The hunk of space junk is only about 10 centimetres in diameter, or somewhere around the size of a cricket ball. Sounds tame, but debris moves seriously fast in orbit -- trash can zip by at speeds of 17,500 mph, around 30 times faster than a bullet fired from a gun.
At that speed, even a small piece of rubbish could cause a puncture in the ISS.
As such, the station will fire its Zvezda service module engines at 4pm UTC on 13 January, and move itself outside of the debris' trajectory. Without the manoeuvre the object would have made two close approaches to the station on consecutive orbits, passing with an overall miss distance of between one and 24 kilometres.
The avoidance manoeuvre also means that the ISS won't have to reboost next week for the planned docking of the ISS Progress 46 cargo ship, later in January.
The space agency tracks debris with such precision -- more than half a million pieces of junk are simultaneously watched by Nasa -- that it knows exactly where the object came from. It's a piece of an Iridium satellite, from a huge cluster of orbiting satellites that provide voice and data coverage to Earth.
This isn't the first time that the Iridium array has made a nuisance of itself. On 10 February, 2009, Iridium 33 collided with the defunct Russian satellite Kosmos 2251 at roughly 22,000 mph. It was the first time that two intact satellites collided, and the impact wrecked Iridium 33.
The last time the ISS moved was in September 2011. Back in June astronauts had to briefly take shelter in the Soyuz escape capsule as debris flew perilously close by the space lab.
Nasa says there are more than 20,000 pieces of debris larger than a tennis ball orbiting the Earth, 500,000 pieces of debris the size of a marble or larger and many millions of pieces of junk that are so small they can't be effectively tracked.
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