Popular Science - USA (2019-10)

POPSCI.COM•WINTER 2019 19

Saturn V rocket Chelyabinsk meteor

Actual

Measurement

90 dBfrom

435 miles away

Actual Measurement

204 dB

Calculated

Measurement

180 db from

3 miles away

would do far worse than make you wince.
Events on the scale of volcanic eruptions and
exploding meteorites register at more than
194 decibels, a level that generates enough
force to potentially pierce your eardrums and

pop your lungs. At those highs, sound waves

are so powerful, they no longer slip through the

air but rather shove molecules out of their way.

Decibels can’t even accurately measure these

bangs; researchers instead quantify them by the

amount of energy they release—like they do for

bombs or other explosives. Here are some of

the most deafening things on Earth, both natu-

ral and mechanical, including the absolute

biggest kabooms ever recorded.

Tunguska meteor

Actual

Measurement

N/A, but

registered on

barometers as

far as England

Calculated

Measurement

197 dB from

3 miles away

Krakatoa

Actual

Measurement

172 dB from

100 miles away

Calculated

Measurement

189 to

202 dB from

3 miles away

When Krakatoa erupted

in 1893, it obliter-

ated more than half of

the island’s landmass,

created 100-foot-tall

tsunamis, and deafened

anyone it didn’t kill

for miles around. The

death toll was over

36,000. Zanzibar

beachgoers discovered

washed-up human skele-

tons melted onto slabs

of pumice as long as

nine months afterward.

Even thousands of

miles away, in New

Guinea and parts of

Australia, the blast

was said to sound like

gunfire. Its total

power amounted to

200 megatons of TNT,

or 13,000 Little Boy

atomic bombs.

One June morning in

1908, a shock wave

knocked a Siberian man

out of his seat on the

front porch. The Tun-

guska meteorite was to

blame. It had burst in

midair 40 miles away

with a blast equiva-

lent to 650 Hiroshima

bombs. Eyewitnesses

said the shattering

space rock rang like

artillery fire from

that distance and was

as bright as the sun.

There’s no evidence

of any fatalities,

but the meteorite

flattened at least

600 square miles of

forest, leaving

80 million felled

trees to rest in a

radial pattern.

Type “Chelyabinsk

meteor” into YouTube,

and you can experience

this explosion for

yourself. A handful

of Russian dashboard

cameras caught it on

tape. A force equal to

500 kilotons of TNT

shattered glass and

tossed debris through-

out the city, injuring

more than 1,000 peo-

ple. Big booms

typically emit a lot

of far-reaching ruckus

called infrasound,

which is too low-

frequency for human

ears to pick up.

Chelyabinsk was no

exception, with deep

tones hitting sensors

9,000 miles away in

Antarctica.

Developed for the

Apollo program, NASA’s

Saturn V rocket is a

decorated record-

holder. It is the

tallest and most

powerful spacecraft

to successfully fly.

The behemoth has

launched 13 times,

propelling 260,

pounds of payload into

orbit on each go. A

portion of the rocket

called the SI-C stage

generates around

7.5 million pounds of

thrust to do so. All

that power translates

into quite a bit of

noise, which NASA

dampens by dousing the

launch area in cur-

tains of water to

absorb pressure waves.