Orrery

A live solar system as your wallpaper. Every planet sits where it really is, and the spacecraft of the space age fly the paths they really flew. It's all drawn on pure black for OLED screens.

The project page shows it moving: up close, from afar, and everything between.

Also on Android, as an app, a live wallpaper and a screensaver: Orrery for Android.

What it does

An orrery is the old clockwork model of the solar system. This one runs on real astronomy. The planets follow NASA JPL's orbits and turn the way they really face, so Earth's day side matches the time on screen. Over a hundred spacecraft and telescopes, from Mariner 2 in 1962 and the Apollo flights to Dragonfly on its way to Titan, follow paths fitted to JPL's record of where they went. The ones still flying follow their published plans.

Leave it running and it shows the solar system right now. Or play with it:

• Click anything for a card of live facts. It shows how far away it is, how long its light and radio take to reach us, what the trip would take, and trivia about each world.
• Double-click a planet to fly in to its moons, satellites and landers.
• Scroll out past the Voyagers to the heliopause, the Oort cloud and the nearest stars.
• Drag the timeline through sixty years of launches and flybys, and on to the missions still to come.

Up close

Double-click a planet, scroll the wheel over it, or press the zoom button on its card. The planet fills the screen, with its moons where they really are and the satellites and spacecraft circling it.

From afar

Scroll down on the desktop to pull back. You pass Neptune and the Kuiper belt, the termination shock and the heliopause, and rings for a light-day, a light-month and a light-year. Then come the Oort cloud's trillions of comets, and Alpha Centauri. The Voyagers, the Pioneers and New Horizons fly out along dashed paths marked with the years they get there, out to 40,000 AD.

Everywhere on the desktop

The Activities overview and workspace switches show the solar system, still moving. The timeline's buttons pause and play, change the speed, stop the spin, play music, show and hide things, and open the settings.

Everything, in detail

• Real positions. Planets sit where they really were (or are) on the date shown, from NASA JPL's orbital elements (good from 1800 to 2050).
• 3D look. You see the system from an angle. Each planet is a lit sphere with a sharp day/night line, turning on its real axis: Uranus rolls on its side, and Saturn's rings tilt the way they really do.
• Relative speeds. Planets orbit at their true relative speeds. They also spin at their true speeds relative to each other, on a slower clock so Jupiter's 10-hour day does not blur.
• The space age, replayed, and what is coming.
  • Flown: 21 spacecraft fly the gravity assists they really flew, on the real dates: Mariner 10, Pioneer 10 and 11, both Voyagers, Giotto, Galileo, Ulysses, Cassini, Rosetta, MESSENGER, New Horizons, Dawn, Juno, Hayabusa2, OSIRIS-REx/APEX, Parker Solar Probe, BepiColombo, Solar Orbiter, DART and Lucy.
  • Orbiters, landers and comet chasers: 35 more, from Mariner 2, the Veneras and the Vikings to Magellan, NEAR, Stardust, Deep Impact, the Mars rovers, MRO, MAVEN, Hope, Tianwen-1 and Perseverance, on paths fitted to JPL Horizons.
  • To the Moon: 29 missions, from Luna 9 and Apollo 8 to Chang'e 6, Blue Ghost and Artemis II. They fly in Earth's close-up: free returns around the far side, lunar orbits, landings and liftoffs, CAPSTONE's halo orbit and the long looping routes of GRAIL, Danuri and SLIM.
  • Planned: missions on their way fly their planned routes into the 2030s: Psyche, Juice, Europa Clipper, Hera, Tianwen-2, ESCAPADE, MMX and Dragonfly.
  • At L1 and L2: telescopes and Sun-watchers sit there: SOHO, WMAP, Herschel, Planck, Gaia, JWST, Euclid, Aditya-L1, IMAP, Roman and PLATO.
  • A card pops up at each launch, flyby and arrival.
• Stories and tours.
  • Press ▶ Story on a mission's card to follow only that spacecraft from launch to the end. It cruises between encounters, flies in to each planet it passes to watch the swing-by up close, and heads out past the planets with the Voyagers. A bar at the top steps back and forward or exits.
  • The panel's Tours fly past every planet in turn, or play every mission's story one after another.
  • Automatic tour (in the preferences) starts planet flybys, every story, or one mission's story after the desktop has sat untouched for a few minutes, and stops as soon as you're back.
• Moons, asteroids, comets and Lagrange points.
  • The 22 biggest moons circle their planets on a squeezed scale (our Moon where it really is, at its real phase).

