Common Abbreviations and Acronyms Used in TheSky6

Abbreviation/Acronym

Definition

Alt

Altitude

AU or au

Astronomical unit. This is the mean distance between the earth and the sun.

Az

Azimuth

Dec

Declination

FOVI

Field of view indicator

GSC

Guide Star Catalog

IAU

International Astronomical Union

IC

Index Catalog

lt-yr

Light year. The distance light travels in on year’s time.

mas

Milli-arcseconds

NGC

New General Catalog

PGC

Principle Galaxy Catalog

RA

Right ascension

SAO

Smithsonian Astrophysical Observatory

UCAC

USNO CCD Astrograph Catalog

USNO

United States Naval Observatory

yr

Year