Galaxy

Galaxy places a spiral galaxy around an object: a warm glowing bulge at the centre, two trailing arms traced by young blue stars, dark dust lanes along their inner edges and pink knots of glowing gas strung along the arms. Thousands of stars turn slowly, and the arms keep their shape as they do.

How it works

The arms are not fixed bands of stars. Every star moves on its own oval orbit, and each orbit is turned a little more than the one inside it. Where the turned ovals crowd together, stars are packed more densely, and those crowded strips form the spiral arms. The stars keep moving through the arms while the pattern itself turns slowly, which is how astronomers explain real spiral galaxies. Young, hot stars only appear in the arms, so blue light traces them, while old stars spread smoothly and glow warm.

Settings

• Star Count: from two thousand to forty thousand stars.
• Arm Twist: how tightly the arms wind; 0 gives a barred oval.
• Ellipticity: how stretched the orbits are; higher gives stronger arms.
• Bulge Size: the size of the central glow.
• Dust: how dark the dust lanes are.
• Tilt: the angle of the disk.
• Color (young arm stars) and Core Color (old bulge stars).

Use it for

Space and astronomy scenes, sci-fi backdrops, cosmic hero sections, science explainers. Pair it with a Black Hole at the centre or with Stars.