Editing Beam-powered propulsion (section)

=== Microwave thermal rocket ===
{{Main|Thermal rocket}}
In 2002, [[Kevin L. Parkin|Kevin L.G. Parkin]] proposed a similar system using microwaves.<ref name="parkin" /><ref>Parkin, K. L. G., et al. (2002). A Microwave-Thermal Thruster for Ultra Low-Cost Launch of Microsatellites, Jet Propulsion Center, California Institute of Technology.</ref><ref>{{cite news| url=http://www.foxnews.com/scitech/2011/01/25/nasa-exploring-lasers-beams-zap-rockets-outer-space/ | work=Fox News |first=Prachi |last=Patel | title=NASA Exploring Laser Beams to Zap Rockets Into Outer Space | date=25 January 2011 |url-status=dead |archiveurl=https://web.archive.org/web/20110127183155/http://www.foxnews.com/scitech/2011/01/25/nasa-exploring-lasers-beams-zap-rockets-outer-space/ |archivedate=2011-01-27}}</ref><ref>{{cite magazine|url = http://www.scientificamerican.com/article/microwave-powered-rockets-would-slash-cost-of-reaching-orbit/|title = Microwave-Powered Rockets Would Slash Cost of Reaching Orbit|date = December 1, 2015|magazine = Scientific American |doi=10.1038/scientificamerican1215-33}}</ref> In May 2012, the DARPA/NASA Millimeter-wave Thermal Launch System (MTLS) Project<ref>{{Cite book|title=Microwave Thermal Propulsion - Final Report|last=Parkin|first=Kevin|publisher=NASA|year=2017|hdl = 2060/20170009162}}</ref> began the first steps toward implementing this idea. The MTLS Project was the first to demonstrate a millimeter-wave absorbent refractory heat exchanger, subsequently integrating it into the propulsion system of a small rocket to produce the first millimeter-wave thermal rocket. Simultaneously, it developed the first high-power cooperative target millimeter-wave beam director and used it to attempt the first millimeter-wave thermal rocket launch. Several launches were attempted, but problems with the beam director could not be resolved before funding ran out in March 2014.