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Software Products

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MICA - Multiyear Interactive Computer Almanac

MICA CDROM (thumb)MICA is an easy-to-use program that computes many of the quantities that are tabulated in The Astronomical Almanac, but covers the 250-year period, 1800-2050. It allows the user to compute this information for specific locations and specific times and is available for both PC and Macintosh computers. MICA includes several catalogs of celestial objects, including a new astrometric catalog containing about 230,000 stars. Current version: 2.2.2.


NOVAS - Naval Observatory Vector Astrometry Software

NOVAS iconNOVAS is an integrated package of subroutines and functions for computing various commonly needed quantities in positional astronomy. Available as Fortran, C, or Python source code. Current version: 3.1


Software Products by Our Colleagues

NavPac and Compact Data 2011-2015

This product is a publication of Her Majesty's Nautical Almanac Office (HMNAO) of the United Kingdom. The NavPac software, supplied on CD-ROM, enables navigators to easily compute their position at sea from observations made with a sextant. Compact Data, the book supplied with NavPac, provides simple, efficient and consistent formulae and methods for calculating the positions of the Sun, Moon, navigational planets, and stars, as well as sight reduction using a personal computer or programmable calculator.

Standards Of Fundamental Astronomy (SOFA) Libraries

The International Astronomical Union's SOFA initiative seeks to promulgate an authoritative set of fundamental-astronomy constants and algorithms. The initiative is managed by an international panel, the SOFA Reviewing Board, appointed through IAU Division 1. The SOFA software libraries are a collection of subprograms, in source-code form, that implement official IAU algorithms for fundamental-astronomy computations. Visit the SOFA Web site for details.


Discontinued Naval Observatory Software

Floppy Almanac

Interactive Computer Ephemeris (ICE)


Specialist Software

USNO/AE98 - ephemerides for fifteen of the largest asteroids. This software is written in C and designed to work along with the C version of NOVAS.