Tools

LINKS

Last revision: June 2025

SOFTWARE LINKS

All software is free and fully functional.

PC Chart plotter and GPS Navigation software:

• OpenCPN (WindowsOS, MacOS and LinuxOS).

• SeaClear (WindowsOS).

Celestial Navigation software:

• AstralNav (WindowsOS).  The AstralNav software is designed to calculate the geographical position of a user, from celestial observations, (like those from a sextant).

• AstroNav (WindowsOS). Electronic Nautical Almanac that includes a comprehensive catalogue of stars.

Virtual Planetariums:

• Stellarium (WindowsOS, MacOS and LinuxOS).

• Skychart (WindowsOS, MacOS and LinuxOS).

GRIB File Viewers:

• ZyGrib (WindowsOS, MacOS and LinuxOS). GRIB (GRIdded Binary or General Regularly-distributed Information in Binary) form is a concise data format commonly used in meteorology to store historical and forecast weather data. It is standardized by the World Meteorological Organization's Commission for Basic Systems.

Office suites:

• LibreOffice (WindowsOS, MacOS and LinuxOS). LibreOffice uses the Open Document Format for Office Applications (ODF), or OpenDocument, an international standard developed jointly by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). LibreOffice also supports the file formats of most other major office suites, including Microsoft Office, through a variety of import and export filters.

Operating Systems:

• Navigatrix is a compilation of electronic tools for navigation, communication, information and security that you can use offshore, on shore, or at anchor. It is simple and lightweight and based on the best Debian/Ubuntu has to offer. Is nearly indestructible running on a 4 gigabyte, or larger, USB stick or SD card. It allows access to your hard drive data if you choose, and even works if your hard drive doesn't.

  • • To create a bootable USB memory you will need: A 4GB or larger (8 or 16GB for a standalone run is recommended) USB stick/flash drive, an computer or laptop running WindowsOS, MacOS or LinuxOS and the Navigatrix ISO file (version 0.5 - 32 bit).

    • Prepare the USB stick: Set the format to MS-DOS (FAT) and the scheme to MBR Partition Map for old computers.

    • Install and run Etcher: To write the ISO file to the USB stick, you can use a free and open source application called balenaEtcher.

    • Running Navigatrix on newer hardware (2011+): While Navigatrix version 0.5 will run on (U)EFI machines, you may have trouble installing it in “Dual Boot” mode alongside another operating system. See this post on the Navigatrix discussion board for further details.

METEOROLOGICAL LINKS

Weather Services:

• Windy - Windy is a Czech company providing interactive weather forecasting services worldwide. Currently, weather forecasts are based on data from the GFS models, ECMWF, and NEMS model from the Swiss company Meteoblue.

• PassageWeather - PassageWeather was developed out of the need for accurate, reliable and easy to use weather information and forecasts. We provide 7-day Wind, Wave and Weather Forecasts to help sailors with their passage planning and weather routing.

• MetOffice - The Met Office (officially the Meteorological Office until 2000) is the United Kingdom's national weather service.

  • • Synoptic Maps

• WindGURU - WindGURU is a service specialized in forecasting weather. Forecasts are based on data produced by weather forecast models. Windguru is able to provide forecasts for any place on planet Earth. The main reason to create this site was the idea to get the forecasts quickly and easily without wild clicking the mouse while searching for meteomaps throughout the internet.

• Weather forecasts - Thomas Krüger Weather Service. Weather Open Port Guide puts weatherforecasts into graphs.

PROGRAMS AND UTILITIES LINKS

• ADMIRALTY EasyTide - Comprehensive tidal prediction service Online.

• Unit Converters - Provides a convenient means to convert between the various units of measurement within different systems, as well as to provide a basic understanding of the systems currently in use, and how they interact.

• Radio Garden - Allows listeners to tune into live radio across the entire globe.

• Nautical Free - Online free nautical charts and publications. A very comprehensive site providing a huge amount of information covering all aspects of the maritime world.

