Editing Interstellar travel (section)

==== RF resonant cavity thruster ====
A radio frequency (RF) resonant cavity thruster is a device that is claimed to be a [[Spacecraft propulsion|spacecraft thruster]]. In 2016, the [[Advanced Propulsion Physics Laboratory]] at [[NASA]] reported observing a small apparent thrust from one such test, a result not since replicated.<ref>{{Cite web|url=https://www.nationalgeographic.com/news/2016/11/nasa-impossible-emdrive-physics-peer-review-space-science/|title=NASA Team Claims 'Impossible' Space Engine Works—Get the Facts|date=2016-11-21|website=National Geographic News|language=en|access-date=2019-11-12|archive-date=12 November 2019|archive-url=https://web.archive.org/web/20191112135532/https://www.nationalgeographic.com/news/2016/11/nasa-impossible-emdrive-physics-peer-review-space-science/|url-status=dead}}</ref> One of the designs is called EMDrive. In December 2002, Satellite Propulsion Research Ltd described a working prototype with an alleged total thrust of about 0.02 newtons powered by an 850 W [[cavity magnetron]]. The device could operate for only a few dozen seconds before the magnetron failed, due to overheating.<ref>{{Cite web|url=http://rexresearch.com/shawyer/shawyer.htm|title=Roger SHAWYER -- EM Space Drive -- Articles & Patent|website=rexresearch.com|access-date=2019-11-12|archive-date=14 September 2019|archive-url=https://web.archive.org/web/20190914002837/http://www.rexresearch.com/shawyer/shawyer.htm|url-status=live}}</ref> The latest test on the EMDrive concluded that it does not work.<ref>{{Cite web|url=https://www.sciencealert.com/impossible-em-drive-test-concludes-external-thrust|title=The Latest Test on The 'Impossible' EM Drive Concludes It Doesn't Work|last=McRae|first=Mike|website=ScienceAlert|date=24 May 2018|language=en-gb|access-date=2019-11-12|archive-date=12 November 2019|archive-url=https://web.archive.org/web/20191112135539/https://www.sciencealert.com/impossible-em-drive-test-concludes-external-thrust|url-status=live}}</ref>