but what happens to the old ones?

Space is getting crowded...

so we'll show you what the law says about who is responsible

and what happens if things start crashing into each other.

Is space junk putting our way of life at risk?

And what happened when NASA's Skylab fell from the sky...

The European Space Agency estimates there are currently

170 million bits of rubbish orbiting the Earth.

How did they get there?

And could they be a more serious problem than you think?

Space travel is not something to take for granted.

It could actually become impossible,

dramatically impacting our daily lives.

In 1978, NASA scientist Donald J Kessler predicted

that as we keep launching things into orbit,

more and more of them could hit each other,

breaking up into smaller bits.

Those bits hit other objects and break again...

...and again.

Eventually, the amount of space debris

could make it unsafe for any space travel –

or even satellites for things like GPS,

television, or weather forecasts.

This is called the Kessler syndrome.

Professor Moriba Jah is taking this very seriously.

His map tracks all known human-made objects in space

to help scientists monitor and predict their behaviour.

This is what I call a super-spreader event:

large rocket bodies that have been up there for decades,

that are pretty much ticking time-bombs

and that at some point, they will either explode

or something will hit them

and they'll become many tens of thousands of pieces.

The map is tracking 200 potential 'super-spreader events'.

These rocket bodies belong to at least three different countries.

So, with the danger of satellites crashing increasing,

here's space lawyer Jessica Noble

to explain what that means and who is responsible.

Right now, if...

if a satellite crashes into another...

another object, whether that is in space or on Earth,

the state that launched that satellite is the one

who is responsible for that damage and for any clean-up.

However, right now there are no explicit laws

regarding removal of debris or dead satellites in orbit.

However, there have been norms and guidelines

that states have been working on to address that very issue.

When a country launches a satellite, it is responsible for it

and any damage it might cause,

though the law does not fully address this issue yet.

What about the environment in space?

Does the law protect it from damage?

In the Outer Space Treaty, one of the articles addresses

protection of the outer space environment

and requires that states conducting activities

in outer space do so in a manner

which avoids harmful contamination of the...

the moon and other celestial bodies.

However, this term 'harmful contamination' is not really...

is not well understood at this point.

We don't know exactly what that means,

as it relates to conducting activities in outer space

and that's something that we're...

there we're trying to figure out right now.

The Outer Space Treaty, one of the oldest bits of international space law,

was created to protect the space environment,

but it's not exactly clear on what it means about pollution.

So, has the situation changed since the treaty was written?

Is it still good enough?

The treaty might have come about in 1967,

but the authors of the treaty did a good job

of leaving the language broad enough

to account for different types of activities in space.

It is still the backbone of all of our activities

around the globe, in space,

and has provided a good platform for those activities.

There's always room for... for change

when we think about norms

or how we approach those activities,

but the treaty itself as the foundational law

is still relevant and still applicable today.

Jessica's opinion is that the Outer Space Treaty was written in a way

that makes it flexible enough to cope with all the changes

and the new problems we face in space.

So, laws make it clear who's responsible for crashes,

but there's still work to be done on pollution.

But what happens when something falls out of orbit...

...and down to Earth?

That's exactly what happened to the US space laboratory Skylab.

At the end of its life in 1979,

it was supposed to break apart and fall into the sea.

That didn't go to plan.

Most of it did end up in the Indian Ocean,

but some, including this bit, landed in Western Australia.

No one was hurt, luckily, but what laws dealt with this?

Has the law changed since then?

The law regarding damages from...

from space to Earth is contained in the liability convention.

And that convention – that was a treaty that came into force in 1972

and that is still the same today.

It... it relates to...

it deals with space objects hitting the Earth

and it deals with space objects hitting each other up in space.

But there's a different type of liability

that applies in space to one that applies on Earth.

A law called the Liability Convention of 1972

still deals with space objects hitting the Earth,

so the law hasn't changed since Skylab crashed.

So, if something hit my house, what could I do?

The law does permit you to sue what's known as the launching state,

who is responsible for that piece of space junk

that crashed into a house or landed on your property,

if... if you incur damage.

If you have damage as a result – that's....

that's physical injury or damage to property –

then you have a right to claim compensation for that damage.

And you can do it in one of two ways:

you can have your country, your state,

make a claim against that other state who was responsible for that damage;

or you can go to that state's own courts

and you can make a claim yourself.

But you cannot do both at the same time.

If your house gets hit by something from space,

you can claim damages in one of two ways:

either through your own government or via the other country's courts.

So, what about protecting the environment

from crashes and accidents?

Many states require you to get a licence,

to provide them with an environmental protection plan.

They need to see what you're going to do,

with respect to protecting the environment,

before they issue you with a licence.

So, in that regard states

and their domestic national concerns

are ahead of the game, regarding international law,

which doesn't impose those same requirements.

Yet, because of that though, I think it's only a matter of time

before these environmental controls that are imposed nationally

will find international expression

and be part of international law.

Some countries require that you have a licence to launch a spacecraft.

To get this, you need an environmental protection plan,

but there isn't an international law about this yet.

The law tries to keep our satellites and spacecraft safe from junk,

and tries to protect us, here on Earth.

But it's clear there's still work to be done for lawyers!