page_title: Ion source
section_title: Gas-discharge ion sources
hierarchical_section_title: Ion source / Gas-discharge ion sources
caption_attribution_description: English: Image of NASA's Evolutionary Xenon Thruster (NEXT) - 7 kilowatt ion thruster, tested for more than 48,000 hours of operation in vacuum chamber.
context_page_description: An ion source is a device that creates atomic and molecular ions. Ion sources are used to form ions for mass spectrometers, optical emission spectrometers, particle accelerators, ion implanters and ion engines.
context_section_description: These ion sources use a plasma source or electric discharge to create ions.
caption: NASA's NEXT (ion thruster) space craft propulsion system
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