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SpaceX Tests Its Raptor Engine For Future Mars Flights (

Thelasko writes: Elon Musk is preparing to unveil his plans to colonize Mars at the 67th annual International Astronautical Congress tomorrow. As a tease to his lecture, he has released some details about the Raptor engine on Twitter, including pictures. Mr. Musk states that, "Production Raptor coal is specific impulse of 382 seconds and thrust of 3 MN (~310 metric tons) at 300 bar." He goes on to note that the specific impulse spec is at Mars ambient pressure. The Raptor interplanetary engine is designed for use with Space X's Mars Colonial Transporter craft. Musk notes that the "chamber pressure runs three times what's present in the Merlin engine currently used to power Falcon 9," according to TechCrunch. "Merlin has specific impulse of 282 seconds (311 seconds in the vacuum of space), and a relatively paltry 654 kilonewton (0.6 MN) at sea level, or 716 kN (0.7 MN) in a vacuum. You can view a picture of the "Mach diamonds" here, which are visible in the engine's exhaust.

Roller Coasters Could Help People Pass Kidney Stones, Says Study ( 46

An anonymous reader quotes a report from NBC News: Two researchers who took science to the amusement park say they've found that a thrilling roller coaster ride just might help people shake out pesky kidney stones. Dr. David Wartinger of Michigan State University said he'd heard patient after patient tell him about how they had passed kidney stones after riding one particular ride: the Big Thunder Mountain Railroad roller coaster at Walt Disney World in Orlando. He and a colleague, Dr. Marc Mitchell, had also seen some media reports about people who passed kidney stones while bungee jumping and riding roller coasters. So they decided to leave East Lansing to head to Orlando in the name of medical research. To simulate the human body as best they could, they made an artificial human kidney model out of clear silicone gel and loaded it up with real human kidney stones. They rode the roller coaster holding their kidney contraption between them in a backpack positioned at kidney height. They took 20 rides and noted what happened to each kidney stone. Riding in the back of the roller coaster train seemed to really knock the kidney stones out, they reported in The Journal of the American Osteopathic Association. "Front seating on the roller coaster resulted in a passage rate of four of 24," they wrote. "Rear seating on the roller coaster resulted in a passage rate of 23 of 36." They mainly tested the one roller coaster ride, and it's a fairly simple one. "The Big Thunder Mountain roller coaster is not a terribly dynamic ride," Wartinger said. "It's not very fast. It is not very tall. It makes sharp left and right turns that have some vibration." Wartinger suspects many different thrill rides would have the same effect. "It's not like there anything unique about this one coaster," he said. The pair have now run their test 200 more times and say the findings are consistent. Now they want to try other amusement park rides.

Study: Earth Is At Its Warmest In 120,000 Years ( 56

An anonymous reader quotes a report from Washington Post: As part of her doctoral dissertation at Stanford University, Carolyn Snyder, now a climate policy official at the U.S. Environmental Protection Agency, created a continuous 2 million year temperature record, much longer than a previous 22,000 year record. Snyder's temperature reconstruction, published Monday in the journal Nature, doesn't estimate temperature for a single year, but averages 5,000-year time periods going back a couple million years. Snyder based her reconstruction on 61 different sea surface temperature proxies from across the globe, such as ratios between magnesium and calcium, species makeup and acidity. But the further the study goes back in time, especially after half a million years, the fewer of those proxies are available, making the estimates less certain, she said. These are rough estimates with large margins of errors, she said. But she also found that the temperature changes correlated well to carbon dioxide levels. Temperatures averaged out over the most recent 5,000 years -- which includes the last 125 years or so of industrial emissions of heat-trapping gases -- are generally warmer than they have been since about 120,000 years ago or so, Snyder found. And two interglacial time periods, the one 120,000 years ago and another just about 2 million years ago, were the warmest Snyder tracked. They were about 3.6 degrees (2 degrees Celsius) warmer than the current 5,000-year average. Snyder said if climate factors are the same as in the past -- and that's a big if -- Earth is already committed to another 7 degrees or so (about 4 degrees Celsius) of warming over the next few thousand years. "This is based on what happened in the past, Snyder noted. "In the past it wasn't humans messing with the atmosphere."

