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Chromium

Building All the Major Open-Source Web Browsers 69

Posted by Soulskill
from the who-needs-packages dept.
An anonymous reader writes: Cristophe de Dinechin, long-time software developer, has an interesting article on the processes involved in building the major browsers. From the article:

"Mozilla Firefox, Chromium (the open-source variant of Chrome) and WebKit (the basis for Safari) are all great examples of open-source software. The Qt project has a simple webkit-based web browser in their examples. So that's at least four different open-source web browsers to choose from. But what does it take to actually build them? The TL;DR answer is that these are complex pieces of software, each of them with rather idiosyncratic build systems, and that you should consider 100GB of disk space to build all the browsers, a few hours of download, and be prepared to learn lots of new, rather specific tools."
Science

Decades-old Scientific Paper May Hold Clues To Dark Matter 92

Posted by Soulskill
from the how-scientists-become-hoarders dept.
sciencehabit writes: Here's one reason libraries hang on to old science journals: A paper from an experiment conducted 32 years ago may shed light on the nature of dark matter, the mysterious stuff whose gravity appears to keep the galaxies from flying apart. The old data put a crimp in the newfangled concept of a 'dark photon' and suggest that a simple bargain-basement experiment could put the idea to the test. The data come from E137, a "beam dump" experiment that ran from 1980 to 1982 at SLAC National Accelerator Laboratory in Menlo Park, California. In the experiment, physicists slammed a beam of high-energy electrons, left over from other experiments, into an aluminum target to see what would come out. Researchers placed a detector 383 meters behind the target, on the other side of a sandstone hill 179 meters thick that blocked any ordinary particles.
China

Mark Zuckerberg Speaks Mandarin At Tsinghua University In Beijing 213

Posted by samzenpus
from the use-your-words dept.
HughPickens.com writes Abby Phillip reports at the Washington Post that that Mark Zuckerberg just posted a 30-minute Q&A at Tsinghua University in Beijing in which he answered every question exclusively in Chinese — a notoriously difficult language to learn and particularly, to speak. "It isn't just Zuckerberg's linguistic acrobatics that make this a notable moment," writes Philip. "This small gesture — although some would argue that it is a huge moment — is perhaps his strongest foray into the battle for hearts and minds in China." Zuckerberg and Facebook have been aggressively courting Chinese users for years and the potential financial upside for the business. Although Beijing has mostly banned Facebook, the company signed a contract for its first ever office in China earlier this year. A Westerner speaking Mandarin in China — at any level — tends to elicit joy from average Chinese, who seem to appreciate the effort and respect they feel learning Mandarin demonstrates. So how well did he actually do? One Mandarin speaker rates Zuckerberg's language skills at a seventh grader's speech: "It's hard not see a patronizing note in the Chinese audience's reaction to Zuckerberg's Mandarin. To borrow from Samuel Johnson's quip, he was like a dog walking on its hind legs: It wasn't done well, but it was a surprise to see it done at all."
Data Storage

Ask Slashdot: Smarter Disk Space Monitoring In the Age of Cheap Storage? 170

Posted by timothy
from the percentages-matter-too-though dept.
relliker writes In the olden days, when monitoring a file system of a few 100 MB, we would be alerted when it topped 90% or more, with 95% a lot of times considered quite critical. Today, however, with a lot of file systems in the Terabyte range, a 90-95% full file system can still have a considerable amount of free space but we still mostly get bugged by the same alerts as in the days of yore when there really isn't a cause for immediate concern. Apart from increasing thresholds and/or starting to monitor actual free space left instead of a percentage, should it be time for monitoring systems to become a bit more intelligent by taking space usage trends and heuristics into account too and only warn about critical usage when projected thresholds are exceeded? I'd like my system to warn me with something like, 'Hey!, you'll be running out of space in a couple of months if you go on like this!' Or is this already the norm and I'm still living in a digital cave? What do you use, on what operating system?
Space

