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Despite 50 years of research on high-power microwaves, the us military has yet to produce a usable weapon.

A team of researchers at Colorado based Escape Dynamics is reporting that initial tests indicate that it might really be possible to launch space-planes into space using microwaves sent from the ground, to allow for a single stage spacecraft. If the idea pans out, the cost savings for sending satellites (or perhaps humans) into orbit could be considerable.

Not very new, but a very slick video nonetheless! Will it work? I am not so sure whether "just engineering" applies in this case. The array of antenna's required is quite significant to compensate for beam losses. Wall plug efficiency is not that high therefore, then again.. solar energy is for free almost in the future so who cares.. let's go for it! :)

"The metamaterial aperature is only 40 centimeters long and it doesn't move. It's a circuit-board-like structure consisting of two copper plates separated by a piece of plastic. One of the plates is etched with repeating boxy structures, units about 2 millimeters long that permit different lengths of microwaves to pass through. Scanning the scene at various microwave frequencies allows the computer to capture all the information necessary to reproduce a scene."

where is Luzi's comment when one needs it ???

A scientist in the US is arguing that the vacuum should behave as a metamaterial at high magnetic fields. Such magnetic fields were probably present in the early universe, and therefore he suggests that it may be possible to test the prediction by observing the cosmic microwave background (CMB) radiation - a relic of the early universe that can be observed today.

Devices made from resonating graphene "drums" could be used as microwave amplifiers and memory chips in quantum computers. So say researchers at the Kavli Institute of Nanoscience at the Delft University of Technology in the Netherlands, who are the first to demonstrate optomechanical coupling between a mechanical resonator and a superconducting microwave cavity.

interesting paper for wireless energy transmission ... Duncan have a look ...

Yeah, its nice to see some research into semiconductors which aren't silicon. This paper would be useful for us if we wanted to do a study of the efficiency of the DC to microwave conversion systems for SPS.

"Our system of five clocks connects with an unprecedented consistency the optical and the microwave worlds." Interesting?

We present the design and experimental implementation of a power harvesting metamaterial. A maximum of 36.8% of the incident power from a 900 MHz signal is experimentally rectified by an array of metamaterial unit cells. We demonstrate that the maximum harvested power occurs for a resistive load close to 70 Ω in both simulation and experiment.

More developments in the laser filamentation community. Makes me wonder again about Christophe's ideas for a space-formed filament as new and efficient microwave waveguide.

coooool !

"Within a few years we will see the first true prototype of a spaceship that will take us between worlds," Worden said. this sounds to me a bit too much like Pete Worden :-) but I really like this one :-) One of those billionaires might be Google's Larry Page, who is keenly interested in space travel and NASA Ames's research. "Larry asked me a couple weeks ago how much it would cost to send people one way to Mars and I told him $10 billion, and his response was, 'Can you get it down to 1 or 2 billion?,'" Worden told the Long Now audience. "So now we're starting to get a little argument over the price."

The scientific rationale behind it is that at km-depth there could be a) water resources (which could support a biosphere) and b) understand the formation of Mars. I would argue that an efficient drilling (robot) is also valuable for possible developing underground habitation (caves) at some point. This paper mentions two drilling concepts, but we could come up with many more (bio-inspired) probably. Daniel already came up with a nice one.. microwave drilling Also, the NASA InSight probe to Mars in 2016 is using a DLR-designed 'Mole' drill that is designed to reach a depth of... 5 meters

In this case I was thinking more about a smaller and controlled digging effort.. not ablating a football field sized hole

Nice one! plenty of examples in nature for this

Mitsubishi Heavy Industries said Friday that it has succeeded in transmitting 10 kW of power through 500 m. An announcement that comes just after JAXA scientists reported one more breakthrough in the quest for Space Solar Power Systems (http://phys.org/news/2015-03-japan-space-scientists-wireless-energy.html). One step closer to Power Generation from Space/

from the press release (https://www.mhi-global.com/news/story/1503121879.html) "10 kilowatts (kW) of power was sent from a transmitting unit by microwave. The reception of power was confirmed at a receiver unit located at a distance of 500 meters (m) away by the illumination of LED lights, using part of power transmitted". So 10kW of transmission to light a few efficient LED lights??? In a 2011 report (https://www.mhi-global.com/company/technology/review/pdf/e484/e484017.pdf), MHI estimated this would generate the same electricity output as a 400-megawatt thermal plant - or enough to serve more than 150,000 homes during peak hours. The price? The same as publicly supplied power, according to its calculations. There are no results to boost these claims however. The main work they do now is focused on beam steering control. I guess the real application in mind is more targeted to terrestrial applications, eg wireless highway charging (http://www.bbc.com/future/story/20120312-wireless-highway-to-charge-cars). With the distances so much shorter, leading to much smaller antenna's and rectenna's this makes much more sense to me to develop.

An intelligent (that is, self-adaptive) cloak driven by deep learning. Quite cool, eh? Something we can get inspired by?