THE KESSLER SYNDROME: For billions of years, the heavens surrounding Earth were clear, untouched by mankind. Then in 1957, Sputnik One was launched by Russia. It was Earth's first man-made satellite. For the next 55 years, over 4,500 space missions have launched and left behind millions of pieces of debris. Life on Earth grows more dependent on space each day whether we notice it or not.
Space exploration has given us the technological advances that make our lives easier, teach us more about our world and protect us from danger. And soon, with the advent of commercial space travel, space will become accessible to anyone. But what if you woke up tomorrow and your GPS couldn't give you directions? What if your television showed nothing but static?
What if there were no warnings for the next natural disaster? The growing halo of man-made debris encircling the earth not only threatens future space exploration and global communications, but potentially endangers us all. If mankind doesn't act soon, the natural resources of space will become dangerous, unusable, and we'll be helpless to stop it.
Collision Point: The Race to Clean up Space: It all began with a misconception. We once believed that space was so vast, that it would be unlikely that two objects could collide with one another in orbit. Leaving something behind in space seemed harmless. But then in 1978, one man realized the real danger, that the big sky wasn't so big after all. That man was Don Kessler, NASA's retired senior scientist for Orbital Debris Research.
Pre-1978, there was this "Big Sky Theory," that there's so much space and the only thing we need to worry about was meteroids. What about satellites in Earth orbit? When are they going to start colliding and when will that become a significant hazard? The hazard from the meteor environment had already been exceeded by the man-made environment. You can draw an analogy to climate change in the sense that it's a long-term problem. It will slowly continue to get worse.
Space debris is any object in orbit around Earth that serves no useful function and it can consists of rocket bodies that were used to place the object in orbit or it can be payloads that have quit functioning. Rather than putting things out of the way, we're just turning them off. To understand the problem of orbital debris, one must first understand orbits. Orbit is nothing more than the path an object takes when it falls through space. There are several orbit regions around the Earth.
Among them are the low Earth orbit, or LEO, medium Earth orbit, or MEO, and the geosynchronous orbit, or GEO. But how much debris has been left behind in these orbits? There have been over 4,500 satellites launched into space and about 1,000 of them are active. The Air Force can track objects that are about 5 to 10 centimeters or larger, and they are tracking, right now, over 20,000 objects that they know of, mostly all space junk. And just how dangerous is this junk?
Dead satellites and spent rocket stages left in low Earth orbit travel at 17,000 miles per hour. That's ten times faster than a rifle bullet. So if you were living in space, it's like living on a shooting range. In space, colliding with an object the size of a marble would have the energy equivalent to a hand grenade. As the size increases, so does the danger.
These lethal objects ranging from one centimeter to just under ten centimeters cannot be tracked reliably using ground-based radar. There are estimated to be more than 500,000 objects of this size in orbit. It is humbling how space reveals the fragility of man-made objects. But what happens if these collisions start to add up? The fear is that even just one incident could lead to a chain reaction known as . . . . .
The Kessler Syndrome. . . . .
Black. Silence. At 600 kilometers above planet Earth, the temperature fluctuates between plus 258 and minus 148 degrees fahrenheit. There is nothing to carry sound, no oxygen, and no air pressure. Life in space is impossible. Like all images of Earth seen from space, this image of our planet is mythical and majestic. The globe seems almost tangible, slowly spinning, floating in the endless void of space.
It is a blue planet, and bright white clouds twirl and stretch in capricious patterns across the deep blue of the oceans and the jigsaw of continents: green, yellow and brown. It is noon in Cape Town and early night in India. The sphere is almost a perfect orb except for the darkened sliver on its Eastern edge. It is beautiful! And so full of life. But not here. Here it is completely silent.
Orbiting at an altitude of 600 kilometers, the Explorer Space Shuttle becomes visible. This icon of space exploration has played a key role in all of NASA�s missions since the late 90�s. Faintly we hear static, voices murmuring over radio frequences.
As the babble builds we might hear one conversation amongst the rest. Matt Kowalski, a veteran astronaut commanding his final expedition, floats thirty meters away from the Shuttle wearing a bulky white space suit and a full, bubble-like helmet. Matt fiddles with a control and propels himself away from the Shuttle.
Stationed around the telescope are two astronauts carrying out a repair mission. They are also wearing space suits but unlike Matt, they are not wearing Manned Maneuvering Units. Safety tethers are the only things stopping them from floating away into space. Matt is telling Mission Control/Houston his wild stories on Earth, which they've heard them before.
Shariff Dasari is an Indian engineer in his mid-thirties. He is attached with tethers to a platform on one side of the Hubble. This is his second mission into outer space. Mission Control congratulates him for his successful repair of the Hubble Telescope. Shariff cheers and begins singing a pop tune in Hindi, bursting into a Zero-G Bollywood choreography that is repressed by the stiffness of his space suit.
Matt is now approaching the Explorer, skillfully maneuvering his thrusters. The other astronaut stands perched on a robotic arm attached to the Shuttle. The arm is a crane-like moving platform remotely operated from inside the Shuttle. We track in on the astronaut as she works intently alone.
Dr. Ryan Stone is a medical engineer, specialized in hospital scanning systems. She�s focused on her work as though she�s all alone in the world. This is her first mission. She's working on a rack of circuit cards, but Mission Control reports it's still not functioning.
Ryan eyes the card and moves it around. She starts to disengage one of the panels. Ryan takes out a card from under the plate and begins to examine it. Matt begins to approach her. Without losing any time, Ryan puts the card back into the telescope. Ryan hums as she jiggles the card.
Matt begins a wide loop around the telescope. She reports it will take her one hour to make the necessary corrections. Ryan continues to work. Matt closes in as he circles the telescope.
Mission Control informs Matt that the delay will not be long enough for him to surpass the spacewalking record held by Anatoly Solovyev. Ryan begins unbolting. Matt lands right next to Ryan,grabs onto the telescope, and tethers himself to a rail. Ryan is frustrated, determined.
Ryan is not as precise with her pistol grip, and when a bolt comes off, she drops it. The bolt spins floating away. She tries to grab it but misses, barely touching it but brushing it just enough to give it a push that makes it change direction.
She turns and reaches out to grab it, but she is strapped to the Robotic Arm. The bolt spins out into the emptiness of space. Matt reaches out and grabs it before it has gone too far. Ryan looks at him, embarrassed. Matt hands it back to her, she puts the bolt away. Matt takes out his pistol grip, and with fast precision puts its head to a bolt and begins unscrewing. Matt removes the bolt with confidence.
Mission Control radios a NORAD report that a Russian satellite has incurred a missile strike. The impact has created a cloud of debris orbiting at 20,000 miles per hour. Current debris orbit does not overlap with their trajectory and they will keep them posted on any developments.
Ryan glances at Matt, asking whether they should be worried. He tries to put her at ease. Ryan instructs Explorer to engage arm and pivot to cargo bay. The robotic arm moves very slowly, pulling Ryan along while Matt begins to unharness from the telescope to shift his position.
Matt asks her questions - how she likes working for NASA, how long was her training, and what is this scanning system. It�s a new set of eyes to scan the universe that was actually for hospital use. Shariff calls for Matt's attention. Matt turns.
Shariff raises his arms again, jumps and floats away from the Shuttle, screaming and flapping his arms. A long safety tether attached to his waist tenses and brings Shariff to an abrupt stop, snapping him back like a bungee cord. Matt states for Ryan's benefit, "And to think he went to Harvard."
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