Researcher Modifies Sieve of Eratosthenes To Work With Less Physical Memory Space ( 44

grcumb writes: Peruvian mathematician Harald Helfgott made his mark on the history of mathematics by solving Goldbach's weak conjecture, which states that every odd number greater than 7 can be expressed as the sum of three prime numbers. Now, according to Scientific American, he's found a better solution to the sieve of Eratosthenes: "In order to determine with this sieve all primes between 1 and 100, for example, one has to write down the list of numbers in numerical order and start crossing them out in a certain order: first, the multiples of 2 (except the 2); then, the multiples of 3, except the 3; and so on, starting by the next number that had not been crossed out. The numbers that survive this procedure will be the primes. The method can be formulated as an algorithm." But now, Helfgott has found a method to drastically reduce the amount of RAM required to run the algorithm: "Now, inspired by combined approaches to the analytical 100-year-old technique called the circle method, Helfgott was able to modify the sieve of Eratosthenes to work with less physical memory space. In mathematical terms: instead of needing a space N, now it is enough to have the cube root of N." So what will be the impact of this? Will we see cheaper, lower-power encryption devices? Or maybe quicker cracking times in brute force attacks? Mathematician Jean Carlos Cortissoz Iriarte of Cornell University and Los Andes University offers an analogy: "Let's pretend that you are a computer and that to store data in your memory you use sheets of paper. If to calculate the primes between 1 and 1,000,000, you need 200 reams of paper (10,000 sheets), and with the algorithm proposed by Helfgott you will only need one fifth of a ream (about 100 sheets)," he says.

China's Giant Radio Telescope Begins Searching For Signals From Space ( 41

Years of work and millions of dollars later, China finished its alien-hunting telescope in May this year. Now the country says its telescope has begun its operation. The company flipped the switch over the weekend, hoping to find signals from stars and galaxies -- and more importantly from extraterrestrial life. The telescope also illustrates China's growing ambition to stay among the frontrunners in space efforts. AP reports: Beijing has poured billions into such ambitious scientific projects as well as its military-backed space program, which saw the launch of China's second space station earlier this month. Measuring 500 metres in diameter, the radio telescope is nestled in a natural basin within a stunning landscape of lush green karst formations in southern Guizhou province. It took five years and $180 million to complete and surpasses that of the 300-meter Arecibo Observatory in Puerto Rico, a dish used in research on stars that led to a Nobel Prize. The official Xinhua News Agency said hundreds of astronomers and enthusiasts watched the launch of the Five-hundred-meter Aperture Spherical Telescope, or FAST, in the county of Pingtang. Researchers quoted by state media said FAST would search for gravitational waves, detect radio emissions from stars and galaxies and listen for signs of intelligent extraterrestrial life. "The ultimate goal of FAST is to discover the laws of the development of the universe," Qian Lei, an associate researcher with the National Astronomical Observatories of the Chinese Academy of Sciences, told state broadcaster CCTV. "In theory, if there is civilization in outer space, the radio signal it sends will be similar to the signal we can receive when a pulsar (spinning neutron star) is approaching us," Qian said.

Scientists Study How Non-Scientists Deny Climate Change ( 617

A new research paper suggest climate change opponents are "simulating coherence by conspiracism". Slashdot reader Layzej says the paper "examines this behavior at the aggregate level, but gives many examples where contradictory ideas are held by the same individual, and sometimes are presented within a single publication." From the paper: Claims that the globe "is cooling" can coexist with claims that the "observed warming is natural" and that "the human influence does not matter because warming is good for us". Coherence between these mutually contradictory opinions can only be achieved at a highly abstract level, namely that "something must be wrong" with the scientific evidence in order to justify a political position against climate change mitigation...

In a nutshell, the opposition to greenhouse gas emission cuts is the unifying and coherent position underlying all manifestations of climate science denial... Climate science denial is therefore perhaps best understood as a rational activity that replaces a coherent body of science with an incoherent and conspiracist body of pseudo-science for political reasons and with considerable political coherence and effectiveness.

"I think that people who deny basic science will continue to do so, no matter how contradictory their arguments may be," says one of the paper's authors, who suggests that the media should be wary of self-contradicting positions.