Two Exocomet Families Found Around Baby Star System 23

Posted by samzenpus
from the across-the-universe dept.
astroengine writes Scientists have found two families of comets in the developing Beta Pictoris star system, located about 64 light-years from Earth, including one group that appears to be remnants of a smashed-up protoplanet. The discovery bolsters our theoretical understanding of the violent processes that led to the formation of Earth and the other terrestrial planets in the solar system. "If you look back at the solar system when it was only 22 million years old, you might have seen phenomena that's a like more like what's happening in Beta Pic," astrophysicist Aki Roberge, with NASA Goddard Space Flight Center, Greenbelt, Md., told Discovery News.
Space

Astronomers Find Brightest Pulsar Ever Observed 68

Posted by Soulskill
from the go-big-or-go-home dept.
An anonymous reader writes: Astronomers using the Chandra X-ray Observatory and the NuSTAR satellite have discovered a pulsar so bright that it challenges how scientists think pulsars work. While observing galaxy M82 in hopes of spotting supernovae, the researchers found an unexpected source of X-rays very close to the galaxy's core. It was near another source, thought to be a black hole. But the new one was pulsing, which black holes don't do. The trouble is that according to known pulsar models, it's about 100 times brighter than the calculated limits to its luminosity (abstract). Researchers used a different method to figure out its mass, and the gap shrank, but it's still too bright to fit their theories.
Space

What It Took For SpaceX To Become a Serious Space Company 95

Posted by Soulskill
from the gumption-and-elbow-grease-(and-piles-of-cash) dept.
An anonymous reader writes: The Atlantic has a nice profile of SpaceX's rise to prominence — how a private startup managed to successfully compete with industry giants like Boeing in just a decade of existence. "Regardless of its inspirations, the company was forced to adopt a prosaic initial goal: Make a rocket at least 10 times cheaper than is possible today. Until it can do that, neither flowers nor people can go to Mars with any economy. With rocket technology, Musk has said, "you're really left with one key parameter against which technology improvements must be judged, and that's cost." SpaceX currently charges $61.2 million per launch. Its cost-per-kilogram of cargo to low-earth orbit, $4,653, is far less than the $14,000 to $39,000 offered by its chief American competitor, the United Launch Alliance. Other providers often charge $250 to $400 million per launch; NASA pays Russia $70 million per astronaut to hitch a ride on its three-person Soyuz spacecraft. SpaceX's costs are still nowhere near low enough to change the economics of space as Musk and his investors envision, but they have a plan to do so (of which more later)."
Space

First Evidence of Extrasolar Planets Discovered In 1917 58

Posted by Soulskill
from the but-who's-counting dept.
KentuckyFC writes: Earth's closest white dwarf is called van Maanen 2 and sits 14 light-years from here. It was discovered by the Dutch astronomer Adriaan van Maanen in 1917, but it was initially hard to classify. That's because its spectra contains lots of heavy elements alongside hydrogen and helium, the usual components of a white dwarf photosphere. In recent years, astronomers have discovered many white dwarfs with similar spectra and shown that the heavy elements come from asteroids raining down onto the surface of the stars. It turns out that all these white dwarfs are orbited by a large planet and an asteroid belt. As the planet orbits, it perturbs the rocky belt, causing asteroids to collide and spiral in toward their parent star. This process is so common that astronomers now use the heavy element spectra as a marker for the presence of extrasolar planets. A re-analysis of van Maanen's work shows that, in hindsight, he was the first to discover the tell-tale signature of extrasolar planets almost a century ago.
Space

