Europe's Lunar Adventure Begins

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                        HOW SMART 1'S ION DRIVE ENGINE WORKS
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    <b>1. </b>Xenon gas atoms are pumped into a cylindrical chamber, where they collide with electrons from the cathode. The electrons - which are negatively charged - knock electrons off the Xenon atoms, creating Xenon ions - which are positively charged.<br /><br /><b>2.</b> Coils outside the chamber create a magnetic field, which causes electrons from the cathode to spiral and become trapped at the mouth of the chamber.<br /><br /><b>3.</b>  The build-up of negatively-charged electrons at the mouth of the chamber attracts the positively-charged ions, accelerating them out of the chamber.<br /><br /><b>4.</b> The stream of accelerated ions leaving the chamber thrusts the spacecraft forward. Although the force is small, over time it creates great speed in the frictionless environment of space.

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