Fireworks Simulator (2D) | mysimulator.uk

Launch

Launch power 70%

Shell type

Metal salt / color

Click the sky or press Launch to fire a shell.

Live Readout

Particles aloft

Last apex height

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Shells fired

Muzzle velocity

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How it works

A shell leaves the mortar with muzzle velocity v₀ set by launch power, then follows real projectile motion under gravity (g = 9.8 m/s²): height climbs as v₀t − ½gt², so a harder launch reaches a higher, later apex. A time-fused burst charge fires close to the top of that arc, which is why real shells appear to hang for a moment before exploding.

At burst, dozens of glowing "stars" are thrown outward at their own speed and then become independent projectiles themselves — each one decelerated by gravity and air drag, which is why a sphere of sparks droops into a falling dome rather than staying perfectly round. Willow stars burn slow and low-velocity so they hang and trail; chrysanthemum stars leave a visible spark trail as they fly; a crossette star splits into a small secondary burst partway through its fall; a ring shell constrains the stars to a flat disc instead of a sphere.

Color comes from the metal salt packed into each star: strontium salts burn red, calcium orange, sodium yellow (the same emission line as a sodium streetlamp), barium green, copper chloride blue, potassium violet, and a titanium/magnesium alloy burns silver-white without a bright emission line — the same flame-test chemistry used in Flame Test Colors, applied here to a whole shell instead of a single ion.

Click the sky to launch a shell there