Solar System & the Milky Way

Real orbital periods · scaled distances · the galactic helix

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Lower = more realistic, symmetric helix · higher = lap the galaxy faster
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What am I looking at?

The science behind the simulation.

Why are the planets on a flat plane?

~4.6 billion years ago the solar system was a huge rotating cloud of gas and dust. As gravity pulled it in, it spun faster (like a skater pulling their arms in) and countless collisions cancelled out the up-and-down motions — flattening it into a spinning disk, like pizza dough flung into a flat sheet.

The planets formed out of that disk, so they all still orbit in nearly the same plane today. That plane is called the ecliptic (the amber disk).

Why is that plane tilted ~60°?

The tilt between the ecliptic (amber) and the galactic plane (blue) is about 60° — and it's essentially a coincidence.

The galaxy is ~100,000 light-years across; the cloud-speck that became the Sun was about 1 light-year across. Its spin was set by local turbulence in that little patch of gas, not by the galaxy's overall rotation. So every star's disk ends up randomly tilted — ours just happened to land near 60°. Other star systems show no alignment with the galaxy either.

It has no special name; it's just "the inclination of the ecliptic to the galactic plane."

Not the same as "axial tilt"

Don't mix this up with axial tilt (obliquity) — Earth's 23.5° spin-axis tilt that causes the seasons. That's the angle of a planet's spin, a totally different thing from the 60° tilt of the whole orbital plane shown here.

Why do planets go in front of, then behind, the Sun?

The Sun is moving through the galaxy (the green arrow), so as each planet circles the Sun it spends half its orbit ahead of the Sun and half behind — tracing a helix. Seen at the steep 60° angle, that just looks like the planet crossing in front of and behind the Sun once per lap. It's plain orbiting, viewed edge-on.

Accurate helix vs the "vortex" myth

A viral video shows planets dragged behind the Sun in a comet-like cone. That's wrong — planets aren't towed along behind; they lead and lag the Sun equally. Use the Helix model toggle to compare the real helix with the myth.

About the scale

Orbital periods are real (Mercury 0.24 yr → Neptune 164.8 yr). The galaxy is roughly proportioned correctly (~100,000 light-years across, Sun ~halfway out). The solar system, though, is drawn millions of times too big so you can see it. The galaxy-orbit speed is sped up too (one real lap takes ~230 million years).

Flip on 🤯 True galactic scale in the Milky Way controls to shrink the solar system to its real size — a single speck on the orbit, about 55 million times smaller than its trip around the galaxy. The readout shows how many light-years your view spans.

drag to orbit · pinch or scroll to zoom