Games Like Orrery: Live Solar System Wallpaper

Not a video. A calculation.

Most animated wallpapers loop a rendered clip. This one solves the ephemeris every frame. Open it right now and Jupiter is at the longitude Jupiter is at, Mars shows the face Mars is showing, and the Moon is in tonight's phase. Leave it running for a year and it will still be right, because nothing was recorded.

The bodies

The sky behind them

Lock the camera onto any of them - the Andromeda Galaxy, the Orion Nebula, the Pleiades - and the view narrows until it fills the screen.

Surfaces from spacecraft, not from noise

Mercury, Venus, Earth, the Moon, Mars and the four giants wear re-projected NASA and USGS imagery, so the Great Red Spot, Valles Marineris and your own continents are where they really are. Saturn's rings follow a measured radial profile, which is why the Cassini division sits at 1.95 planet radii instead of at a guess. At noon UTC the Sun really is over Greenwich, and the test suite checks it.

Yours to point

It stays out of the way

Nothing leaves your machine

No telemetry, no account, no network at run time. Every position is computed locally from catalogue data installed with the program. Settings and logs live under %APPDATA%, never inside the install folder.

How accurate, exactly

The test suite scores every body against JPL Horizons vectors at epochs the fitting never saw. Worst case for a planet over 1900-2049 is Saturn at about 9 arcminutes - the accuracy limit of the JPL fit itself. Moons are harder: a single Kepler orbit frozen at J2000 puts Mimas 42% of its orbit radius out of place by 2026, so the elements are re-derived once a year and interpolated, which brings Mimas to 6% and every other moon under 2.5%. Distances and body radii are compressed - at true scale the inner planets would be invisible next to Neptune. Directions are not: conjunctions, orbital planes and inclinations are truthful.