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Radio Waves spread into space

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The Sounds of Pulsars A pulsar is a highly magnetised neutron star, with a radius of 10-15 km, having somewhat greater mass than the Sun which has a radius of approximately 1 million km. Radiation is beamed out along the magnetic poles and pulses of radiation are received as the beam crosses the Earth, in the same manner as the beam from a lighthouse causes flashes. Being enormous cosmic flywheels with a tick attached, they make some of the best clocks known to mankind. These sounds directly correspond to the radio-waves emitted by the brightest pulsars in the sky as received by some of the largest radio telescopes in the world.

Source d'inspiration pour les passionnés de belles images : Les photographes exposent leurs photos DarQroom Not yet a member? Sign in Your Cart ( 0 ) English Images Advanced search Photos Sélectionnez une catégorie Venise Mars09 247.jpg Karine Mahiout Italie 130226pvc161802.jpg Gilbert Schmitt Essai de galerie : voyage d'étude PVC DR - Marmotte se réchauffant (été 2011 photo ph.van der Hoeven).jpg Philippe Van Der Hoeven FAUNE ALPESTRE... Manchots royaux au petit matin Géorgie du sud Pascal Cocco Géorgie du sud,antarctique Sauvage,Grandiose Daniel Heute Musée de la Marine Brest Dos_nus Bernard Delhalle Dos Nus Apples-201012-0144.tif Marc Burkhalter Le Bourke Photographie Au delà du miroir Gerard Delahaye créations DSC_6613.jpg Pascal Rivière My new portfolio costarica-0407.jpg Patrick B Les colibris du Costa Rica Francis Bernard NORVEGE IMG_0167_fhdr.jpg Salaun Jeremy chokito DSC_8143.png Bourgeon Jules NCRC Latricières Chambertin, 2008 Martin Charlyne portfolio IMG_3972.tif David Guenard LONG EXPOSURE The barber Amaury Paris LIVING IN DELHI Dominique Voirol Paysages vn0012.tif Monsieur KLEIN Support

FREQUENCY MODULATION - PART I - BASIC PRINCIPLES Scientists Now Know: We're From Sagittarius Dwarf Galaxy! Scientists Now Know: We're Not From Here! Summary & comments by Dan Eden for Viewzone "This first full-sky map of Sagittarius shows its extensive interaction with the Milky Way," Majewski said. "Both stars and star clusters now in the outer parts of the Milky Way have been 'stolen' from Sagittarius as the gravitational forces of the Milky Way nibbled away at its dwarf companion. This one vivid example shows that the Milky Way grows by eating its smaller neighbors." The study's map of M giants depicts 2 billion years of Sagittarius stripping by the Milky Way, and suggests that Sagittarius has reached a critical phase in what had been a slow dance of death. "After slow, continuous gnawing by the Milky Way, Sagittarius has been whittled down to the point that it cannot hold itself together much longer," said 2MASS Science Team member and study co-author Martin Weinberg of the University of Massachusetts. Does this mean we are at a unique moment in the life of our galaxy? From Dan Eden: Hi Dan,

crowfunding créativité Los recortes generalizados por la crisis han sido, paradójicamente, un caldo de cultivo idóneo para el desarrollo y la multiplicación de plataformas de crowdfunding, una forma de financiación a través de Internet en la que personas que no se conocen entre sí aportan dinero para que un determinado proyecto se convierta en realidad. “La gente quiere seguir consumiendo cultura, y ahora se le ofrece la posibilidad de ser parte de los proyectos de la gente a la que admira”, cuenta Jonás Sala, quien utilizó esta fórmula para realizar un documental. Cuando Jonás y su hermano Adriá buscaron ayudas para sacar adelante su proyecto, en otoño de 2009, se dieron de bruces con una realidad económica poco dispuesta a apoyar a creadores desconocidos. Fue entonces cuando, gracias a su padre, Joan, supieron de la existencia del crowdfunding (del inglés “financiación por la multitud”, que algunos traducen como micromecenazgo). Y no lo dudaron: lo suyo era la gestión cultural.

