What's under the hood
Platforms, distribution formats, data sources, and system requirements.
Platforms & formats
| System | Format | Standard edition | Pro edition |
|---|---|---|---|
| Windows 10 / 11 | .exe (installer) | 108 MB | 115 MB |
| Linux (any distribution) | .AppImage | 117 MB | 124 MB |
| Linux (Debian / Ubuntu…) | .deb | 109 MB | 113 MB |
| Linux (Fedora / openSUSE…) | .rpm untested | 114 MB | 119 MB |
The .rpm package is provided but its installation has not been tested by the author — see the FAQ.
Data sources
| Domain | Source | Licence |
|---|---|---|
| Planetary ephemerides | ANISE (Nyx Space) / JPL DE (NASA-JPL) | MPL-2.0 / public domain |
| Stars & constellations | d3-celestial / Stellarium — 88 IAU figures | BSD |
| Worldwide tides Pro | TICON-4 (DGFI-TUM, GESLA-4) via the Neaps database — 4,170 stations | CC BY 4.0 |
| Magnetic variation Pro | WMM — World Magnetic Model | public domain |
| Basemap | Natural Earth | public domain |
Background stars and constellation lines are shown in simplified geometric position (no refraction or dip); the Sun, Moon, planets and navigation-star catalog use the software's usual precise positions.
GPS connectivity Pro
Serial port
Wired NMEA 0183.
UDP network
NMEA 0183 via multiplexer.
NMEA 2000
Fast-packet frames (PGN).
SignalK
WebSocket, SignalK deltas.
A built-in GPS simulator can emit these same protocols (UDP NMEA 0183, NMEA 2000, SignalK/WebSocket) to test reception without any connected hardware.
Full Standard / Pro comparison
| Feature | Standard | Pro |
|---|---|---|
| Ephemerides (Sun / Moon / planets / stars) | ✓ | ✓ |
| Observed fix (sight reduction, Polaris, meridian passage, body ID) | ✓ | ✓ |
| Dead reckoning | ✓ | ✓ |
| Route — rhumb-line / great-circle / composite | ✓ | ✓ |
| Lines of position + SHA-256 chained logbook | ✓ | ✓ |
| Error budget | ✓ | ✓ |
| Paper reduction worksheet + backup almanac | ✓ | ✓ |
| Compass check (azimuth / amplitude) | ✓ | ✓ |
| Conversions, Definitions, solar eclipse | ✓ | ✓ |
| Printable manual, session autosave | ✓ | ✓ |
| GPS reception (serial / UDP / NMEA 2000 / SignalK) + simulator | — | ✓ |
| Worldwide offline tides (4,170 stations) | — | ✓ |
| Plotting sheet (secant Mercator) + world map | — | ✓ |
| Man overboard (MOB) with staleness check | — | ✓ |
| Compass deviation — full table and curve | — | ✓ |
| WMM cross-check (magnetic variation) | — | ✓ |
| Enhanced visual theme (egui-phosphor icons) | — | ✓ |
Language & design
Written in Rust
A native application, with no external runtime dependency and no internet connection needed to run.
Automatic autosave
The session (positions, observations, settings) is saved automatically as you work.
Self-test panel
An internal validation panel, reachable from the Help tab, lets you check the consistency of the calculations.