Our future is in ruins: the archaeology of space, satellites and orbital junk
By James Purtill
Next year will mark six decades of space travel. Orbiting above us are more than one hundred million pieces of debris from this age of exploration — everything from specks of paint and flecks of plastic, to the tool bag dropped by a US astronaut in 2008, to the bus-sized European observation satellite that unexpectedly fell silent four years ago.
Here’s how the number of man-made objects in orbit has gone up since 1957, the year Russia launched the very first satellite, Sputnik 1.
Twelve years ago, Australian archaeologist Dr Alice Gorman began thinking about the historical value of what is commonly called ‘space junk’. Space junk makes space more hazardous. Satellites have to dodge the criss-crossing, intersecting paths of swarms of debris that are whizzing about faster than a bullet, and on paths that are constantly changing as they ricochet into each other. When debris collide, they shatter into smaller parts, and this process has the potential to snowball, with the debris from collisions dispersing and causing more collisions, until eventually there are no working satellites.
This chain reaction, known as the Kessler Syndrome, could destroy more than $1 trillion worth of satellites in only a few weeks. The Earth would be enveloped in a self-generating screen of orbiting projectiles. The remains of our first, optimistic forays into space would then haunt us, making it much harder for us to leave our planet.
According to experts employed by the US Government, there is enough debris in space for this domino effect to occur today. We have passed the tipping point. We actually passed that point about 14 years ago, when there was fewer debris.
The problem of cleaning up the junk isn’t simply technical, it’s legal and diplomatic, according to Dr Gorman, a senior lecturer at Flinders University, and a member of the advisory council of a national not-for-profit promoting the space industry in Australia. She said a story about a new ways of cleaning up space junk is a “non-story”.
“All those legal and international relations issues are not resolved. It doesn’t matter how good the technology is,” she said.
One of those stories came out this week: a new kind of satellite with a tether to knock space junk out of orbit. Japan will deploy the prototype early next year. Other proposed solutions are like a combination of the Steve Zissou and Star Wars: satellites with nets to capture debris (European Space Agency), satellites that can harpoon other satellites (also the ESA), satellites that can grab and drag other satellites, and ground-based photon cannons to nudge satellites out of orbit and into a death spiral (Australian researchers).
“The difference between zapping a thing that is junk and zapping a thing that is a military surveillance satellite and saying ‘whoops’, isn’t very big,” Dr Gorman said.
“The problem isn’t the technology, the problem is the anti-satellite weaponry.”
“No one wants a major international incident because of that, and there there’s no international agreement that makes people feel safe enough for that to happen.”
There is an international agreement that covers space, but it was drafted when the space age was only 10 years old. The 1967 Outer Space Treaty does not distinguish between satellites and space debris; the Japanese prototype to be launched next year will take out ‘space junk’ that has the same legal status as a working satellite. Most legal experts agree the debris of a satellite remain the responsibility of the nation that launched the object, but in practice most space junk is stateless. It’s impossible to figure out where it came from and no incentive to try. It’s an awkward situation.
At the same time, satellites are becoming cheaper and smaller. You can build and launch a pumpkin-sized satellite for the price of a sedan. This trend will make it harder to distinguish between satellite and junk based on size.
Japan better be careful with that tether.
Which satellites need to be saved
These are the hurdles to cleaning up space junk, but it’s clear that, at some point, perhaps after a Gravity-like disaster, we will begin cleaning our orbit space. When that happens, Dr Gorman wants to keep a few historical satellites from the wreckers.
She gave us her personal top five.
1. Vanguard 1
This was the fourth satellite ever launched and is now the oldest human object in orbit (the three others have all fallen back to earth). It was launched by the US in 1958. The polished aluminium sphere was the first satellite to use solar panels.
“I love that early silver sphere design which isn’t used anymore. It wasn’t used very much after the 60s. It has quite a retro feel. It really feels like a Space Age object.”
“I think it’s a beautiful object in its own right.”
2. Asterix-1
This was the first French satellite, launched in 1965. It’s painted with stripes as a form of temperature control — the black absorbs heat, the white reflects. Like the silver sphere of Vanguard, Asterix’s design embodies the Space Age aestehtic.
“It’s a cute stripey object that makes you think of Asterix and Obelix,” Dr Gorman said.
3. Australis-OSCAR 5
This was built and designed by a bunch of physics and law students from Melbourne University. They teamed up with a US-based amateur radio group who convinced the US Air Force Space Command to let the satellite piggyback on a military rocket. It was built in the ’60s and finally launched in 1970. It was the first remote-control amateur satellite.
“I love it because it proves anyone can get involved in space,” Dr Gorman said.
4. TRAAC — Transit Research and Altitude Control
A year after TRAAC was launched in 1961, the US tested a nuclear bomb at high-altitude — Starfish Prime was the largest man-made nuclear explosion in space. The blast created an unexpectedly large electromagnetic pulse (EMP) that knocked out a bunch of satellites (and blew out streetlights in Hawaii, 1500km away). TRAAC was one of the casualties.
It was also engraved with the first poem to be launched into orbit: And now ’tis man who dares assault the sky / And as we come to claim our promised place, aim only to repay the good you gave, And warm with human love the chill of space.
“The little satellite actually played a role in Cold War nuclear politics,” Dr Gorman said.
“People were so horrified by [the high-altitude nuclear test] that it led to the implementation of the Limited Nuclear Test Ban Treaty.”
5. Syncom 3
This was the first geostationary satellite, meaning it orbits the Earth at the same rate as the planet turns — it basically stays in the same spot in the sky. Launching it into this orbit was a huge technical achievement. The first satellite ever, Sputnik, had an orbiting altitude of 577km above the Earth. Seven years later, Syncom 3 reached 35,000km.
The first two attempts to reach this altitude failed. The geostationary orbit is now the most lucrative space real estate going.
You can get an idea of the different kinds of orbits with this handy interactive map.
“Syncom 3 was used for military stuff, and it was also used to broadcast the 1964 Summer Olympics in Tokyo to the US,” Dr Gorman said.
“It meant people needed to get TVs to watch the Olympics, so it gave a huge impetus to the Japanese electronics industry. It was also a huge boost for the Olympics movement, because so many people in the US could watch it now.”
Dr Gorman isn’t calling for these satellites to be lassoed, hauled back to earth, and set up in some terrestrial museum. This would be hugely expensive and not very safe.
She says it’s better to leave the satellites where they are, watching over us.
Originally published at www.abc.net.au on December 14, 2016.