The Ig Nobel Awards Celebrate Their 26th First Annual Awards Ceremony ( 33

Thursday Harvard's Sanders Theatre hosted the 26th edition of the humorous research awards "that make people laugh, then think...intended to celebrate the unusual, honor the imaginative -- and spur people's interest in science, medicine, and technology." One of this year's winners actually lived as a goat, wearing prosthetic extensions on his arms and legs so he could travel the countryside with other goats. Long-time Slashdot reader tomhath writes: The Journal of Improbable announced these winners:

REPRODUCTION PRIZE [EGYPT] -- The late Ahmed Shafik, for studying the effects of wearing polyester, cotton, or wool trousers on the sex life of rats, and for conducting similar tests with human males.

ECONOMICS PRIZE [NEW ZEALAND, UK] -- Mark Avis, Sarah Forbes, and Shelagh Ferguson, for assessing the perceived personalities of rocks, from a sales and marketing perspective...

PEACE PRIZE [CANADA, USA] -- Gordon Pennycook, James Allan Cheyne, Nathaniel Barr, Derek Koehler, and Jonathan Fugelsang for their scholarly study called 'On the Reception and Detection of Pseudo-Profound Bullshit'...

PERCEPTION PRIZE [JAPAN] -- Atsuki Higashiyama and Kohei Adachi, for investigating whether things look different when you bend over and view them between your legs.

The Improable Research site lists the rest of this year's 10 winners, as well as every winner for the previous 25 years.

Cisco Blamed A Router Bug On 'Cosmic Radiation' ( 141

Network World's news editor contacted Slashdot with this report: A Cisco bug report addressing "partial data traffic loss" on the company's ASR 9000 Series routers contended that a "possible trigger is cosmic radiation causing SEU [single-event upset] soft errors." Not everyone is buying: "It IS possible for bits to be flipped in memory by stray background radiation. However it's mostly impossible to detect the reason as to WHERE or WHEN this happens," writes a Redditor identifying himself as a former [technical assistance center] engineer...
"While we can't speak to this particular case," Cisco wrote in a follow-up, "Cisco has conducted extensive research, dating back to 2001, on the effects cosmic radiation can have on our service provider networking hardware, system architectures and software designs. Despite being rare, as electronics operate at faster speeds and the density of silicon chips increases, it becomes more likely that a stray bit of energy could cause problems that affect the performance of a router or switch."

Friday a commenter claiming to be Xander Thuijs, Cisco's principal engineer on the ASR 9000 router, posted below the article, "apologies for the detail provided and the 'concept' of cosmic radiation. This is not the type of explanation I would like to see presented to the respected users of our products. We have made some updates to the DDTS [defect-tracking report] in question with a more substantial data and explanation. The issue is something that we can likely address with an FPD update on the 2x100 or 1x100G Typhoon-based linecard."
United States

US Panel Extends Nuclear Power Tax Credit ( 228

Slashdot reader mdsolar quotes The Hill: The House Ways and Means Committee voted Wednesday to remove a key deadline for a nuclear power plant tax credit... The credit was first enacted in 2005 to spur construction of new nuclear plants, but it has gone completely unused because no new plants have come online since then...

It would likely benefit two reactors under construction at Southern Co.'s Vogtle Electric Generating Plant in Georgia and another two at Virgil C. Summer Nuclear Generating Station in South Carolina. Both projects are at risk of missing the 2020 deadline... "When Congress passed the 2005 act, it could not have contemplated the effort it would take to get a nuclear plant designed and licensed," said representative Tom Rice (R-S.C.).

Although one Democrat criticized the extension by arguing that nuclear power "does better in a socialist economy than in a capitalist one, because nuclear energy prefers to have the public do the cleanup, do the insurance, cover all of the losses and it only wants the profits."

Poor Scientific Research Is Disproportionately Rewarded ( 80

A new study calculates a low probability that real effects are actually being detected in psychology, neuroscience and medicine research paper -- and then explains why. Slashdot reader ananyo writes: The average statistical power of papers culled from 44 reviews published between 1960 and 2011 was about 24%. The authors built an evolutionary computer model to suggest why and show that poor methods that get "results" will inevitably prosper. They also show that replication efforts cannot stop the degradation of the scientific record as long as science continues to reward the volume of a researcher's publications -- rather than their quality.
The article notes that in a 2015 sample of 100 psychological studies, only 36% of the results could actually be reproduced. Yet the researchers conclude that in the Darwin-esque hunt for funding, "top-performing laboratories will always be those who are able to cut corners." And the article's larger argument is until universities stop rewarding bad science, even subsequent attempts to invalidate those bogus results will be "incapable of correcting the situation no matter how rigorously it is pursued."