• OpenSeaMap - The free nautical chart. OpenSeaMap is an open source, worldwide project to create a free nautical chart. There is a great need for freely accessible maps for navigation purposes, so in 2009, OpenSeaMap came into life. The goal of OpenSeaMap is to record interesting and useful nautical information for the sailor which is then incorporated into a free map of the world. This includes beacons, buoys and other navigation aids as well as port information, repair shops and weather maps. OpenSeaMap is a subproject of OpenStreetMap and uses its database.

ASTRONOMY LINKS

• The Nautical Almanac - The free online Nautical Almanac.  The world's most complete source of free celestial navigation information.

• Astronomical Applications Department - The Astronomical Applications Department of the U.S. Naval Observatory computes, from fundamental astronomical reference data, the position, brightness, and other observable characteristics of celestial bodies, as well as the circumstances of astronomical phenomena.

• A Short Guide to Celestial Navigation - Henning Umland's Homepage.

• Navigator Software - Collection of celestial navigation resources.

  • • Online Nautical Almanac Data

    • Online Star Finder

• Stellarium web - Excellent Interactive Planetarium Online.

• Fourmilab Switzerland - Astronomy and Space resources:

  • • Earth and Moon Viewer

    • Orbits in Strongly Curved Spacetime

    • Solar System Live

    • Your Sky

    • Calendar Converter

• In The Sky - Guides to the night sky by Dominic Ford. A website to what's visible in the night sky, which automatically tailors information to wherever you happen to live on Earth with excellent tools and resources:

  • • Planetarium

    • Sky Charts

    • and  more...

• Celestial Navigation - This webpage is an attempt to bring together all of the best Celestial Navigation resources on the internet.

• BackBearing - Celestial Navigation website. All you need to navigate by the Sun.

• Erik's nautical website - Website supplying all the information needed for Celestial Navigation (Nautical Almanac, Interpolation Tables, Sextant Correction Tables, Sight Reduction Tables, Worksheets and Instructions) from a single source in a complete and consistent form.

• Astro Navigation Demystified - This is an excellent website promoting a book of the same title. Highly recommended for the clear, concise explanations.

• Rodamedia - Sitio web personal de Luis Mederos, con una variedad de contenidos relacionados con la navegación, tanto de altura como de cabotaje. Incluye un listado de los libros publicados por el autor, así como acceso a los videos divulgativos disponibles en su canal de YouTube.

• Navigational Algorithms - Website of Andrés Ruiz González, featuring a variety of content created by the author, including books, manuals, and software for WindowsOS and AndroidOS.

OTHER LINKS OF INTEREST

• Maritime Safety Information - NAVIGATIONAL WARNINGS: Broadcast Warnings are promulgated by the Worldwide Navigational Warnings Service (WWNWS) to provide rapid dissemination of information critical to navigation and the safety of life at sea. 

• Naval Oceanographic Portal - The United States Naval Meteorology and Oceanography Command (NMOC) provides critical information from the ocean depths to the most distant reaches of space, meeting needs in the military, scientific, and civilian communities. 

• Digital Nautical Chart - The Digital Nautical Chart (DNC) is produced by the National Geospatial-Intelligence Agency (NGA) and is a vector-based digital product containing maritime significant features essential for safe marine navigation. DNC, for areas in which the US is the prime charting authority, is unclassified. All other areas are limited distribution.

• UK Hydrographic Office - The UK Hydrographic Office (UKHO) is a world-leading centre for hydrography, specialising in marine geospatial data that helps others to unlock a deeper understanding of the world's oceans.

• IMO International Maritime Organization  - Global Integrated Shipping Information System: Public Area.

• Survivor Library - The library contains thousands of  books on technologies that can be produced by most reasonably skilled craftsman using tools not as sophisticated as what can be found in many modern home workshops.

• Internet Archive - The Internet Archive, a nonprofit organization, is building a digital library of Internet sites and other cultural artifacts in digital form. Like a paper library, it offers free access to the general public. Its mission is to provide universal access to all knowledge.

• NavList - NavList is a community devoted to the preservation and practice of celestial navigation and other methods of traditional position-finding or with techniques which are non-electronic.

• Revista Timoneles - Revista didáctica, con artículos de investigación, actualidad, viajes, competencias náuticas, pesca, turismo y notas técnicas, para fomentar el desarrollo y la divulgación de cualquier actividad relacionada con la náutica deportiva.