Mars Orbiter Beams Back Images of Comet's Surprisingly Tiny Nucleus 47

Posted by timothy
from the knowledge-through-correction dept.
astroengine writes The High-Resolution Imaging Science Experiment (HiRISE) camera on board NASA's Mars Reconnaissance Orbiter (MRO) has become the first instrument orbiting Mars to beam back images of comet Siding Spring's nucleus and coma. And by default, it has also become the first ever mission to photograph a long-period comet's pristine nucleus on its first foray into the inner solar system. Interestingly, through analysis of these first HiRISE observations, astronomers have determined that the icy nucleus at the comet's core is much smaller than originally thought. "Telescopic observers had modeled the size of the nucleus as about half a mile, or one kilometer, wide," writes a NASA Jet Propulsion Laboratory news release. "However, the best HiRISE images show only two to three pixels across the brightest feature, probably the nucleus, suggesting a size less than half that estimate."
NASA

A Look At Orion's Launch Abort System 44

Posted by Soulskill
from the for-really-bad-days dept.
An anonymous reader writes: With the construction of Orion, NASA's new manned spacecraft, comes the creation of a new Launch Abort System — the part of the vehicle that will get future astronauts back to Earth safely if there's a problem at launch. The Planetary Society's Jason Davis describes it: "When Orion reaches the apex of its abort flight, it is allowed to make its 180-degree flip. The capsule of astronauts, who have already realized they will not go to space today, experience a brief moment of weightlessness before the capsule starts falling back to Earth, heat shield down. The jettison motor fires, pulling the LAS away from Orion. ... Orion, meanwhile, sheds its Forward Bay Cover, a ring at the top of the capsule protecting the parachutes. Two drogue chutes deploy, stabilizing the wobbling capsule. The drogues pull out Orion's three main chutes, no doubt eliciting a sigh of relief from the spacecraft's occupants."
Mars

NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew 396

Posted by timothy
from the couple-of-jockeys-too dept.
globaljustin writes "Alan Drysdale, a systems analyst in advanced life support and a contractor with NASA concluded, "Small women haven't been demonstrated to be appreciably dumber than big women or big men, so there's no reason to choose larger people for a flight crew when it's brain power you want," says Drysdale. "The logical thing to do is to fly small women." Kate Greene, who wrote the linked article, took part in the first HI-SEAS experiment in Martian-style living, and has some compelling reasons for an all-women crew, energy efficiency chief among them: Week in and week out, the three female crew members expended less than half the calories of the three male crew members. Less than half! We were all exercising roughly the same amount—at least 45 minutes a day for five consecutive days a week—but our metabolic furnaces were calibrated in radically different ways. During one week, the most metabolically active male burned an average of 3,450 calories per day, while the least metabolically active female expended 1,475 calories per day. It was rare for a woman on crew to burn 2,000 calories in a day and common for male crew members to exceed 3,000. ... The calorie requirements of an astronaut matter significantly when planning a mission. The more food a person needs to maintain her weight on a long space journey, the more food should launch with her. The more food launched, the heavier the payload. The heavier the payload, the more fuel required to blast it into orbit and beyond. The more fuel required, the heavier the rocket becomes, which it in turn requires more fuel to launch.
Transportation

The Largest Ship In the World Is Being Built In Korea 274

Posted by timothy
from the and-vice-versa dept.
HughPickens.com writes Alastair Philip Wiper writes that at 194 feet wide and 1,312 feet long, the Matz Maersk Triple E is the largest ship ever built, capable of carrying 18,000 20-foot containers. Its propellers weigh 70 tons apiece and it is too big for the Panama Canal, though it can shimmy through the Suez. A U-shaped hull design allows more room below deck, providing capacity for 18,000 shipping containers arranged in 23 rows – enough space to transport 864 million bananas. The Triple-E is constructed from 425 pre-fabricated segments, making up 21 giant "megablock" cross sections. Most of the 955,250 liters of paint used on each ship is in the form of an anti- corrosive epoxy, pre-applied to each block. Finally, a polyurethane topcoat of the proprietary Maersk brand color "Hardtop AS-Blue 504" is sprayed on.

