Using dielectric materials as efficient EM radiators and receivers can scale down these antenna's to the chip level, reducing both weight and power consumption. The infamous internet-of-things one step closer. But could we also transmit power this way??
"In dielectric aerials, the medium has high permittivity, meaning that the velocity of the radio wave decreases as it enters the medium," said Dr Dhiraj Sinha, the paper's lead author. "What hasn't been known is how the dielectric medium results in emission of electromagnetic waves. This mystery has puzzled scientists and engineers for more than 60 years."
The researchers determined that the reason for this phenomenon is due to symmetry breaking of the electric field associated with the electron acceleration
The researchers found that by subjecting the piezoelectric thin films to an asymmetric excitation, the symmetry of the system is similarly broken, resulting in a corresponding symmetry breaking of the electric field, and the generation of electromagnetic radiation.
Even after reading this sentence: "NASA wants to put a photograph of your face on one of the remaining space shuttle missions and launch it into orbit." it's not clear to me what exactly they plan to do... anyone?
I guess it is a symbolic way of flying the space shuttle for the last time! as JAXA does it with your name - if you want to - for all their scientific missions.
Nice initiative indeed!
Wow, they even mentioned it in the news on the Polish radio yesterday... What I am curious is if they really take the physical (or at least digital) photo and name to the orbit, or is this just, as you called it, "symbolic" ...
A new technique might soon enable cosmologists to map the universe even when they can't pick out individual galaxies. If it works, researchers would be able to probe the structure of 500 times as much of the universe as they have studied so far.
With a purpose-built radio telescope, the approach could map as much as 50% of the observable universe far faster and cheaper than galaxy surveys can, Loeb says.
A computer simulation shows the transition from "fermionic" to "liquid" light.
The possibility of sending this type of "self-focused" light pulse long distances could be important for remote sensing applications, such as LIDAR, which uses laser light the way radar uses radio waves.
Not that I'm an expert in the field in any way, but there are two things I could think of:
1) possibility of bringing the payload back means that it can collect huge amounts of data which wouldn't be possible to be transferred via radio in reasonable time and/or you can bring back data you don't want to be intercepted by enemy
2) I remember reading somewhere that possibility of re-entry from orbit means you can strike any country without violating the airspace of the neighbouring countries.
As the project is now managed by military, a purely civil purpose can be safely ruled out in my opinion.
like the profiles ...
"The clearest evidence for the pulsar's existence was provided by computers operated by two volunteers: Vitaly Shiryaev, a Russian researcher who has a Ph.D. in radio physics; and Stacey Eastham, who does vehicle testing for the British government in Darwen. In his profile, Eastham says he's studying astronomy and physics on the side. He got involved in the Einstein @ Home project because he's interested in "anything space-like, and being able to be part of something like this is right up my street."
You mean: "then why don't we have super fast internet?" :-)
If you zoom the map in, it's actually way past Noordwijk. My quess is this could be attached somewhere near the naval radio station area? This remembered me the good old times of bike trips in the dunes, eh...
Scientists have used the National Science Foundation's Very Long Baseline Array (VLBA) radio-telescope system and NASA's Cassini spacecraft to measure the position of Saturn and its family of moons to within about a mile -- at a range of nearly a billion miles.
Guinness World Record breaking, "first radio amplifier operating at terahertz frequencies could lead to communications systems with much higher data rates, better radar, high-resolution imaging that could penetrate smoke and fog, and better ways of identifying dangerous substances, say the researchers who built it".
Built from HEMTs (High Electron Mobility Transistors) made of InP (Indium Phosphide), this is a new milestone on the road to the THz applications.
Related to our discussion on crowdfunding from Friday's science coffee.
(Another sad example of how Tony Abbott's policy negatively affects the Australian science community... )
A team of astronomers have resorted to raising funds through crowdsourcing to try and save an Australian telescope involved in mapping the Milky Way. The 22-metre diameter Mopra Radio Telescope, based near Coonabarabran in western New South Wales, is slated to be shut down by the end of the year after $110-million was slashed from CSIRO in last year's federal budget.