Space Junk 3D Page #2

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military and internet communications.

Because its orbit

mirrors earth's rotation,

a satellite will appear to hover

over a point on the earth's surface.

The result? 24/7 continuous

coverage from air to sea, to land...

Think about this:

Here on earth when you download

a music file, host a video,

tweet, friend someone, or watch

your favourite cable TV show,

it's coming from GEO.

Our busy lives on earth have

become deeply connected to space.

Just like a coral reef or a rainforest,

GEO is a limited natural resource.

There's only one spot in GEO for

each satellite to maintain position.

Satellites may drift due

to gravitational pull from

both the Sun and the Moon,

slowly changing their orbits.

Enter station keepers,

traffic cops of space...

They send signals commanding

satellites to adjust orbits,

by firing up the onboard thrusters,

keeping them out of harm's way.

But no amount of station keeping

would have altered the course

of what was to become the largest

debris-generating event on record.

In early 2007, an anti-satellite

missile test took place in LEO.

Its target? A dead weather satellite...

In less than 24 hours, the

debris encircled the earth,

hovering at the original impact

altitude of over 500 miles,

high enough so that the pieces

won't come down, but low enough

so that they have the potential to affect

almost all other objects in Low-Earth Orbit,

including the

International Space Station.

Today, as the debris cloud keeps

growing, so does our understanding of it.

The majority of debris

from this one event

will remain a hazard in our

skies for centuries to come.

This visualisation shows the

formation of one of the first galaxies,

massive stars filling

the universe with light,

beginning when it was

300 million years old,

and continuing up to its present

age of 13.7 billion years.

It's an awe-inspiring look at

the lifespan of the universe,

with galaxies forming,

and naturally colliding...

Ultimately spinning the massive

thread-like structure of the cosmic web...

At Lowell Observatory, Don Kessler is guided

by Kim Herman, post-doctoral associate.

Arizona's known for

its observatories, and

fortunately very close to

Meteor Crater is Lowell.

All my life I've been

interested in astronomy.

I've visited several

observatories that were designed

for the purpose of looking at

satellites, but never one with astronomy.

Here astronomers are

well-connected to the stars.

Bordered by a ponderosa

pine forest 8,000 feet up,

elevation and absolute

isolation create a pristine sky

for professional and amateur

astronomers of all ages.

The night sky here opens up infinite

possibilities for the naked eye.

Here the sky is so clear

and so dark that we don't

even need telescopes to see

what's going on in the sky.

Eyum is using her smartphone to

stargaze and know what she's looking at.

And over there Saturn

should be coming out.

When I think about Saturn's

beautiful rings, I think of collisions

in space and what earth could look

like millions of years from now.

Overtime, collisions would create more

debris and in turn even more collisions.

Gradually, the debris would shrink in

size and speeds would slow until finally

the Earth would be surrounded

by stable, Saturn-like rings.

When I look at the night sky the

first thing I notice is stars.

The beauty of the

universe is striking to me.

The next thing I'll notice is meteors.

If I see a meteor I feel

like I'm lucky, because that

also reminds me of these

particles passing through space.

Then I may notice something

flickering and moving

and realise that I'm looking at

a satellite orbiting the Earth.

Those satellites are there

because we put them there.

And I may see another one,

travelling in the opposite direction.

It could collide with the

first one; their paths do cross.

An astronaut was asked this question:

When you're in orbit and see these

things in space, does that worry you?

His answer was:
I worry

more about what I don't see.

Our belief that what goes up

must come down isn't always true.

It's estimated that LEO contains

6000 tonnes of space junk,

and GEO is home to 400 dead satellites,

parked into a higher graveyard orbit,

where they will remain

for hundreds of years.

That's a whole lot of junk.

So what exactly is out there?

Over the last 50 years, we've launched

several thousand objects into space.

Yet there are only around 1000 spacecraft

that are operational at this time.

What may surprise many people is that

once an object stops

functioning, we leave it in orbit.

Every single one of these non-operational

spacecraft is a potential source of debris.

In fact, most spacecraft that

are launched into the orbit

actually leave a trail

of debris in the process.

Upper-stage rocket bodies

weighing several tonnes

make up a good portion of junk in space.

...as do mission-related objects

like cast-off bolts, or o-rings...

The rest, of miscellaneous fragments,

exploded rockets, left-over fuel...

And the list goes on...

But even with this

incredible amount of debris,

few people were taking the

notion of space junk seriously

until the morning of February 10, 2009.

Earlier that day, a report

was issued predicting that

Iridium 33 would encounter a

close approach of just 1900 feet

with another spacecraft.

It's Cosmos 2251, travelling

at the same speed as Iridium.

Amazingly, this collision

alert wasn't even among the top

predicted for any of the Iridium

satellites for the coming week.

But at 4:
56 PM, the time predicted for

the close approach, Iridium 33 went silent.

Two satellites that had simultaneously

circled the planet for a dozen years

had collided.

Cosmos, as it turned

out, was a dead satellite,

ceasing to function in 1995, just

two years after it was launched.

Now more than a 100,000 pieces from

this collision cloud Low-Earth Orbit.

The Iridium-Cosmos collision

was very much a game changer.

There were those who thought of

space in terms of a Big Sky Theory,

that it was limitless and we didn't

need to worry about ever crowding it.

It became very obvious that that wasn't

true and people began to consider:

What do we need to do to keep

this from happening again?

Far from space, deep in the desert

near White Sands, New Mexico,

sits the remote

hyper-velocity test laboratory,

where engineers are providing

solutions required to advance

space travel in the face of

these gathering obstacles.

Scientists analyze what we can only

imagine:
hyper-velocity impacts,

collisions between objects travelling

at speeds of up to 15,000 miles per hour.

These scientific visualisations show

a fragment no bigger than a beebee...

...blasting through an aluminium plate,

typically used to protect spacecraft.

Even the smallest of impacts scatter

debris, delivering wide-spread damage.

Whether it's a circuit board or a wayward

bolt, or even the tiniest chip of paint,

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