You are watching a sample version.

00:30 Horizon

The Trouble with Space Junk

Worldwide captioned version

FKA C 957F/50

PORTLAND POST

Portland Post Production

80 Great Portland Street

London W1W 7NW

020 7436 8262

www.portlandpost.tv

01:00 [music]

01:05 BBC

Al Down, I see her. Right cable is down and I see you to go for configuration, Steve.

01:10 Steve Thank you, Al.

01:15 Helen McCrory 220 miles above the Earth on the 12th of March 2009, was a day like any other on the International Space Station.

01:25 Steve Two, three (inaudible).

01:30 [music]

01:35 Sandra Magnus It was mid-morning and I was getting ready to exercise. And we were just sort of getting into our mid-morning routine, if you will.

01:40 UNKNOWN Okay, Nick. On my way.

01:45 Helen McCrory But then they got an unusual message.

01:50 Sandra Magnus We got a call that we were having "a red conjunction". We were looking around, "What the heck is a red conjunction?" You know, because we hadn’t really trained for it.

02:00 Helen McCrory A red conjunction is a warning code that the space station could be hit by some orbital debris.

02:10 Sandra Magnus It was a little bit chaotic, because this was the first time we had one of these.

02:15 Helen McCrory The space station was traveling at nearly 8km per second. The space junk was traveling at the same speed in the opposite direction. If they hit, the consequences could be catastrophic.

02:35 Hugh Lewis It gets hit by something relatively small. Penetrates, but because of the pressure inside, it just forces the modules to open up just like a balloon bursting. And that happens extremely quickly, with no chance that an astronaut in that module could… could… could ever get out.

02:55 UNKNOWN Copy, Al. You’re on your way to the station.

03:00 Helen McCrory NASA was taking no chances and scrambled astronaut Sandra Magnus to the Soyuz life raft. All she could do then was sit and wait.

03:15 Sandra Magnus And it’s either going to hit or it’s not going to hit. And so worrying about it doesn’t help you.

03:25 Helen McCrory Was this just an isolated incident or was it a sign of a growing threat to life in space and modern life on Earth?

03:40 [music]

03:45 horizon

THE TROUBLE WITH SPACE JUNK

03:50 5

4

3

03:55 2

1

UNKNOWN Five, four, three, two, one and liftoff.

04:00 UNKNOWN First stage move. Propulsion performing normally.

04:05 [music]

04:15 Helen McCrory Space, endless and empty. At least that’s what we used to think. In the last few decades, orbits around Earth have become crowded with satellites and littered with space junk.

04:35 Dr Hugh Lewis

University of Southhampton

Hugh Lewis So space junk is all the stuff that we’ve launched into… into orbit that no longer serves a useful purpose. So, it’s satellites, it’s rocket bodies, it’s, you know, old gloves. It’s toolkits that astronauts have accidentally dropped. Basically, litter that we’ve… there is left… left in space.

05:00 [sil.]

05:05 Helen McCrory But littering space is much more dangerous than it is on Earth.

05:10 General John E Hyten

Air Force Space Command

John E Hyten Those objects are going at 17,000 miles an hour. And when you’re going 17,000 miles an hour, it does not take a big piece of debris to ruin your day.

05:20 [music]

05:30 Helen McCrory Satellites are virtually defenseless against high-speed orbital debris. And they are crucial to modern life on Earth.

05:45 Dr Roger Thompson

Centre for Orbital and Re-Entry Debris

Roger Thompson We are far more connected and far more dependent upon satellites than most people really know. The ability to make phone calls, the way we do it now was just a dream less than 100 years ago. We’re all connected to the internet. Weather satellites, navigation systems, it’s almost impossible to get lost, despite what the guidance says on the GPS about turn left and turn right.

06:15 Helen McCrory All of that and more is becoming increasingly vulnerable.

06:20 Hugh Lewis Unless we tackle the… the debris problem, there is going to be no weather forecast, there is going to be no news story from… from the other side of the world. You’re not going to be able to turn on the television and see the World Cup.

06:35 [sil.]

06:40 Helen McCrory But how did space become littered with dangerous debris?

06:45 UNKNOWN Today, a new moon is in the sky. A 23-inch metal spear placed in orbit by a Russian rocket.

06:55 Helen McCrory Space was a pristine environment, until the launch of Sputnik in 1957. But in the first decades of spaceflight, every time a rocket or satellite was launched, it left behind some debris.

07:15 [sil.]

07:30 United States

Discovery

Helen McCrory No-one thought it was much of a problem until this man, Donald Kessler, did some calculations. He was working for NASA in the late 60s and early 70s, when he discovered that leaving junk in orbit wasn’t like dumping junk on Earth.

07:50 Don Kessler

Former NASA senior scientist

Don Kessler People tend to think of orbit like a road through space. I mean, as long as you stay on your road, you’re not going to get hit. It would be more accurate to think of the Earth as being one big paved planet. And when you want to go someplace, you drive in a straight line from one place to another and, of course, with no stop lights and… and no place to stop and you’re going to be running into each other in all kinds of directions. That’s exactly what you’ve got in orbit. So I headed up with an equation where I could write the spatial density, its apogee and inclination. Then you can do neat things like…

08:25 Helen McCrory His calculations predicted that, if bits of junk started smashing into each other at such huge speeds…

08:35 Don Kessler Unit volume, if you want to know the flux, the spatial density…

Helen McCrory …they’d create a cascade of collisions that would litter orbits with dangerous debris.

08:45 Don Kessler The integral of S squared…

Helen McCrory This became known as the Kessler Syndrome.

08:50 Don Kessler …integrated over the volume. In other words, if you never launch anything else in space, there will still be this cascading phenomena that continues to grow and, actually, it continues until you essentially grind up all the satellites into small dust particles.

09:10 [music]

09:15 UNKNOWN Three passed SV and 26.

UNKNOWN No time critical commanding. No satellite conjunctions. Good on step six.

09:20 UNKNOWN All data feeds to externals are open and both communication lines to the site are good.

09:25 UNKNOWN No applicable sieves or TPs. You’re good to execute.

09:30 UNKNOWN Copy that, ma’am.

Helen McCrory The prospect of this nightmare scenario was so worrying that in the early 80s, the American Air Force started cataloguing space junk. The technology only allowed them to track objects slightly bigger than a cricket ball.

09:50 UNKNOWN Give level one a call on the TTC-56.

09:55 Helen MCCrory They started at 6,000 pieces. And that number grew slowly to 10,000 over the next two decades, helped by an international agreement calling for used rocket bodies to be returned to Earth and burned up in the upper atmosphere.