bang-bang
OVERVIEW
EVEN THE MOST
elaborate fireworks show starts
with a single crack, as black
powder shoots shell from
mortar. That launch sets off a
cascade of whooshes, zips, and
bangs that send colorful shapes
soaring into the sky. Here’s how
engineers can tweak these pyro-
technics to provide spectators
with stunning displays.
LIGHT
Fireworks have followed
the same basic format
for centuries: As a fuse
inside a sky-bound shell
burns down, it ignites a
series of explosive
charges. Little pellets
called “stars” sit in clus-
ters between them and
burst aflame as they fly
out into the air.COLOR
“White fire” ruled the
skies until the 1800s,
when engineers first
added metals and salts to
their mixtures to create
a rainbow of hues.
Strontium (red), alumi-
num (white), and copper
(blue) are common
components.SOUND
Want your show to really
pop? Tightly cramming
chemicals into tubes
makes a sharp whistle as
gases squeeze out like
steam from a kettle.
Drilling tiny exhaust holes
on the sides of a snugly
sealed charge creates a
delightful, buzzy hum as
the apparatus spins.22 WINTER 2019 • POPSCI.COM by Kat Eschner / illustrations by Alessandro Rustighi