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Space

SpaceX's Grasshopper VTVL Finally Jumps Its Own Height 111

cylonlover writes "The SpaceX Grasshopper vertical takeoff vertical landing (VTVL) testbed has successfully flown to a height of 40 meters (131 ft), hovered for a bit and subsequently landed in a picture perfect test on December 17, 2012. The Grasshopper had previously taken two hops to less than 6 m (20 ft) in height, but the latest test was the first that saw it reach an altitude taller than the rocket itself, which is a modified Falcon 9 orbital launch vehicle. The flight lasted 29 seconds from launch to landing, and carried a 1.8 m (6 ft) cowboy dummy to give an indication of scale."
Science

Catfish Strands Itself To Kill Pigeons 115

A reader writes "In Southwestern France, a group of fish have learned how to kill birds. As the River Tarn winds through the city of Albi, it contains a small gravel island where pigeons gather to clean and bathe. And patrolling the island are European catfish—1 to 1.5 meters long, and the largest freshwater fish on the continent. These particular catfish have taken to lunging out of the water, grabbing a pigeon, and then wriggling back into the water to swallow their prey. In the process, they temporarily strand themselves on land for a few seconds. Other aquatic hunters strand themselves in a similar way, including bottlenose dolphins from South Carolina, which drive small fish onto beaches, and Argentinian killer whales, which swim onto beaches to snag resting sealions. The behavior of the Tarn catfishes is so similar that Julien Cucherousset from Paul Sabatier University in Toulouse describes them as 'freshwater killer whales.'"

Comment Re:The problem with CFC (Score 1) 211

not only that, but it isn't something that you keep using, so even if civilization continues, CFC's probably won't (at high levels). The consequences of high atmospheric CFC's are enough to push them out of use. It'll be like high powered omnidirectional TV and radio signals. Those stopped too, yet we continue.

Comment Re:Lots of work has been done here (Score 1) 62

LEDs will still have a pretty broad spectral response so you'd have overlap, and need quite a bit of gain. Try one of the taos colour sensing chips, those do RGB+all with programmable gain and digital output, it'll make the project pretty simple and much more repeatable. you can also do one clear NIR phototransistor with selectable filters for colours. That'd be manageable. For my project, I am using, currently, a clear phototransistor and illuminating the target with a specific LED colour. I think someone has done something pretty similar (but reflection rather than transmission) on instructables too, but I can't dig it up.

Comment Re:Hah! Take that, my bank! (Score 1) 497

TD bank in canada: 5-8 letters, no symbols. Sure you have to answer a few (random 3 of 5) quiz-of-your-life-history questions after, but really. http://www.tdcanadatrust.com/products-services/banking/electronic-banking/faq-idplus.jsp Passwords must: - be 5 to 8 characters in length - not contain spaces or special characters (e.g. #, &, @)
The Internet

Where the Candidates Stand On Net Neutrality 420

nmpost writes "Net neutrality is one of the biggest issues with regard to the internet today. At the heart of the issues is how much control ISPs will be allowed to have over their networks. Each candidate has come out with a strong position on the matter, and whoever wins will have a drastic effect on the future of the internet. Barack Obama has been a proponent of net neutrality. Under his watch, the FCC has implemented net neutrality rules. These restrictions did not apply to wireless networks, though; a gaping loophole that will be problematic in the future, as mobile internet is exploding in popularity. Until it is addressed, Obama can only be given a barely passing grade with regard to net neutrality. Republican Presidential candidate Mitt Romney has come down on the other side of the issue. The former Massachusetts governor strongly opposes net neutrality. According to Politico, Romney believes net neutrality will restrict ISPs, and that they alone should govern their networks. The governor has stated that he wants as little regulation of the internet as possible."

Comment Re:It is a RO membrane, just a really good one (Score 5, Informative) 303

The abstract: "We show that nanometer-scale pores in single-layer freestanding graphene can effectively filter NaCl salt from water. Using classical molecular dynamics, we report the desalination performance of such membranes as a function of pore size, chemical functionalization, and applied pressure. Our results indicate that the membrane’s ability to prevent the salt passage depends critically on pore diameter with adequately sized pores allowing for water flow while blocking ions. Further, an investigation into the role of chemical functional groups bonded to the edges of graphene pores suggests that commonly occurring hydroxyl groups can roughly double the water flux thanks to their hydrophilic character. The increase in water flux comes at the expense of less consistent salt rejection performance, which we attribute to the ability of hydroxyl functional groups to substitute for water molecules in the hydration shell of the ions. Overall, our results indicate that the water permeability of this material is several orders of magnitude higher than conventional reverse osmosis membranes, and that nanoporous graphene may have a valuable role to play for water purification." Emphasis added for why, and the introduced problem

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