Status

Stable: v1.4.0 is the latest release.

• GNOME: tested in a real GNOME Shell on 48, 49, 50 and 51, each in a container, both from source and from the installed RPM and DEB packages.
• Other desktops: the orrery-wallpaper companion's live background is tested in Sway, and its pictures render on Fedora, Debian and Arch.
• Mission dates: dates after today are the published plans, and may change.

Planned

Orrery on macOS and Windows, as a web wallpaper. The orbits, missions and fact cards are plain JavaScript, so they can run in a browser. A small layer will let the same drawing code paint on a web canvas as well as in GNOME. The plan, in order:

1. A web build of what orrery-wallpaper shows: the solar system moving, without the clicking.
2. Packages for wallpaper apps that show web pages: Lively Wallpaper on Windows and Plash on macOS. The same build will run live on the project page.
3. The cards, the timeline and flying in and out, rebuilt in HTML.

The GNOME extension stays the main version, and both will share the same astronomy and mission code.

Install

From the latest release. Orrery runs on GNOME 48, 49, 50 and 51.

v=1.4.0   # the release's version
url=https://github.com/fqazzazee/orrery/releases/download/v$v
# Fedora, RHEL, openSUSE (zypper install works the same)
sudo dnf install $url/gnome-shell-extension-orrery-$v-1.noarch.rpm
# Debian 13+, Ubuntu 25.04+, Pop!_OS, Mint
curl -LO $url/gnome-shell-extension-orrery_${v}-1_all.deb
sudo apt install ./gnome-shell-extension-orrery_${v}-1_all.deb
# Arch, Manjaro, EndeavourOS
curl -LO $url/gnome-shell-extension-orrery-$v-1-any.pkg.tar.zst
sudo pacman -U gnome-shell-extension-orrery-$v-1-any.pkg.tar.zst
# Any distribution, just for you
curl -LO $url/[email protected]
gnome-extensions install [email protected]

Log out and back in, then turn on Orrery in Extensions (or gnome-extensions enable [email protected]). Settings are in the extension's preferences, or behind the gear on the timeline.

Each release lists its files' SHA-256 sums in SHA256SUMS. With it beside your downloads, sha256sum -c --ignore-missing SHA256SUMS checks them.

From a checkout, make link symlinks it into ~/.local/share/gnome-shell/extensions.

The scene covers the main monitor. The others get a solar system of their own (starting at the same date, and explored separately), a copy of the main one, or the plain wallpaper, under Content › Interaction › Other monitors. The overview and workspace switches show live copies of them. If you would rather see your wallpaper there, turn that off under Content › Interaction.

Clicks reach the scene wherever no window covers the desktop. A desktop-icons extension draws a window over the whole desktop, which takes those clicks instead.

Other desktops

GNOME Shell extensions only run in GNOME Shell. For KDE Plasma, XFCE, Cinnamon, MATE, Budgie, LXQt, Sway, Hyprland and the rest, there is orrery-wallpaper, in the same three package formats. It draws the same solar system, without the clicking.

• A wallpaper that keeps up: systemctl --user enable --now orrery-wallpaper keeps the wallpaper showing the solar system as it is right now, redrawn every 10 minutes.
  • It is set with your desktop's own tool: plasma-apply-wallpaperimage, xfconf-query, gsettings, swaymsg, hyprpaper, swaybg or feh.
  • Some desktops do not start systemd's graphical session (XFCE, MATE, LXQt). There, copy /usr/share/orrery-wallpaper/autostart/orrery-wallpaper.desktop to ~/.config/autostart/ instead.
• An animated background: systemctl --user enable --now orrery-wallpaper-live runs one on Wayland compositors with layer-shell (Sway, Hyprland, niri, labwc, river, Wayfire, COSMIC). It needs gtk4-layer-shell.
• One picture: orrery-wallpaper render picture.png [--date 1989-08-25] [--size 3840x2160] draws it. orrery-wallpaper --help lists the rest.

