition)

TheSky6 Professional Edition can display stars from the following optional (not included) stellar databases.

These databases, not provided with TheSky6, may be obtained from the U.S. Naval Observatory using the following procedure.

1. Download the catalog from the U.S. Naval Observatory Flagstaff Station's ftp site. Files that have the ".cat" and ".acc" extensions are required and should be copied to a single folder on your hard drive.

2. These files can reside in any folder. By default, TheSky6 looks to the USNO A2.0" folder in TheSky6's Data\Core Databases folder for these files. To configure TheSky6 to use a different folder, click Data | File Locations, and then edit the name of the USNOA 2.0 directory.

3. To display stars from the USNO A2.0 database, click View | Stellar Options, click the Catalogs/Astrometry tab, mark the USNO A2.0... option and then click OK.

Cross Referenced Catalogs

TheSky6 also cross-references the following catalogs. Use the Find command to locate any object from any of these catalogs.

Sky Databases (SDBs)

TheSky6 includes the additional "non-standard" astronomical catalogs and as optional Sky Databases. Use the Find command to locate any object from any of these catalogs.

Ephemeral Data

TheSky6 can display the positions of comets, minor planets and satellites. The data required to accurately display these objects changes frequently and must be updated from different sources on the worldwide web. Use the links below to download updated orbital element data.

Use the Find command to locate any object from any of these catalogs.

User-Defined Data

TheSky6 allows you to create user-defined objects (such as stars, galaxies, labels or reference lines) so that you can generate your own databases.  See the Add User-Defined Data command for details.

Digitized Sky Survey

See the Digitized Sky Survey Introduction for details about accessing and displaying high-resolution photographs (1.7 arcseconds/pixel) for the entire celestial sphere.

Want More Data?

There are literally thousands of astronomical catalogs. If TheSky6's databases of up to a billion objects is not enough, and you wish to access a database that is not currently included, please let us know, and we'll try to incorporate them in future updates.

Missing or Anomalous Catalog Data

You may notice some irregularities in the stellar and non-stellar catalog data.

Errors in the astronomical catalogs are caused when photographs are

scanned, or by human error.

Diffraction Spikes and Halos

The areas around some bright stars do not show any dim, high-magnitude

stars. The “empty” areas take the form of halos or diffraction spikes. These

optical artifacts obscure dimmer objects on the photographic plates from

which the GSC data are derived.

“Burned-Out” Areas

The GSC data were derived from photographic plates given heavy exposure

to bring out detail. As a result, the central regions of globular clusters and

bright nebulae are sometimes overexposed, and show no detail. This can be

seen (for example) as an empty square area in NGC 5139. It is also the reason

why the Trapezium shows little detail.

Missing Data

There are no data for several areas. In particular, there is a blank rectangular

region in Hercules, at about 17h 20m RA, 33º 13' Dec. (The Hipparcos- Tycho

catalogs include some of the brighter stars in this region.)

Anomalous Data

There are two rows of “stars,” centered at 22h 10m 34.5s RA, -11° 38' 12"

Dec, and 22h 08m 17.6s RA, -11° 39' 53" Dec.

Other Errors…?

The contracts under which Software Bisque provides astronomical databases

prevent us from adding to or altering them. If you find any errors or

omissions, please let us know so we can report them.