Leave the ground
Most sky viewers keep you standing on the ground, looking up. Voyage lets you leave it. You fly out and look back, so the sky stops being a flat dome and becomes what it really is: worlds at real distances, floating in a lot of dark space.
Take the controls and fly the real solar system: the Sun, the planets and their moons at the positions Astronomy Engine computes for right now, the asteroid belt drawn at its true distance, and Saturn's rings at their real tilt. Tap any world to fly straight to it. Sizes are enlarged by default so distant worlds stay findable; switch to true scale to feel how empty the real solar system is.
What is real here, and what is not
Voyage is a planetarium show you can pilot, not a measurement. Flying is a way to feel scale, never a claim that a spacecraft is really at some position. The planets, their moons, and Pluto sit at the positions the open-source Astronomy Engine computes for right now, and Saturn's rings use their real extent and tilt. The asteroid belt is drawn at its real distance range, but it is an illustrative density: the real belt is mostly empty, with its asteroids roughly a million kilometers apart. The background stars are shown at their true directions, the way a star chart shows them, not at their true distances. For measured positions of the sky tonight, use the sky map, the Today in the Sky page, or the live orrery.
Questions about Voyage
Am I really flying through space?
No. Voyage is a planetarium show you can pilot, not a real journey. Flying is a way to feel the scale of the distances between the worlds. The positions of the Sun, planets, and moons are real, computed in your browser for the current date, but the flight itself is a model.
Are the planet and moon positions real?
Yes. The Sun, the eight planets, the Moon, Pluto, and Jupiter's four large moons are placed at the positions the open-source Astronomy Engine computes for the current date, the same engine the rest of the site uses. Saturn's rings use their real extent and tilt.
Why are the planets enlarged, and what does true scale show?
At their true size the planets are almost invisible dots against the distances between them, so by default Voyage enlarges distant worlds enough to see them and fly to them. Switch to true scale from the toolbar to see how empty the real solar system actually is.
Is the asteroid belt real?
The belt is drawn at its real distance range, from about 2.1 to 3.3 astronomical units, but its density is illustrative rather than a count of individually measured asteroids. The real belt is mostly empty space, with its asteroids roughly a million kilometers apart, so a pilot would rarely see one up close.
How do I fly it?
Press Take the controls, then steer with your mouse or the A and D keys, set your throttle with W and S, boost with Shift, and stop with the spacebar. Tap any world to fly straight to it, or use the Fly to menu. Press V to switch between the chase view and the cockpit, and Escape to step back out.
Keep exploring the real sky
Every world you fly to in Voyage has a measured home elsewhere on the site. Tap a world in flight to open its card, then follow the links, or pick up the thread here:
- Live orreryWatch the planets circle the Sun in real time, from above.
- Today in the SkyWhat is up over you right now, with rise and set times.
- Sky MapThe measured night sky from your exact spot on the ground.
- Planet conjunctionsWhen two worlds meet, including the great Jupiter and Saturn pairings.
- Planet paradesWhen several planets line up across the sky at once.
- Eclipse explorerEvery solar and lunar eclipse for your lifetime.
- Why Earth has seasonsThe tilt that drives the year, shown two ways.
- Retrograde motionWhy Mars and the outer planets seem to loop backward.
- Moon phase calendarThis month's phases, and the next full and new Moon.
- Telescope and eyepieceWork out what your own gear can actually show you.