Android

Orrery for Android brings the same solar system, missions and cards to phones and tablets, with a touch interface: tap for a card, double-tap a planet to fly in, pinch out to the Oort cloud. It runs as an app, a live wallpaper for the home and lock screens, and a screensaver while charging.

Download the APK from its latest release and open it on the phone. It needs Android 8 or later, is about 300 KB, and asks for no permissions.

Power and OLED care

• Stops when hidden: with Background only animation (the default), it stops whenever maximized or fullscreen windows or the overview hide the desktop. Continuous keeps it going behind windows, and Paused keeps a still picture that only moves while the pointer is on the desktop. The panel on the timeline switches between the three. Nothing runs behind the lock screen.
• See-through apps: pick apps, like a transparent terminal, and choose what carries on behind their windows: the animation, the music, or both.
• Several monitors: it only stops once every monitor showing the solar system is hidden.
• Little redrawing:
  • Planets move by translation, not relayout.
  • Each layer only redraws when it changes by most of a pixel.
  • The bands on Jupiter and Saturn are drawn once and reused.
• True black: night sides, glows and cards all fade to #000000.
• Pixel shift slowly drifts the whole scene by a few pixels to spread wear.
• Pause once windows cover a set share of the desktop, not only when one is maximized.
• Battery saver: on battery or in Power Saver mode, the frame rate drops and the planets stop spinning.
• Slow down when still: with time paused and nothing spinning, it runs at 5 frames per second until the pointer moves.
• Dim after a few idle minutes: the scene fades to a lower brightness and 10 frames per second. It comes back the moment you move the mouse.
• Quiet timeline: it only lights up while you use it.
• Save more by lowering Frames per second and Brightness.

How the paths are built

Lambert legs. Each leg between two encounters is the orbit that joins the two bodies' real positions on those dates (Lambert's problem). The path is exact at every encounter.

Waypoints. Some craft fired their engines between encounters: the ion-driven Dawn, Psyche and BepiColombo, or long loops like Ulysses's. For them, waypoints from NASA JPL's Horizons trajectories keep the path to the one the craft really flew. tools/fit-waypoints.py compares every mission with Horizons. It adds waypoints until the model stays within 4% of the distance from the Sun.

Resonant loops. Some legs leave a planet and return to it after a whole number of its years, like Parker's Venus loops and Galileo's two-year loop. Any orbit with a matching period would fit these, so they use the craft's known number of laps and its perihelion instead.

Leaving the planets. The Pioneers and Voyagers head out in their real directions at their real speeds.

Squeezed distances. Distances are compressed (square root by default) so that Mercury and Neptune fit on one screen.

Development

make test                    # unit tests for the orbital math, every mission path and every card (gjs only)
make test-shell RELEASE=45   # run it in a real GNOME Shell 51 in a container (44: GNOME 50, 43: 49;
                             #   DISTRO=debian RELEASE=trixie: 48), and report any JavaScript error
make dist                    # build the zip and the rpm, deb and Arch packages into dist/ (podman or docker)
tools/fit-waypoints.py [id]  # refit mission waypoints against JPL Horizons (needs network)

To release, push a tag like v1.4.0 that matches version-name in metadata.json. GitHub Actions then builds every package and publishes them as a release.

The project page lives in docs/. Its screenshots and clips were recorded from the extension itself, running in a headless GNOME Shell.

Contributing

Bug reports and ideas are welcome in issues. If you want to add a mission, open an issue first, with its JPL Horizons ID if it has one.

Support

If it made you look up from your work and wonder where Voyager is now, you can buy me a coffee ☕.

License

Orrery is free software under the GPL-2.0-or-later (LICENSE), as GNOME Shell's own license asks of its extensions.

The planets' orbits come from NASA JPL's approximate orbital elements. The asteroid and comet orbits come from JPL's Small-Body Database. The spacecraft paths are checked against JPL Horizons.