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Astronomers Solve the Mystery of 'Hanny's Voorwerp' 123 123

KentuckyFC writes "In 2007, a Dutch school teacher named Hanny van Arkel discovered a huge blob of green-glowing gas while combing though images to classify galaxies. Hanny's Voorwerp (meaning Hanny's object in Dutch) is astounding because astronomers have never seen anything like it. Although galactic in scale, it is clearly not a galaxy because it does not contain any stars. That raises an obvious question: what is causing the gas to glow? Now a new survey of the region of sky seems to have solved the problem. The Voorwerp lies close to a spiral galaxy which astronomers now say hides a massive black hole at its center. The infall of matter into the black hole generates a cone of radiation emitted in a specific direction. The great cloud of gas that is Hanny's Voorwerp just happens to be in the firing line, ionizing the gas and causing it to glow green. That lays to rest an earlier theory that the cloud was reflecting an echo of light from a short galactic flare up that occurred 10,000 years ago. It also explains why Voorwerps are so rare: these radiation cones are highly directional so only occasionally do unlucky gas clouds get caught in the crossfire."

Police Investigating Virtual Furniture Theft 103 Screenshot-sm 103

krou writes "Finnish police are involved in the investigation of up to 400 cases of theft from virtual world Habbo Hotel, with some users reporting the loss of up to €1000 of virtual furniture and other items. Users were targeted using a phishing scam that used fake webpages to capture usernames and passwords. There is no mention as to whether or not the thieves made off with the bath towels, gowns, shampoo bottles, and soaps."

Study Claims Cellphones Implicated In Bee Loss 542 542

krou passes along word from that researchers from Chandigarh's Punjab University claim that they have proven mobile phones could explain Colony Collapse Disorder. "They set up a controlled experiment in Punjab earlier this year comparing the behavior and productivity of bees in two hives — one fitted with two mobile telephones which were powered on for two 15-minute sessions per day for three months. The other had dummy models installed. After three months the researchers recorded a dramatic decline in the size of the hive fitted with the mobile phone, a significant reduction in the number of eggs laid by the queen bee. The bees also stopped producing honey. The queen bee in the 'mobile' hive produced fewer than half of those created by her counterpart in the normal hive. They also found a dramatic decline in the number of worker bees returning to the hive after collecting pollen." We've talked about the honeybee problem before. Today's article quotes a British bee specialist who dismisses talk of cellphone radiation having anything to do with the problem.

Comment Re:Unfair? Maybe. Overdue? Definitely. (Score 1) 67 67

That's cool! I appreciate your concerns about Constellation. There's a lot of bad press and unfortunate misinformation floating around, yet despite that it's extremely important to listen to the criticism.

Ares may be a polished turd, but it's the best turd ever built to date. It has the most thorough fault detection, caution and warning and abort systems of any human rated launch vehicle. First stage is reusable, just like Shuttle solid rocket motors. Hypergol and cryogenic handling is safer and more efficient than legacy systems. Block II first stages may even eliminate hydrazine completely in favor of electromechanial thrust vector control actuators. If first stage leaks, at a case or nozzle joint, the resulting side thrust can be easily countered until the end of first stage burn. Since it's not a side-mount, the escaping gas won't harm anything. We've got fault detection in both the forward and aft skirt in case of leaks on either end of the case.

1. "Black zones": In the event of an uncontained failure, the launch abort system can escape cleanly even near max Q. Ares has no "black zones", despite what the tinfoil crew may claim. Escaping from an uncontained failure is not just a requirement for solid boosters; liquid engines can blow up, too.

2. Thermal Protection Systems (TPS): Orion has sufficient thermal protection to make a worst case straight in ballistic re-entry at any point during ascent, and the capsule floats well enough and has enough life support on board to safely come down anywhere on the planet. The competing lightweight commercial capsules, launched on EELV's, do not have TPS scaled for re-entry from a lunar mission, and it's unknown if they'd even survive the heat of a ballstic North Atlantic re-entry.

3. Failsafe insertion: Ares inserts Orion in an elliptical orbit with a negative perigee altitude. If something goes horribly wrong on Orion, they come down safely in half a rev. Contrast this with the CCTS approach, naively copied from commercial satellite launching - they put their capsule (and upper stage) into a long lifetime circular orbit. If the capsule has a failure, they're stuck up there. Depending on which version you look at, the commercial crew aren't even wearing launch and entry suits.

Ares I is the safest rocket ever built. I'm proud to be a part of it. Regardless what goes on at the executive level, Constellation remains the Program of Record and it will literally take an act of Congress to kill it. Until then, Obama's proposed budget is just that: proposed.

Comment Re:Unfair? Maybe. Overdue? Definitely. (Score 1) 67 67

no possibility of practical stage re-use.

The solid rocket motors are reusable. I'm sorry, but you're wrong.

