Vid Good news: the latest resupply mission to the International Space Station has taken off without exploding or any of that kind of nonsense.

Even better news: it is carrying 5.9 metric tons (6.5 US tons) of cargo, including a rather unusual device that boffins believe could be a great tool for dealing with space junk.

After the failure of a Russian resupply mission earlier this month, the cargo for this flight has been reordered slightly but includes 600 litres (106 gallons) of water (enough for four month's use – including yesterday's coffee) and six lithium-ion battery orbital replacement units (ORUs) to replace the aging nickel-hydrogen batteries on the ISS.

And built into the side of the cargo capsule is the Kounotori Integrated Tether Experiment (KITE), which consists of a 20-kilogram (44-pound) weight attached to a 700-metre (765-yard) tether of metallic mesh line. The line was specially created for the job by the venerable Japanese fishing net manufacturer Nitto Seimo Co.

KITE has been built to demonstrate electrodynamic tethering, whereby unshielded metallic lines extended in space pick up an electrical charge as they move through Earth's magnetic field. The principle has been used before to generate power, but now scientists want to try attaching a tether to larger pieces of space junk to de-orbit them.

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Once the cargo pod has been emptied and refilled with rubbish, it'll detach from the space station and move away under remote control. The KITE line will then extend and for seven days the unit will monitor the electricity generated and see if it would be enough to either power a defunct satellite out of orbit, or act as a drag to pull it down slowly.

If the tests look good, the scientists want to build small robot probes that can attach themselves to end-of-life orbiting hardware and then extend a tether 5,000 or 10,000 metres (5,468 or 10,936 yards), which should be enough to do the job.

Once the experiment has been completed and the data transferred, the cargo ship will be doing some descending of its own. It is expected to burn up in the atmosphere and any remaining parts will crash into the Pacific.

And speaking of burning – SpaceX's last explosion has now officially cost them a customer. Global communications firm Inmarsat has said it is dropping SpaceX for the launch of its S-band satellite for the European Aviation Network (EAN) because of delays in being given clearance for launches.

"We are delighted with the flexibility that Arianespace has shown in being able to provide a launch slot that enables us to place our European Aviation Network S-band satellite in orbit by mid-2017," said Michele Franci, CTO of Inmarsat. ®