Twenty Triple-E class container ships have been commissioned by Danish shipping company Maersk Lines for delivery by 2015. The ships are being built at the Daewoo Shipbuilding and Marine Engineering factory in the South Korean port of Opko. The shipyard, about an hour from Busan in the south of the country, employs about 46,000 people, and "could reasonably be described as the worlds biggest Legoland," writes Wiper. "Smiling workers cycle around the huge shipyard as massive, abstractly over proportioned chunks of ships are craned around and set into place." The Triple E is just one small part of the output of the shipyard, as around 100 other vessels including oil rigs are in various stages of completion at the any time." The vessels will serve ports along the northern-Europe-to-Asia route, many of which have had to expand to cope with the ships' size. "You don't feel like you're inside a boat, it's more like a cathedral," Wiper says. "Imagine this space being full of consumer goods, and think about how many there are on just one ship. Then think about how many are sailing round the world every day. It's like trying to think about infinity."
Space

The Woman Who Should Have Been the First Female Astronaut 200

Posted by timothy
from the actually-my-grandmother-would-have-been-great-at-it-too dept.
StartsWithABang writes We like to think of the Mercury 7 — the very first group of NASA astronauts — as the "best of the best," having been chosen from a pool of over 500 of the top military test pilots after three rounds of intense physical and mental tests. Yet when women were allowed to take the same tests, one of them clearly distinguished herself, outperforming practically all of the men. If NASA had really believed in merit, Jerrie Cobb would have been the first female in space, even before Valentina Tereshkova, more than 50 years ago. She still deserves to go.
NASA

NASA Cancels "Sunjammer" Solar Sail Demonstration Mission 74

Posted by timothy
from the only-tax-dollars dept.
An anonymous reader writes "Space News reports that NASA has cancelled its solar sail demonstration mission (also known as Sunjammer) citing "a lack of confidence in its contractor's ability to deliver." "Company president Nathan] Barnes said that in 2011 he reached out to several NASA centers and companies that he believed could build the spacecraft and leave L'Garde free to focus on the solar sail. None of those he approached — he only identified NASA's Jet Propulsion Laboratory in Pasadena, California — took him up on the offer. Rather than give up on the opportunity to land a NASA contract, L'Garde decided to bring the spacecraft development in house. It did not work out, and as of Oct. 17, the company had taken delivery of about $2 million worth of spacecraft hardware including a hydrazine tank from ATK Space Systems of Commerce, California, and four mono-propellant thrusters from Aerojet Rocketdyne of Sacramento, California."
Space

Watch Comet Siding Spring's Mars Fly-By, Live 33

Posted by timothy
from the buzzing-the-tower dept.
From the L.A. Times, and with enough time to tune in, comes this tip: Comet Siding Spring's closest approach to the red planet will occur at 11:27 a.m. [Pacific Time] on Sunday. At its closest approach, the comet will come within 87,000 miles of Mars. That's 10 times closer than any comet on record has ever come to Earth. Sadly, this historic flyby is not visible to the naked eye. People who live in the Southern Hemisphere have a shot at seeing the comet if they have access to a good telescope six inches or wider. However, most of us in the Northern Hemisphere will not be able to see the comet at all, experts say, no matter how big a telescope we've got. Here to save the cometary day is astronomy website Slooh.com. Beginning at 11:15 a.m PDT on Sunday, it will host a live broadcast of the comet's closest approach to Mars, as seen by the website's telescopes in South Africa and in the Canary Islands. Later in the day, beginning at 5:30 p.m. PDT, Slooh will broadcast another view of the comet from a telescope in Chile.
GUI

Apple Doesn't Design For Yesterday 369

Posted by timothy
from the new-one-looks-nice-to-me dept.
HughPickens.com writes Erik Karjaluoto writes that he recently installed OS X Yosemite and his initial reaction was "This got hit by the ugly stick." But Karjaluoto says that Apple's decision to make a wholesale shift from Lucida to Helvetica defies his expectations and wondered why Apple would make a change that impedes legibility, requires more screen space, and makes the GUI appear fuzzy? The Answer: Tomorrow.

