A Japanese cargo vessel carrying an experimental tether to de-orbit space debris is on its way to the International Space Station.
The device is part of the payload on board the H-II Transfer Vehicle Kounotori 6, which launched from the Tanegashima Space Centre on December 9. Known as an electrodynamic tether, or EDT, the junk catcher is made from thin wires of stainless steel and aluminium. It attaches to large pieces of debris, then uses the force created by passing through the Earth’s magnetic field to drag the junk into lower orbits, eventually burning up in the planet’s atmosphere.
After ten years in the planning, the project will culminate when the tether is deployed from the Kounotori as it leaves the ISS with a payload of waste material. The EDT is the result of a collaboration between the Japan Aerospace Exploration Agency (JAXA) and Japanese fishing net manufacturer Nitto Seimo.
“The tether uses our fishnet plaiting technology, but it was really tough to intertwine the very thin materials,” Nitto Seimo engineer Katsuya Suzuki told AFP.
“The length of the tether this time is 700 metres (2,300 feet), but eventually it’s going to need to be 5,000 to 10,000 metre-long to slow down the targeted space junk.”
Orbiting debris is a problem that has worried space agencies around the world for many years. Around 500,000 pieces of space junk are currently being tracked, with around 20,000 of these being larger than an apple. On top of this, NASA estimates there are many millions of pieces of debris that are so small they can’t be tracked.
Several solutions for removing space debris from orbit have been suggested, including solar sails, ion cannons, harpoons and mechanical arms.
Interesting concept I wonder if could be applied to most launches going forward? Then it would need to be calculated where each launch is going – what space junk is along the way and how much of the tether net is needed – remembering that every once and cubic centimeter of space is important and each participating launch gets a little extra payload that is released enroute and then sweeps an area of space junk clean? Assuming that keeping things tidy has value …
How does debris get into orbital space in the first place?
Does it shake loose from vehicles entering or leaving orbit? Do bits just fall off from impacts with other debris or micro-meteors? Is it loose ends from extravehicular activities? If the last of these plays a significant part, could nets like this adapted fishing net be deployed in the work area around mission specialists during their EVAs? Is periodic near-earth-orbit cleanup something that could be automated and monitored (a la garbage-duty space drones)?
How will burning space junk heat the atmosphere and contribute to global warming?
A new space elevator concept will help to make us a true space faring civilization .
It has multiple tethers at its center ( for greatest strength ) and
fewer tethers as you move away from center ( for lesser amounts of mass ) . It is also in an elliptical geosynchronous orbit , so it appears to drop straight down from space , pick up a payload , and return to space , thus requiring a much smaller system than an earth based space elevator. We already have material strong enough to get us within the distance of the lunar gravity center ( around 6,000 mi. ) add the proposed system above and we could do this now!
Let’s get started.
What do you think?
The space elevator is a nice idea but the space fountain is better.
An interesting propellantless idea- but a bit of further reading suggests that the time to deorbit an medium-sized satellite (1500kg) in LEO ranges from 15 days in a 400km orbit to almost a year at 1400km- isn’t dangling a 10,000m cable from every piece of debris targeted for that length of time going to create an enormous amount of extra material in orbit for a still-functioning asset to collide with?