Earth's low orbit is filled with satellites — some new, some decades old. This has become an issue as orbit fills with space debris from broken or failed satellites, making removing them a challenge.

Scientists at the European Space Agency have created a miniaturized ion thruster that’s capable of keeping a satellite steady while in Earth’s orbit. Liquid metal forming on a tiny spiked crown made ...

Predicting the lifetime of an electric ion thruster is notoriously difficult. You have to account for the chamber wall ...