Celestial Navigation

Modern Celestial Navigation and Calculations

All-in-one tool for modern and accurate celestial navigation.

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Advanced oceanic and land based sight reductions using an offline perpetual almanac. Tool for accurate navigation, education, and training.


Celestial Nav is an easy to use, all-in-one tool which offers:

• Celestial navigational computations for your device

• Simple toolbar menu for quick access

• Internally stored perpetual Almanac

• Offline ready and functional without the need for other external tools

• Quick and easy capture celestial observation data

• High accuracy sight reductions

• Star reference tables


• Local Hour Angle (LHA) for Aries

• Star tables sorted by name, magnitude, declination, and SHA

• Sunrise, sunset, twilight, and location reference

• Moon phase reference


• High accuracy sight reduction algorithm

• Perpetual Almanac offering accurate data for years 1600 - 3000

• Almanac data for Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn

• Detailed Almanac data for 58 navigational stars

• Assumed Position (AP) for any user defined position

• Line of Position (LOP) intercept data for accurate course and speed adjustments

• Computational variables displayed for accuracy and validation


• Computations by USNO algorithm in the Nautical Almanac

• Save all your LOP in an easy reference table


Free daytime celestial navigation tools using the sun:

• Unlimited sextant sight reduction calculations

• Sight reduction to a line of position using the sun

• Perpetual almanac for the sun

• Advanced sight corrections for index error, eye height, temperature, and pressure

• Support for upper and lower limb reference

• Star Table with navigational references

• Detailed Sun references

• Limited Moon references


Advanced Day & Night Celestial Navigation includes all BASIC features plus:

• Almanac data for 65 navigational bodies for years 1600 through 3000

• Metric and imperial unit support with automatic conversions

• Support for coordinate entries in different formats (H° M’ S” or Decimals)

• Save all your LOP calculations for future reference

• Save user preferences and settings

• Unrestricted moon references

• Almanac and algorithmic models for 65 navigational bodies:

• Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn

• 58 navigational stars


Supported stars: Acamar, Achernar, Acrux, Adhara, Aldebaran, Alioth, Alkaid, Al Na'ir, Alnilam, Alphard, Alphecca, Alpheratz, Altair, Ankaa, Antares, Arcturus, Atria, Avior, Bellatrix, Betelgeuse, Canopus, Capella, Deneb, Denebola, Diphda, Dubhe, Elnath, Eltanin, Enif, Fomalhaut, Gacrux, Gienah, Hadar, Hamal, Kaus Aust., Kochab, Markab, Menkar, Menkent, Miaplacidus, Mirfak, Nunki, Peacock, Polaris, Pollux, Procyon, Rasalhague, Regulus, Rigel, Rigil Kent., Sabik, Schedar, Shaula, Sirius, Spica, Suhail, Vega, Zuben'ubi


Sight reductions and celestial calculations use various internationally accepted references for the most accurate results:

• Jean Meeus - Astronomical Algorithms

• US Naval Observatory (USNO) Almanac and Algorithms

• Hipparcos New Astrometric Catalog, Published 2007

• ELP2000-85


Celestial Nav is free to download and the basic features free to use. A paid upgrade to the PRO version provides access to premium features and additional tools.

We offer trial subscriptions that give limited time access to all PRO features and premium content for the duration of the trial period. Trial subscriptions automatically expire and the app will revert back to the Basic version thereafter. No data is lost but access and use of premium features will no longer be available.