A Mini-Crown for a Micro Rocket (image) Michigan Technological University Share Print E-Mail Caption This is L. Brad King's prototype of a ferrofluid ion thruster. When subjected to voltage, the points of the crown rise from a ring-shaped trench circling a one-inch block of aluminum. Ions shooting from the points create enough thrust to power a micro rocket. Credit L. Brad King Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.