What is I, Voyager?

I, Voyager is

  1. an open-source software planetarium
  2. a development platform for creating games and educational software in a realistic solar system.

It is designed to be improved, modified and extended by the community. I, Voyager runs on the open-source Godot Engine and primarily uses Godot’s easy-to-learn GDScript (similar to Python). It can be extended into an independent free-standing project (a game or other software product) using GDScript, C# or C++.

New! If you are interested in our future development, come see our official Roadmap!

What does I, Voyager cost?

I, Voyager is free to use and distribute under the permissive Apache License 2.0. Projects built with I, Voyager are owned by their creators. You can sell what you make. There are no royalties or fees.

How do I contribute to I, Voyager development?

Help us grow the community by following us on Twitter and Facebook. Exchange ideas and give and receive help on our Forum. Report bugs (here) and astronomical inaccuracies (here). To see where we are going and how you might help, visit our official Roadmap. Contribute to code via pull requests at our repositories: https://github.com/ivoyager.

How can I support this effort financially?

New! Please visit our GitHub Sponsors page! GitHub will match your contributions dollar for dollar throughout 2020! Become a Mercury Patron for $2 per month! Or, if you are a company, please consider sponsoring us as a Saturn or Jupiter Patron. Goal #1: Make I, Voyager into a non-profit entity! This will shield us from tax liability, allow us to apply for grants, and secure our existence as a collaborative open-source project into the future.

Where did I, Voyager come from?

Creator and lead programmer Charlie Whitfield stumbled into the Godot Engine in November, 2017. By December there were TestCubes orbiting bigger TestCubes orbiting one really big TestCube*. An image of Earth taken from 6.4 billion kilometers away (the Pale Blue Dot) inspired the name “I, Voyager.” It is a play on “Voyager 1” (the spacecraft that took that image) and in honor of the Voyager Program. I, Voyager became an open-source project on Carl Sagan’s birthday, November 9, 2019.

(* Godot devs, bring back the TestCube!)

Authors, credits and legal

I, Voyager would not be possible without public interest in space exploration – expressed via funding of government agencies such as NASA, NOAA and ESA, and the scientists and engineers they employ. I, Voyager also owes a special debt of gratitude to Godot Engine’s creators and contributors. I, Voyager is copyright (c) 2017-2020 Charlie Whitfield. For up-to-date lists of authors, credits, and license information, see files in our code repository here or follow these links:

  • AUTHORS.md – contributors to I, Voyager code and assets.
  • CREDITS.md – the people and organizations whose efforts made I, Voyager possible.
  • LICENSE.txt – the I, Voyager license.
  • 3RD_PARTY.txt – copyright and license information for 3rd-party assets distributed in I, Voyager.

A tour in screen captures:

I, Voyager screen capture of Jupiter and Io viewed from Europa.
Jupiter and Io viewed from Europa. We’ve hidden all interface here for one of the best views in the solar system.
Image of Jupiter embedded in the orbital paths of its many moons
Jupiter and the four Galilean moons – Io, Europa, Ganymede and Callisto – embedded in the orbital paths of many smaller moons.
I, Voyager screen capture of Saturn's rings and its close-orbiting moons.
Saturn’s rings and its close-orbiting moons.
I, Voyager screen capture of Uranus' moons from the "north". Uranus' 98° axial tilt puts the solar system almost directly to the south.
Uranus’ moons are an interesting cast of characters (literally). The planet’s 98° axial tilt puts the inner solar system almost directly to the south in this image.
I, Voyager screen capture of the solar system showing outer planets and Pluto on July 14, 2015, the day of New Horizon's Pluto flyby.
Here’s the solar system on July 14, 2015, the day of New Horizon’s flyby of the dwarf planet Pluto (♇). Not coincidentally, Pluto was near the plane of the ecliptic at this time.
I, Voyager screen capture of Pluto and Charon.
Pluto and its moon Charon to scale. Both are tidally locked so their facing sides never change. (Actually, our facing sides aren’t quite correct yet for tidally locked bodies. We could use some help with that.)
I, Voyager screen capture of Main Belt and Trojan asteroids from above.
Jupiter (♃) is the shepherd of the solar system. Shown here are 64,738 asteroids, the vast majority in the Main Belt (the ring inside Jupiter’s orbit) but quite a few in the two Trojan groups (the “lobes” 60° ahead of and 60° behind Jupiter). The Hildas are also evident in this image. I, Voyager has orbital data for >600,000 asteroids (numbered and multiposition) but can run with a reduced set filtered by magnitude.
I, Voyager screen capture of Main Belt and Trojan asteroids from the side.
Asteroids viewed from the side. We use the GPU to calculate asteroid positions; each asteroid is a shader vertex that knows its own orbital parameters.
Screen capture of I, Voyager Planetarium GUI. Individual elements are shown when mouse moves to the GUI's screen zone.
The Planetarium has an easy-to-use interface that is mostly hidden during use; individual elements show when the mouse moves to the relevant screen zone.
Screen capture of I, Voyager's Project Template GUI. It's a simple starting point on which to build a game.
The Project Template has a “starter” GUI intended for game development. I, Voyager provides various GUI widgets (a system navigator, date-time display, etc.) that can be arranged into panels or however you need for your own project.