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It has been known for a century that electromagnetic fields can transport not only energy and linear momentum but also angular momentum. However, it was not until twenty years ago, with the discovery in laser optics of experimental techniques for the generation, detection and manipulation of photons in well-defined, pure orbital angular momentum (OAM) states, that twisted light and its pertinent optical vorticity and phase singularities began to come into widespread use in science and technology. We have now shown experimentally how OAM and vorticity can be readily imparted onto radio beams. Our results extend those of earlier experiments on angular momentum and vorticity in radio in that we used a single antenna and reflector to directly generate twisted radio beams and verified that their topological properties agree with theoretical predictions. This opens the possibility to work with photon OAM at frequencies low enough to allow the use of antennas and digital signal processing, thus enabling software controlled experimentation also with first-order quantities, and not only second (and higher) order quantities as in optics-type experiments. Since the OAM state space is infinite, our findings provide new tools for achieving high efficiency in radio communications and radar technology.

and how can we use this?

We show numerically that vector antenna arrays can generate radio beams that exhibit spin and orbital angular momentum characteristics similar to those of helical Laguerre-Gauss laser beams in paraxial optics. For low frequencies (<~1 GHz), digital techni

incredible!!!

"We examine the possibility that Fast Radio Bursts (FRBs) originate from the activity of extragalactic civilizations"

part of the bbc's citizen sciene thingy 'so you want to be a scientist. it's like a game show for science experiments if you're not familiar. the bookmark will take you to the online participation part of one of the experiments selected. here's the main page. http://www.bbc.co.uk/radio4/features/sywtbas/ "This experiment is being run by citizen scientist Izzy Thomlinson for BBC Radio 4's So You Want To Be A Scientist?. It aims to find out what you think about unpleasant sounds. Please read the following statement and click Take Part Now! if you agree to participate."

In a feat never before observed, a newly discovered pulsar shifts back and forth between emitting X-rays and radio waves. The discovery represents a long-sought "middle" phase in the life of these powerful objects.

Team leader Professor Steven Tingay, Director of the MWA at Curtin University and Chief Investigator in the Australian Research Council Centre for All-sky Astrophysics (CAASTRO) said the MWA will be able to detect the space junk by listening in to the radio signals generated by stations including popular youth network Triple J.

Strange and exotic cityscapes. Desolate wilderness areas. Dogs that look like wookies. Flickr, one of the world's largest photo sharing services, sees it all. And, now, Flickr's image recognition technology can categorize more than 11 billion photos like these. And it does it automatically. It's called "Magic View." Magical deep learning! Buzzword attack!

You're forgetting power usage. GPUs need 1000 hamster wheels worth of power while FPGAs can run on a potato. Since space applications are highly power limited, putting any kind of GPU monster in orbit or on a rover is failed idea from the start. Also in FPGAs if a gate burns out from radiation you can just reprogram around it. Looking for seals offline in high res images is indeed definitely a GPU task.... for now.

The discussion of how to make FPGA hardware acceleration solutions easier to use for the 'layman' is starting btw http://reconfigurablecomputing4themasses.net/.

Duncan and Xurxo have a look at this - just discussed today :-)

Hundreds of hidden nearby galaxies have been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor. Despite being just 250 million light years from Earth-very close in astronomical terms-the new galaxies had been hidden from view until now by our own galaxy, the Milky Way. Using CSIRO's Parkes radio telescope equipped with an innovative receiver, an international team of scientists were able to see through the stars and dust of the Milky Way, into a previously unexplored region of space. The discovery may help to explain the Great Attractor region, which appears to be drawing the Milky Way and hundreds of thousands of other galaxies towards it with a gravitational force equivalent to a million billion Suns. Lead author Professor Lister Staveley-Smith, from The University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR), said the team found 883 galaxies, a third of which had never been seen before. "The Milky Way is very beautiful of course and it's very interesting to study our own galaxy but it completely blocks out the view of the more distant galaxies behind it," he said. Professor Staveley-Smith said scientists have been trying to get to the bottom of the mysterious Great Attractor since major deviations from universal expansion were first discovered in the 1970s and 1980s. "We don't actually understand what's causing this gravitational acceleration on the Milky Way or where it's coming from," he said. "We know that in this region there are a few very large collections of galaxies we call clusters or superclusters, and our whole Milky Way is moving towards them at more than two million kilometres per hour." The research identified several new structures that could help to explain the movement of the Milky Way, including three galaxy concentrations (named NW1, NW2 and NW3) and two new clusters (named CW1 and CW2).

Machine learning yields detection of 72 new fast radio bursts from distant galaxy. SETI folks are getting excited.

completely new cosmic phenomenon?

The final goodbye of a massive star collapsing to a black hole? http://www.sciencedaily.com/releases/2013/07/130705101626.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29

Abstract: The "Magnificent Seven" (M7) are a group of radio-quiet Isolated Neutron Stars (INSs) discovered in the soft X-rays through their purely thermal surface emission. Owing to the large inferred magnetic fields ($B\approx 10^{13}$ G), radiation from these sources is expected to be substantially polarised, independently on the mechanism actually responsible for the thermal emission.

An intermediate level discussion of those results by Scott Manley (Physicist, Kerbal Space Program YouTuber): https://www.youtube.com/watch?v=JGcvxg7jJTs

Combination of the radio occultation method plus change in the orbital plan in order to observe new target (the volcanic outgassing from Io satellite) by passing though the magnetosphere of Jupiter. It poses a challenge in the sensitivity of the electronics. Maybe it is accepted if the risk is low. Idea for the next GTOC challenge maybe? Optimising the cost on the electronics vs the frequency of passages?

Interesting. these guys are apparently gonna try developing pulsar navigation. They propose to solve the low apparent brightness problem using relatively complex signal processing and filtering to limit the antenna size etc. The say they've already had some promising results using ground based data. worth a science coffee perhaps?

Absolutely. Sante can you get in contact with them?

Sante? Luzi?

"A band of space hackers and engineers are trying to do something never done before - recover a 36 year old NASA spacecraft from the grips of deep space and time. With old NASA documents and Rockethub crowdfunding, a team led by Dennis Wingo and Keith Cowing is attempting to steer ISEE-3, later rechristened ICE, the International Cometary Explorer, back into an Earth orbit and return it to scientific operations. Dennis says, 'ISEE-3 can become a great teaching tool for future engineers and scientists helping with design and travel to Mars'. Only 40 days remain before the spacecraft will be out of range for recovery. A radio telescope is available, propulsion designs are in hand and the team is hoping for public support to provide the small amount needed to accomplish a very unique milestone in space exploration