Our Atmosphere Is Leaking Oxygen and Scientists Don't Know Why ( 163

The Earth's atmosphere has been leaking oxygen and scientists don't know why. Researchers discovered that over the past 800,000 years, atmospheric oxygen levels have dropped by 0.7 percent. How exactly did they discover the leak? By observing ice cores from Greenland and Antarctica, which contain trapped air bubbles representing snapshots of our atmosphere over the past million-odd years. Gizmodo reports: By examining the ratio of oxygen to nitrogen isotopes within these cores, the researchers were able to pull out a trend: oxygen levels have fallen by 0.7 percent over the past 800,000 years, meaning sinks are roughly 2 percent larger than sources. Writing today in Science, the researchers offer a few possible explanations. For one, erosion rates appear to have sped up in recent geologic history, causing more fresh sediment to be exposed and oxidized by the atmosphere, causing more oxygen to be consumed. Long-term climate change could also be responsible. Recent human-induced warming aside, our planet's average temperature had been declining a bit over the past few million years. [Princeton University geologist Daniel Stolper] added that there could be other explanations, too, and figuring out which is correct could prove quite challenging. But learning what controls the knobs in our planet's oxygen cycle is worth the effort. It could help us understand what makes a planet habitable at all -- something scientists are rather keen on, given recent exoplanet discoveries. Stolper's analysis excluded one very unusual part of the record: the last 200 years of industrial human society. "We are consuming O2 at a rate a factor of a thousand times faster than before," Stolper said. "Humankind has completely short-circuited the cycle by burning tons of carbon."

From Bicycles To Washing Machines: Sweden To Give Tax Breaks For Repairs ( 146

jenningsthecat writes: The Swedish government is putting its money where its mouth is when it comes to encouraging the repair of stuff that would otherwise be thrown away, according to both The Guardian and Fast Company. The country's Social Democrat and Green party coalition have submitted proposals to Parliament that would reduce the value-added-tax (VAT) on bicycle, clothing, and shoe repairs from 25% to 12%. Also proposed is an income tax deduction equalling half the labor cost of repairing household appliances. According to The Guardian, "the incentives are part of a shift in government focus from reducing carbon emissions produced domestically to reducing emissions tied to goods produced elsewhere." Per Bolund, Sweden's Minister for Financial Markets and Consumer Affairs, said the policy also tied in with international trends around reduced consumption and crafts, such as the "maker movement" and the sharing economy, both of which have strong followings in Sweden. The VAT cut may create more jobs for immigrants as it could spur the creation of a new home-repairs service industry. Also, from a science standpoint, the incentives could help cut the cost of carbon emissions on the planet as it should in theory reduce emissions linked to consumption. "I believe there is a shift in view in Sweden at the moment. There is an increased knowledge that we need to make our things last longer in order to reduce materials' consumption," Bolund said. The Guardian's report concludes: "The proposals will be presented in parliament as part of the government's budget proposals and if voted through in December will become law from January 1, 2017."

UPS Is Starting To Test Drone Deliveries In the US ( 44

An anonymous reader quotes a report from Quartz: UPS announced Sept. 23 that it has begun testing drone deliveries in the U.S. with drone manufacturer CyPhy Works. The two companies yesterday completed a test of delivering medicine from the coastal town of Beverly, Massachusetts, to Children's Island, a small island about three miles into the Atlantic Ocean. CyPhy's drone has night-vision capabilities, according to a release shared with Quartz. The test yesterday involved a trial situation where an asthmatic child urgently needed an inhaler, which was dispatched from the mainland to the island, arriving far more quickly than it would've taken a boat to get there. CyPhy's drone autonomously flew supplies over the ocean to a group waiting to receive them on the other end, although there was no actual child with asthma in danger. In May, UPS had announced that it was partnering with the drone company Zipline to deliver medical supplies to rural Rwanda, having invested nearly $1 million into the company. UPS has also invested an undisclosed amount in CyPhy. UPS told Quartz that the FAA was aware of its test, and Houston Mills, a commercial pilot with UPS for over a decade and the company's director of airline safety, was recently announced as a member of the FAA's Drone Advisory Committee. The committee is working with industry experts and companies to figure out how to safely integrate a network of commercial drones into U.S. airspace. You can watch the heroic footage of the trial run here.