Sdrsharp+orbitron Quark Star (update) Some of the strange stuff that is coming out about quark stars: 1) that quark stars may be connected to dark matter (or even dark energy?) Some dark matter might just be “strangelets” roaming the cosmos, blasted free from quark stars: or 2) That some smaller sized black holes may actually be quark stars: “Some black holes may actually be ‘quark stars’:” or 3) The light given off by a quark star is called bremsstrahlung emissions. “quark star: gives off dim light (called bremsstrahlung emission), emitted by a thin layer of electrons on its surface:” or 4) It takes about 1.6 minutes to from a quark star from a neutron star. Like this: Like Loading...

ESAAB AVA All your RFz Belong to Me: Hacking the Wireless World with GNU Radio - Balint Seeber Darkest exoplanet spotted by astronomers 12 August 2011Last updated at 11:09 By Jason Palmer Science and technology reporter, BBC News TrES-2b is literally darker, on average, than coal A dark alien world, blacker than coal, has been spotted by astronomers. The Jupiter-sized planet is orbiting its star at a distance of just five million km, and is likely to be at a temperature of some 1200C. The planet may be too hot to support reflective clouds like those we see in our own Solar System, but even that would not explain why it is so dark. The research will be published in the journal Monthly Notices of the Royal Astronomical Society. The planet, called TrES-2b, is so named because it was first spotted by the Trans-Atlantic Exoplanet Survey in 2006. It also lies in the field of view of the Kepler space telescope, whose primary mission is to spot exoplanets using extremely sensitive brightness measurements as far-flung worlds pass in front of their host stars. 'Exotic chemistry' Continue reading the main story

blog » the notebook of cartographer zachary forest johnson Binning is a general term for grouping a dataset of N values into less than N discrete groups. These groups/bins may be spatial, temporal, or otherwise attribute-based. In this post I’m only talking about spatial (long-lat) and 2-dimensional attribute-based (scatterplot) bins. If you’re just after that sweet honey that is my code, bear down on my Github repository for this project — hexbin-js. Rectangular binning The simplest 2D bin is rectangular. The above is a shot from a little example I produced on jsFiddle, while learning Mike Bostock’s fantastic D3 JavaScript library for HTML and SVG data-binding and visualization. Binning can be good for both the users and the creators/developers of static or interactive thematic maps or other visualizations. In the above image (from Antaeus Concepts) the data points are represented in black, and due to overlap the true concentration/density distribution is indiscernible from the graphic. Hexagonal binning Adler writes, Hex history and theory

Testing the APM 2.5 Loiter Mode The Unsolved Mystery of Saturn's Hexagon -4 Times the Size of Earth "Cassini is indebted to Voyager for its many fascinating discoveries and for pavingthe way for Cassini," says Linda Spilker, Cassini project scientist at JPL, who started her career working on Voyager from 1977 to 1989. "On Cassini, we still compare our data to Voyager's and proudly build on Voyager's heritage." But the Voyager Mission left a few mysteries that Cassini has not yet solved. One of the most perplexing mysteries is Saturn's hexagpn. NASA scientists first spotted a hexagonal weather pattern when they stitched together Voyager images of Saturn's north pole. Cassini has obtained higher-resolution pictures of the hexagon – which tells scientists it's a remarkably stable wave in one of the jet streams that remains 30 years later – but scientists are still not sure what forces maintain the object. After the sunlight faded, darkness shrouded the north pole for 15 years. The hexagon was originally discovered in images taken by the Voyager spacecraft in the early 1980s.

Geometric Constructions This is a web version of a teacher's workshop presented at Bridges 2004Appeared in: Bridges for Teachers, Teachers for Bridges, 2004 Workshop Book, Mara Alagic and Reza Sarhangi eds., pp. 31-42. “Slide-Together” Geometric Paper Constructions George W. Hart Computer Science Dept. Stony Brook University Abstract Seven paper construction projects provide students with experience exploring properties and relationships of two-dimensional and three-dimensional geometric figures. “Slide-togethers” based on squares, triangles, pentagons, and decagons Introduction This activity consists of seven attractive constructions which are fun and relatively easy to make because one simply cuts out paper pieces and slides them together. Each “slide-together” is made from identical copies of a single type of regular polygon (e.g., just squares or just triangles) with slits cut at the proper locations. “Slide-togethers” based on hexagons, decagrams, and pentagrams