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Another option is managed re-entry.

Managed re-entry is often used for large craft on short missions, but it can be very difficult to arrange for long-term missions.

As well as brightening the sky and interfering with astronomy through their flashes and radio waves, satellites pollute the atmosphere on launch and on re-entry, as research from last October underscored.

But it's not just such remote sites that are impacted by satellites, which exert effects on the local and global environment both at launch and at re-entry.

"We're starting to see that we might be reversing some of the gains we've made from the Montreal Protocol through these increased rocket launch and re-entry rates," Barker said.