SpaceX Blast Investigation Suggests Breach in Oxygen Tank's Helium System ( 78

Weeks after a SpaceX rocket exploded inexplicably, engineers at Elon Musk's company have traced the flaw to its source. Space today released the initial results of its investigation, in which it says that a breach in helium system in the Falcon 9's liquid oxygen system caused the sudden flare up. From a Reuters report: SpaceX, owned and operated by technology entrepreneur Elon Musk, was fueling a Falcon 9 rocket on the launch pad in Florida on Sept. 1 in preparation for a routine test-firing when a bright fireball suddenly emerged around the rocket's upper stage. "At this stage of the investigation, preliminary review of the data and debris suggests that a large breach in the cryogenic helium system of the second stage liquid oxygen tank took place," SpaceX said in a statement posted on its website. No one was hurt in the explosion, which could be heard 30 miles (48 km) away from SpaceX's launch pad 40 at Cape Canaveral Air Force Station. The cause of the accident is under investigation.

Computers Decipher Burnt Scroll Found In Ancient Holy Ark ( 231

bsharma writes: Scientists have formally announced their reconstruction of the Ein Gedi Scroll, the most ancient Hebrew scroll since the Dead Sea Scrolls. This was done by CAT scanning the burnt scrolls and virtually reconstructing the layers of scrolls with ink blobs on them. National Geographic reports: "For decades, the Israel Antiquities Authority guarded the document, known as the Ein Gedi Scroll, careful not to open it for fear that the brittle text would shatter to pieces. But last year, scientists announced that they had scanned, virtually unrolled, and translated the scroll's hidden verses -- a feat now formally described in the scientific literature. Based on preliminary scans, [Brent Seales of the University of Kentucky, who specialized in digitally reconstructing damaged texts,] and his colleagues announced in 2015 that the Ein Gedi Scroll was a biblical text from the sixth century A.D. containing a column of text from the book of Leviticus. But the full CT scan results, published on Wednesday in Science Advances, tell a deeper story. Further analysis revealed an extra column of text, ultimately fleshing out the first two chapters of Leviticus -- ironically, a book that begins with God's instructions for burnt offerings. What's more, radiocarbon dating of the scroll suggests that it may be between 1,700 and 1,800 years old, at least 200 years older than previously thought. In fact, the scroll's distinctive handwriting hearkens back to the first or second century A.D., some five centuries earlier than the date ascribed to the scroll last year." University of Cambridge lecturer James Aitken told Smithsonian's Devin Powell in 2015: "There's little of surprise in finding a Leviticus scroll. We probably have many more copies of it than any other book, as its Hebrew style is so simple and repetitive that it was used for children's writing exercises."

Senate Panel Authorizes Money For Mission To Mars ( 134

An anonymous reader quotes a report from USA Today: With a new president on the horizon, a key Senate committee moved Wednesday to protect long-standing priorities of the nation's space program from the potential upheaval of an incoming administration. Members of the Commerce, Science and Transportation Committee passed a bipartisan bill authorizing $19.5 billion to continue work on a Mars mission and efforts to send astronauts on private rockets to the International Space Station from U.S. soil -- regardless of shifting political winds. Under the Senate bill, NASA would have an official goal of sending a crewed mission to Mars within the next 25 years, the first time a trip to the Red Planet would be mandated by law. The legislation would authorize money for different NASA components, including $4.5 billion for exploration, nearly $5 billion for space operations and $5.4 billion for science. Beyond money, the measure would: Direct NASA to continue working on the Space Launch System and Orion multi-purpose vehicle that are the linchpins of a planned mission to send astronauts to Mars by the 2030s. The bill includes specific milestones for an unmanned exploration mission by 2018 and a crewed exploration mission by 2021. Require development of an advanced space suit to protect astronauts on a Mars mission. Continue development of the Commercial Crew Program designed to send astronauts to the space station -- no later than 2018 -- on private rockets launched from U.S. soil. Expand the full use and life of the space station through 2024 while laying the foundation for use through 2028. Allow greater opportunities for aerospace companies to conduct business in Low Earth Orbit. Improve monitoring, diagnosis and treatment of the medical effects astronauts experience from spending time in deep space.

