After digging a bit: https://en.wikipedia.org/wiki/Project_West_Ford https://en.wikipedia.org/wiki/Project_West_Ford > The needles were placed in medium Earth

After digging a bit: https://en.wikipedia.org/wiki/Project_West_Ford https://en.wikipedia.org/wiki/Project_West_Ford > The needles were placed in medium Earth orbit at an altitude of between 3,500 and 3,800 kilometres (2,200–2,400 mi) at inclinations of 96 and 87 degrees. This is problematic as they are MEO not LEO. From https://www.spaceacademy.net.au/watch/debris/orblife.htm https://www.spaceacademy.net.au/watch/debris/orblife.htm - this is off their chart (which goes to 900km and 1000 years). Likewise, https://www.lizard-tail.com/isana/lab/orbital_decay/ https://www.lizard-tail.com/isana/lab/orbital_decay/ only goes up to 500km. https://www.n2yo.com/satellites/?c=37 https://www.n2yo.com/satellites/?c=37 for a tracker.