Microsoft's approach with Windows, and backward compatibility in general, is commendable. "Users can install new versions of this OS on old machines, sometimes built on a mishmash of components, and still have it work well. This is a remarkable feat of engineering. It also comes with limitations — as it forces Microsoft to operate in the past." But Apple doesn't share this focus on interoperability or legacy. "They restrict hardware options, so they can build around a smaller number of specs. Old hardware is often left behind (turn on a first-generation iPad, and witness the sluggishness). Meanwhile, dying conventions are proactively euthanized," says Karjaluoto. "When Macs no longer shipped with floppy drives, many felt baffled. This same experience occurred when a disk (CD/DVD) reader no longer came standard." In spite of the grumblings of many, Karjaluoto doesn't recall many such changes that we didn't later look upon as the right choice.
The Military

India Successfully Launches Region-Specific Navigation Satellite 86

Posted by timothy
from the gps-for-certain-values-of-g dept.
vasanth writes India has successfully launched IRNSS-1C, the third satellite in the Indian Regional Navigation Satellite System (IRNSS), early on October 16. This is the 27th consecutively successful mission of the PSLV(Polar Satellite Launch Vehicle). The entire constellation of seven satellites is planned to be completed by 2015. The satellite is designed to provide accurate position information service to users in the country as well as in the region extending up to 1,500 km from its boundary, which is its primary service area. In the Kargil war in 1999, the Indian military sought GPS data for the region from the U.S. The space-based navigation system maintained by the U.S. government would have provided vital information, but the U.S. denied it to India. A need for an indigenous satellite navigation system was felt earlier, but the Kargil experience made India realise its inevitability in building its own navigation system. "Geopolitical needs teach you that some countries can deny you the service in times of conflict. It's also a way of arm twisting and a country should protect itself against that," said S Ramakrishnan, director of Vikram Sarabhai Space Centre, Thiruvananthapuram.
Data Storage

Making Best Use of Data Center Space: Density Vs. Isolation 56

Posted by samzenpus
from the best-of-both-worlds dept.
jfruh writes The ability to cram multiple virtual servers on a single physical computer is tempting — so tempting that many shops overlook the downsides of having so many important systems subject to a single point of physical failure. But how can you isolate your servers physically but still take up less room? Matthew Mobrea takes a look at the options, including new server platforms that offer what he calls "dense isolation."
United States

White House Wants Ideas For "Bootstrapping a Solar System Civilization" 351

Posted by samzenpus
from the to-the-stars dept.
MarkWhittington writes Tom Kalil, the Deputy Director for Policy for the White House Office of Science and Technology Policy and Senior Advisor for Science, Technology and Innovation for the National Economic Council, has an intriguing Tuesday post on the OSTP blog. Kalil is soliciting ideas for "bootstrapping a solar system civilization." Anyone interested in offering ideas along those lines to the Obama administration can contact a special email address that has been set up for that purpose. The ideas that Kalil muses about in his post are not new for people who have studied the question of how to settle space at length. The ideas consist of sending autonomous robots to various locations in space to create infrastructure using local resources with advanced manufacturing technology, such as 3D printing. The new aspect is that someone in the White House is publicly discussing these concepts.
Space

Saturn's 'Death Star' Moon May Hide Subsurface Ocean 48

Posted by samzenpus
from the that's-no-ocean dept.
astroengine writes With its heavily cratered, geologically dead surface, Saturn's moon Mimas was considered to be scientifically boring. But appearances can be deceiving. Using data from NASA's Cassini spacecraft, new research shows something strange inside Mimas that is causing the moon to sway as it orbits around the ringed gas giant. Computer models point to two possibilities. First is that Mimas, which is about 250 miles in diameter, has an oblong or football-shaped core, a clue that the moon may have formed inside Saturn's ice rings. The second option is that Mimas has a global ocean located 16 miles to 19 miles beneath its icy crust.

Take care of the luxuries and the necessities will take care of themselves. -- Lazarus Long

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