Once the rocket segments have been poured and cured they're effectively "loaded" and have to be handled with great care to make sure there's no possibility of accidental ignition -- something totally avoided with liquid fuel rockets where the oxidiser and fuel are kept completely separately

Red herring argument. Cryogenic liquid oxygen is way more dangerous and expensive to handle than loaded solid propellant.

I'm just glad that the Ares-I got cancelled before it killed yet more astronauts.

It isn't canceled. Constellation won't be canceled unless congress approves the Obama budget. Unless that happens, NASA is required by law to continue working the program of record. Just curious: which space industry do you work in? Your British spelling makes me curious :)

Comment Re:Unfair? Maybe. Overdue? Definitely. (Score 1) 67 67

CxP takes Shuttle and other legacy technology and tries to make it safer than any of the previous systems ever were. Apollo and Shuttle were developed without any idea what the reliability would be or what the risks were. Constellation was given the go-ahead with the understanding that it would be made much MUCH safer. Unfortunately, we actually tried to make it that much safer and the peanut gallery wondered why it was costing so much.

Students Show a Dramatic Drop In Empathy 659 659

MotorMachineMercenar writes "Several news sources report that today's college students show a precipitous drop in empathy (here's MSNBC's take). The study of 14,000 students shows that students since the year 2000 had 40% less empathy than those 20 and 30 years before them. The article lays out a laundry list of culprits, from child-rearing practices and the self-help movement, to video games and social media, to a free-market economy and income inequality. There's also a link so you can test your very own level of narcissism. Let's hope the Slashdot crowd doesn't break the empathy counter on the downside."

Comment Re:Constellation was a joke (Score 2, Interesting) 67 67

Funny thing is, the baselined CCDev trajectories are standard commercial satellite trajectories. The EELV upper stage inserts the crew capsule directly into a circular decay for at least a week. This was rationalized away by requiring scale up RCS on the crew capsule with enough delta-V to deorbit the capsule in the event of a service module engine failure. To their credit, Boeing's commercial capsule does this. Can't say for sure about Lockmart or Space-X.

Comment Re:Constellation was a joke (Score 2, Interesting) 67 67

ULA has no idea what they're getting into, trying to man-rate Delta and Atlas. Yet even as an Ares I engineer I'm helping them to get there. As for Space-X, they're the Moller Skycar of the spaceflight business. In the past, even mentioning Direct would have gotten you dismissed as a tinfoil hatter yourself, but actually, one of the proposed HLV's to come out of Hanley's study last week had 4 segment solids with an SSME or RS-68 core. Very Direct-like, but without the woo.

Comment Re:Not to sound like a tinfoil hat... (Score 1) 67 67

Obama *is* a darn politician. NASA's charter is not to buy off-the-shelf hardware, but rather to R&D low technology readiness level (TRL) projects and to and operate missions that no commercial entity would consider. I work in a small section of CxP, and coincidentally have also been an advisor to some CCTS work. I can assure you, NASA (and our contractors, of course) have our human spaceflight shit together way more than ULA/Boeing/Space-X et. al. In fact, ULA would even be attempting to human-rate their launch vehicles if it wasn't for NASA funding them to do the work! Private (that is, commercial) industry is not anywhere near ready for human spaceflight. Oh, and you know those

When Mistakes Improve Performance 222 222

jd and other readers pointed out BBC coverage of research into "stochastic" CPUs that allow communication errors in order to reap benefits in performance and power usage. "Professor Rakesh Kumar at the University of Illinois has produced research showing that allowing communication errors between microprocessor components and then making the software more robust will actually result in chips that are faster and yet require less power. His argument is that at the current scale, errors in transmission occur anyway and that the efforts of chip manufacturers to hide these to create the illusion of perfect reliability simply introduces a lot of unnecessary expense, demands excessive power, and deoptimises the design. He favors a new architecture, that he calls the 'stochastic processor,' which is designed to handle data corruption and error recovery gracefully. He believes he has shown such a design would work and that it would permit Moore's Law to continue to operate into the foreseeable future. However, this is not the first time someone has tried to fundamentally revolutionize the CPU. The Transputer, the AMULET, the FM8501, the iWARP, and the Crusoe were all supposed to be game-changers but died cold, lonely deaths instead — and those were far closer to design philosophies programmers are currently familiar with. Modern software simply isn't written with the level of reliability the stochastic processor requires (and many software packages are too big and too complex to port), and the volume of available software frequently makes or breaks new designs. Will this be 'interesting but dead-end' research, or will Professor Kumar pull off a CPU architectural revolution really not seen since the microprocessor was designed?"

Fools ignore complexity. Pragmatists suffer it. Some can avoid it. Geniuses remove it. -- Perlis's Programming Proverb #58, SIGPLAN Notices, Sept. 1982