LinkNotes: microwave

2008-09-25

China Will Build The EmDrive A New Concept in Spacecraft Propulsion

China recently reported to have build the highly controversial Emdrive (electromagnetic drive), an engine that uses microwaves to transform electrical energy into thrust. A technology that might be a breakthrough in spacecraft propulsion technology.

The EmDrive

Clipped from: Emdrive - Home

Satellite Propulsion Research Ltd (SPR Ltd) a small UK based company, has demonstrated a remarkable new space propulsion technology. The company has sucessfully tested both an experimental thruster and a demonstrator engine which use patented microwave technology to convert electrical energy directly into thrust. No propellant is used in the conversion process. Thrust is produced by the amplification of the radiation pressure of an electromagnetic wave propagated through a resonant waveguide assembly.

Details (Slideshow)

Clipped from: EMDrive presentation at Space 08 conference, Barbican, London

EMDrive presentation at Space 08 conference, Barbican, London
View SlideShare presentation or Upload your own. (tags: spr shawyer)

Criticism

Clipped from: EmDrive - Wikipedia, the free encyclopedia

EmDrive (also Relativity Drive) is the name of a spacecraft propulsion system proposed, and reportedly developed, by Roger Shawyer.^[1] New Scientist ran a cover story on EmDrive in its September 8, 2006 issue.^[1] The device is a Magnetron with a specially shaped fully enclosed tapering resonator cavity whose area is greater at one end. The inventor claims that the device generates thrust even though no detectable energy leaves the device. The inventor proposes to use it as a spacecraft propulsion system that uses no fuel (other than electricity).

On his homepage[1] the inventor claims that independent peer-review is under way, but so far no publication is available.

The device's operation as described seemingly violates several basic laws of physics, notably conservation of momentum, though the inventor insists to the contrary. John Costella, an expert in relativistic electrodynamics describes the EmDrive as a 'fraud'.^[2]

Project in China

Clipped from: Chinese Say They're Building 'Impossible' Space Drive | Danger Room from Wired.com

Chinese Say They're Building 'Impossible' Space Drive
Chinese researchers claim they've confirmed the theory behind an "impossible" space drive, and are proceeding to build a demonstration version. If they're right, this might transform the economics of satellites, open up new possibilities for space exploration –- and give the Chinese a decisive military advantage in space.

[...]
What will China do with the technology? It may be relevant that professor Yang is not unknown in military circles, having published a paper called "Plasma Attack Against Low-Orbit Spy Satellites."

Meanwhile, what about the American interest? Shawyer told me that "the flight thruster program is on hold for the present. [O]nce the U.K. government had provided an export license for a U.S. military application, the major U.S. aerospace company we had been dealing with stopped talking to us. "

The company may have decided that the Emdrive could not work. If they're wrong, China has at least a year's head start in a technology that will dominate space and make previous satellites as obsolete as sailing ships in the age of steam.

2008-03-07

NASA’s WMAP (Wilkinson Microwave Anisotropy Probe)

New results, just released from NASA's WMAP (Wilkinson Microwave Anisotropy Probe), detecting microwaves coming from the cooling fireball of the Big Bang.

clipped from wmap.gsfc.nasa.gov

WMAP Highlights

Wilkinson Microwave Anisotropy Probe

The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA Explorer mission. It has produced a wealth of precise and accurate cosmological information. WMAP produced the first full-sky map of the microwave sky with a resolution of under a degree, about the angular size of the moon.