astroengine writes "The idea of slingshotting a manned spacecraft around Mars isn't a new one. In the 1960's, NASA carried out a feasibility study into an 800-day flyby mission to the Red Planet. And it would have been awesome. AT&T/Bellcomm mathematician A. A. VanderVeen was working for NASA in 1967 and came up with 5 possible launch opportunities between 1978 and 1986 — two windows in 1979 and 1983 provided the shortest transit time between the planets. But launch mass and fuel requirements were a constant issue. So VanderVeen turned to physics to find an elegant, and scientifically exciting, solution: add a Venus flyby to the Mars trip. Mars, Earth, and Venus align with the sun five times every 32 years, but Venus and Mars alignments happen more frequently making double (Earth-Venus-Mars-Earth) or even triple (Earth-Venus-Mars-Venus-Earth) flybys a viable mission. Unfortunately, the flyby never happened."
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willith writes "I spent two days at NASA's Neutral Buoyancy Laboratory in Houston, watching astronauts dive and getting a thorough tour of the facility. The largest indoor pool in the world contains 6.2M gallons of water and is filled with life-size replicas of International Space Station modules (though at 202'x101' and 40' deep, it isn't nearly enough to hold the entire station). Every spacewalk requires a huge amount of rehearsal, and that rehearsal is done right here in this pool. I talk at length with divers, astronauts, test coordinators, and test directors about how the facility works and what it takes to train folks to work in spacesuits. I also get to talk about the NBL's commercial future, and what's next for the big pool. Plus, lots and lots of pictures!"
Hugh Pickens writes writes "Science Daily Headlines reports that researchers have applied a recently developed technique to directly measure the polarization states of light overcoming some important challenges of Heisenberg's famous Uncertainty Principle and demonstrating that it is possible to measure key related variables, known as 'conjugate' variables, of a quantum particle or state directly. Such direct measurements of the wave-function had long seemed impossible because of a key tenet of the uncertainty principle — the idea that certain properties of a quantum system could be known only poorly if certain other related properties were known with precision. 'The reason it wasn't thought possible to measure two conjugate variables directly was because measuring one would destroy the wave-function before the other one could be measured,' says co-author Jonathan Leach. The direct measurement technique employs a 'trick' to measure the first property in such a way that the system is not disturbed significantly and information about the second property can still be obtained. This careful measurement relies on the 'weak measurement' of the first property followed by a 'strong measurement' of the second property. First described 25 years ago, weak measurement requires that the coupling between the system and what is used to measure it be, as its name suggests, 'weak,' which means that the system is barely disturbed in the measurement process. The downside of this type of measurement is that a single measurement only provides a small amount of information, and to get an accurate readout, the process has to be repeated multiple times and the average taken. Researchers passed polarized light through two crystals of differing thicknesses: the first, a very thin crystal that 'weakly' measures the horizontal and vertical polarization state; the second, a much thicker crystal that 'strongly' measures the diagonal and anti-diagonal polarization state. As the first measurement was performed weakly, the system is not significantly disturbed, and therefore, information gained from the second measurement was still valid. This process is repeated several times to build up accurate statistics. Putting all of this together gives a full, direct characterization of the polarization states of the light."
terbeaux writes "The fact that Rep Ed Orcutt (R — WA) wants to tax bicycle use is not extraordinary. The representative's irrational conviction is. SeattleBikeBlog has confirmed reports that Orcutt does not feel bicycling is environmentally friendly because the activity causes cyclists to have 'an increased heart rate and respiration.' When they contacted him he clarified that 'You would be giving off more CO2 if you are riding a bike than driving in a car...' Cascade blog has posted the full exchange between Rep Ed Orcutt and a citizen concerned about the new tax."
An anonymous reader writes in with news of a breakthrough in the treatment of HIV. "A baby born with the AIDS virus two years ago in Mississippi who was put on antiretroviral therapy within hours of birth appears to have been cured of the infection, researchers said Sunday at a scientific conference in Atlanta. Whether the cure is complete and permanent, or only partial and long-lasting, is not certain. Either way, the highly unusual case raises hope for the more than 300,000 babies born with the infection around the world each year."
Hugh Pickens writes writes "The first dogs descended from wolves about 14,000 years ago but according to Brian Hare and Vanessa Woods humans didn't domesticate dogs — dogs sought out humans and domesticated us. Humans have a long history of eradicating wolves, rather than trying to adopt them which raises the question: How was the wolf tolerated by humans long enough to evolve into the domestic dog? 'The short version is that we often think of evolution as being the survival of the fittest, where the strong and the dominant survive and the soft and weak perish. But essentially, far from the survival of the leanest and meanest, the success of dogs comes down to survival of the friendliest.' Most likely, it was wolves that approached us, not the other way around, probably while they were scavenging around garbage dumps on the edge of human settlements. The wolves that were bold but aggressive would have been killed by humans, and so only the ones that were bold and friendly would have been tolerated. In a few generations, these friendly wolves became distinctive from their more aggressive relatives with splotchy coats, floppy ears, wagging tails. But the changes did not just affect their looks but their psychology. Protodogs evolved the ability to read human gestures. 'As dog owners, we take for granted that we can point to a ball or toy and our dog will bound off to get it,' write Hare and Woods. 'But the ability of dogs to read human gestures is remarkable. Even our closest relatives — chimpanzees and bonobos — can't read our gestures as readily as dogs can. 'With this new ability, these protodogs were worth knowing. People who had dogs during a hunt would likely have had an advantage over those who didn't. Finally when times were tough, dogs could have served as an emergency food supply and once humans realized the usefulness of keeping dogs as emergency food, it was not a huge jump to realize plants could be used in a similar way.' This is the secret to the genius of dogs: It's when dogs join forces with us that they become special," conclude Hare and Woods. 'Dogs may even have been the catalyst for our civilization.'"