Stephen Hawking Wants To Find Aliens Before They Find Us ( 280

Stephen Hawking is again reminding people that perhaps shouting about our existence to aliens is not the right way to go about it, especially if those aliens are more technologically advanced. In his new half-hour program dubbed, Stephen Hawking's Favorite Places, the theoretical physicist and cosmologist said (via CNET):"If intelligent life has evolved (on Gliese 832c), we should be able to hear it," he says while hovering over the exoplanet in the animated "U.S.S. Hawking." "One day we might receive a signal from a planet like this, but we should be wary of answering back. Meeting an advanced civilization could be like Native Americans encountering Columbus. That didn't turn out so well." Hawking manages to be both worried about exposing our civilization to aliens and excited about finding them. He supports not only Breakthrough: Listen, but also Breakthrough: Starshot, another initiative that aims to send tiny nanocraft to our closest neighboring star system, which was recently found to have an Earth-like planet.

Scientists Discover That Horses Can Use Symbols To Talk To Us ( 167

sciencehabit writes from a report via Science Magazine: Scientists have discovered that horses can learn to use another human tool for communicating: pointing to symbols. They join a short list of other species, including some primates, dolphins, and pigeons, with this talent. Scientists taught 23 riding horses of various breeds to look at a display board with three icons, representing wearing or not wearing a blanket. Horses could choose between a "no change" symbol or symbols for "blanket on" or "blanket off." The horses did not touch the symbols randomly, but made their choices based on the weather. If it was wet, cold, and windy, they touched the blanket-on icon; horses that were already wearing a blanket nosed the "no change" image. But when the weather was sunny, the animals touched the blanket-off symbol; those that weren't blanketed pressed the "no change" icon. The study's strong results show that the horses understood the consequences of their choices, say the scientists, who hope that other researchers will use their method to ask horses more questions. The report has been published in Applied Animal Behaviour Science.

Smoking Permanently Damages Your DNA, Study Finds ( 175

An anonymous reader quotes a report from NBC News: Smoking scars DNA in clear patterns, researchers reported Tuesday. Most of the damage fades over time, they found -- but not all of it. Their study of 16,000 people found that while most of the disease-causing genetic footprints left by smoking fade after five years if people quit, some appear to stay there forever. The marks are made in a process called methylation, which is an alteration of DNA that can inactivate a gene or change how it functions -- often causing cancer and other diseases. The team examined blood samples given by 16,000 people taking part in various studies going back to 1971. In all the studies, people have given blood samples and filled out questionnaires about smoking, diet, lifestyle and their health histories. They found smokers had a pattern of methylation changes affecting more than 7,000 genes, or one-third of known human genes. Many of the genes had known links to heart disease and cancers known to be caused by smoking. Among quitters, most of these changes reverted to the patterns seen in people who never smoked after about five years, the team reported in the American Heart Association journal Circulation: Cardiovascular Genetics. But smoking-related changes in 19 genes, including the TIAM2 gene linked to lymphoma, lasted 30 years, the team found.

Stop Piracy? Legal Alternatives Beat Legal Threats, Research Shows ( 133

An anonymous reader writes: Threatening file-sharers with high fines or even prison sentences is not the best way to stop piracy. New research published by UK researchers shows that perceived risk has no effect on people's file-sharing habits. Instead, the entertainment industries should focus on improving the legal options, so these can compete with file-sharing. Unauthorized file-sharing (UFS) is best predicted by the supposed benefits of piracy. As such, the researchers note that better legal alternatives are the best way to stop piracy. The results are based on a psychological study among hundreds of music and ebook consumers. They were subjected to a set of questions regarding their file-sharing habits, perceived risk, industry trust, and online anonymity. By analyzing the data the researchers found that the perceived benefit of piracy, such as quality, flexibility of use and cost are the real driver of piracy. An increase in legal risk was not directly associated with any statistically significant decrease in self-reported file-sharing.

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