made of platinum or gold,

contains a secret

that has been at the center

of a cosmic mystery.

Scientists have been combing the galaxy

to figure out

where these so-called

heavy elements come from.

Lighter elements, everything from helium

with its two protons

per atom on up to iron,

which has 26 protons in each nucleus,

are better understood.

Most of these form inside stars,

but our knowledge gets fuzzy after iron.

Gold, which has 79 protons

in each atom, can't be made that way.

The same goes for platinum, xenon,

radon and many rare earth elements.

For decades, scientists theorized

where these heavy metals come from

and how they arrived on Earth.

The leading idea

was an extremely violent, cosmic event,

a collision between two neutron stars.

Until recently, this was just a theory.

But that changed a few years ago,

when scientists detected

gravitational waves from such a crash

and saw light at the same time.

This light held the

chemical signatures

of these heavy elements,

offering the first evidence,

supporting the theory

of where they come from.

It also helped scientists

fill in some of the details

of how this process might work.

Neutron

stars are the densest things

in the universe except for black holes.

They are born

when heavy stars die

in their cores collapse.

The incredible gravitational pressures

pushes the atoms together.

Protons and electrons push

all, leaving a star

almost entirely made of neutrons.

In the rare case,

when two neutron stars slam together,

the explosion creates

mind blowing temperatures and pressures.

It also pumps out a lot of free neutrons.

Up to a gram of neutrons

spills into every cubic centimeter

of space.

These rare conditions

ignite what's called the rapid

neutron capture process,

otherwise known as r-process for short.

It all

starts with a seed nucleus such as iron.

The iron nucleus starts out

with 26 protons and around 30 neutrons.

But during the r-process,

it will quickly capture

many more neutrons

in a matter of milliseconds.

The new nucleus is highly unstable

because of its lopsided

quantity of neutrons,

so some of those neutrons

will decay into protons.

The result of this extremely fast,

complex process is a new form of matter.

Just think that piece of gold

on your finger.

Every bit of it

started off in a cosmic cataclysm

that is among the most violent

and powerful forces in the universe.

A cosmic mystery

on the way to being solved

and a piece of the universe all in

the palm of your hand.