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Would you sleep in this earthquake-proof bed?
It senses when an earthquake is happening
and drops you into a safe, metal chamber.
Yeah, we know how ridiculous this looks.
But desperate times
call for desperate measures.
Because we're about to experience
the most powerful earthquake in history,
a magnitude 20.
To understand just how big
a magnitude 20 earthquake would be,
let's take a look at the Richter scale.
The Richter scale is a logarithmic scale
that rates the amount of energy
released by an earthquake.
What does "logarithmic" mean?
In this case,
it means that the amount of energy released
increases 31.7 times
between whole number values on the scale.
For example, a 2.0 quake
is 32 times as energetic as a 1.0 event.
And a 3.0 quake
is 1,000 times more powerful
than a 1.0 event.
The largest earthquake ever recorded
registered a magnitude of 9.5,
and it caused about
five billion dollars in damage.
It killed 1,655 people
and left two million people homeless.
So how much worse would a magnitude 20 be?
Would we have to evacuate the planet?
To properly prepare for an
earthquake this big,
we need to understand what causes
earthquakes in general.
Earthquakes are vibrations that travel through
the crust of the Earth.
They can be caused by events like
volcanic eruptions
and meteor impacts
but the movement of tectonic plates
is what usually causes them.
These plates, which make up the Earth's crust,
can slide against each other
at a region called the transform boundary.
When the plates move in different directions,
they can cause a break in the Earth's crust
called a fault line.
This is where most earthquakes take place.
The plates create friction
as they push together tightly,
and if there's enough friction,
they can become locked together
and stop sliding.
But the forces of the Earth will continue to
push against them
and increase the pent-up energy and pressure.
When the pressure builds up enough,
it will overcome the friction
and result in an intense and sudden shift.
This causes the vibration
we know as an earthquake.
And the longer the fault line,
the more massive the earthquake.
So how long of a fault line
would be required to produce
a magnitude 20 earthquake?
Well, let's put it this way.
To produce a magnitude 10.5 earthquake,
you'd need a fault length of about 80,000 km.
And given that the Earth's circumference
is only about 40,000 km,
that would be highly unlikely.
With all that considered,
a magnitude 20 earthquake
seems pretty impossible.
So there's nothing to worry about.
Oh, right, except for that.
One way that a magnitude 20
earthquake could occur would be
due to a massive asteroid impact.
An earthquake this large
would last longer than any earthquake
we have ever experienced.
You would feel the shaking for at least
five minutes, and aftershocks would go on
for hours.
Tsunamis and volcanic eruptions
would be taking place,
more earthquakes would likely be triggered
and the whole world would be falling apart,
literally.
For the power of this earthquake
to destroy the planet,
it would need to overcome something called
the “gravitational binding energy,”
which describes the minimum value
a spherical and uniform object needs to keep
together under the influence of gravity.
Now, we won't get into specific values here
because we don't want to make things
any more complicated, so we'll leave it at this,
we're screwed.
A magnitude 20 earthquake
would produce more than enough energy
to overcome the gravitational binding energy
and destroy our planet.
But the good news is
that we would likely see
the massive asteroid coming
and would have time to prepare
for everything that comes with it.
Would it be enough time to
get off the planet before it explodes?
Well, that's a story for another WHAT IF.