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OpenSSH 5.4 Released 127

HipToday writes "As posted on the OpenBSD Journal, OpenSSH 5.4 has been released: 'Some highlights of this release are the disabling of protocol 1 by default, certificate authentication, a new "netcat mode," many changes on the sftp front (both client and server) and a collection of assorted bugfixes. The new release can already be found on a large number of mirrors and of course on'"

7 of the Best Free Linux Calculators 289

An anonymous reader writes "One of the basic utilities supplied with any operating system is a desktop calculator. These are often simple utilities that are perfectly adequate for basic use. They typically include trigonometric functions, logarithms, factorials, parentheses and a memory function. However, the calculators featured in this article are significantly more sophisticated with the ability to process difficult mathematical functions, to plot graphs in 2D and 3D, and much more. Occasionally, the calculator tool provided with an operating system did not engender any confidence. The classic example being the calculator shipped with Windows 3.1 which could not even reliably subtract two numbers. Rest assured, the calculators listed below are of precision quality."
Operating Systems

Ubuntu 10.04 Alpha 2 vs. Early Fedora 13 Benchmarks 157

Given that early benchmarks of the Lucid Lynx were less than encouraging, Phoronix decided to take the latest alpha out for a spin and has set it side-by-side with an early look at Fedora 13. "Overall, there are both positive and negative performance changes for Ubuntu 10.04 LTS Alpha 2 in relation to Ubuntu 9.10. Most of the negative regressions are attributed to the EXT4 file-system losing some of its performance charm. With using a pre-alpha snapshot of Fedora 13 and the benchmark results just being provided for reference purposes, we will hold off on looking into greater detail at this next Red Hat Linux update until it matures."

Simulation of Close Asteroid Fly-By 148

c0mpliant writes "NASA and the Jet Propulsion Laboratory have released a simulation of the path of an asteroid, named Apophis, that will come very close to Earth in 2029 — the closest predicted approach since humans have monitored for such heavenly bodies. The asteroid caused a bit of a scare when astronomers first announced that it would enter Earth's neighborhood some time in the future. However, since that announcement in 2004, more recent calculations have put the odds of collision at 1 in 250,000."

Big Dipper "Star" Actually a Sextuplet System 88

Theosis sends word that an astronomer at the University of Rochester and his colleagues have made the surprise discovery that Alcor, one of the brightest stars in the Big Dipper, is actually two stars; and it is apparently gravitationally bound to the four-star Mizar system, making the whole group a sextuplet. This would make the Mizar-Alcor sextuplet the second-nearest such system known. The discovery is especially surprising because Alcor is one of the most studied stars in the sky. The Mizar-Alcor system has been involved in many "firsts" in the history of astronomy: "Benedetto Castelli, Galileo's protege and collaborator, first observed with a telescope that Mizar was not a single star in 1617, and Galileo observed it a week after hearing about this from Castelli, and noted it in his notebooks... Those two stars, called Mizar A and Mizar B, together with Alcor, in 1857 became the first binary stars ever photographed through a telescope. In 1890, Mizar A was discovered to itself be a binary, being the first binary to be discovered using spectroscopy. In 1908, spectroscopy revealed that Mizar B was also a pair of stars, making the group the first-known quintuple star system."
Open Source

Linux Kernel 2.6.32 Released 195

diegocg writes "Linus Torvalds has officially released the version 2.6.32 of the Linux kernel. New features include virtualization memory de-duplication, a rewrite of the writeback code faster and more scalable, many important Btrfs improvements and speedups, ATI R600/R700 3D and KMS support and other graphic improvements, a CFQ low latency mode, tracing improvements including a 'perf timechart' tool that tries to be a better bootchart, soft limits in the memory controller, support for the S+Core architecture, support for Intel Moorestown and its new firmware interface, run-time power management support, and many other improvements and new drivers. See the full changelog for more details."

Sunspots May Be Different During This Solar Minimum 95

PhreakOfTime writes "According to Bill Livingston and Matt Penn of the National Solar Observatory in Tucson, Arizona, sunspot magnetic fields are waning. The two respected solar astronomers have been measuring solar magnetism since 1992. Their technique is based on Zeeman splitting of infrared spectral lines in radiation emitted by iron atoms in the vicinity of sunspots. Extrapolating their data (PDF) into the future suggests that sunspots could completely disappear within decades." To motivate their interest the researchers mention the Maunder Minimum, which occurred beginning in 1645 and coincided with the coldest part of the so-called "Little Ice Age." Sunspot counts during this period were as low as 1/1,000 of the numbers seen in modern times.

Quantum Setback For Warp Drives 627

KentuckyFC writes "Warp drives were generally considered impossible by mainstream scientists until 1994 when the physicist Michael Alcubierre worked out how to build a faster-than-light drive using the principles of general relativity. His thinking was that while relativity prevents faster-than-light travel relative to the fabric of spacetime, it places no restriction on the speed at which regions of spacetime may move relative to each other. So a small bubble of spacetime containing a spacecraft could travel faster than the speed of light, at least in principle. But one unanswered question was what happens to the bubble when quantum mechanics is taken into account. Now, a team of physicists have worked it out, and it's bad news: the bubble becomes unstable at superluminal speeds, making warp drives impossible (probably)."

Submission + - "Burning" saltwater

RayWalston writes: Shades of cold fusion. A fella, John Kanzius, claims to have found a way using RF to break up saltwater into hydrogen gas. Several demonstrations on youtube, but no real comparison of the amount of RF in vs amount generated. Anyone out there seen anything quantative?

Submission + - Saltwater for fuel

An anonymous reader writes: RIE, Pa. — An Erie cancer researcher has found a way to burn salt water, a novel invention that is being touted by one chemist as the "most remarkable" water science discovery in a century. John Kanzius happened upon the discovery accidentally when he tried to desalinate seawater with a radio-frequency generator he developed to treat cancer. He discovered that as long as the salt water was exposed to the radio frequencies, it would burn. The discovery has scientists excited by the prospect of using salt water, the most abundant resource on earth, as a fuel. Rustum Roy, a Penn State University chemist, has held demonstrations at his State College lab to confirm his own observations. The radio frequencies act to weaken the bonds between the elements that make up salt water, releasing the hydrogen, Roy said. Once ignited, the hydrogen will burn as long as it is exposed to the frequencies, he said. The discovery is "the most remarkable in water science in 100 years," Roy said. "This is the most abundant element in the world. It is everywhere," Roy said. "Seeing it burn gives me the chills." Roy will meet this week with officials from the Department of Energy and the Department of Defense to try to obtain research funding. The scientists want to find out whether the energy output from the burning hydrogen — which reached a heat of more than 3,000 degrees Fahrenheit — would be enough to power a car or other heavy machinery. "We will get our ideas together and check this out and see where it leads," Roy said. "The potential is huge.

Submission + - Saltwater as fuel? (

thevacancy writes: An amateur inventor seems to have stumbled on the ability (new or not) to illicit hydrogen and oxygen from saltwater via radio waves. No information on how much energy is required to produce the radio waves (the contraption looks large), but it looks interesting nonetheless.

Submission + - Saltwater can burn when exposed to radio waves (

realwx writes: "An Erie man who wanted to desalinate water has accidentally discovered saltwater can burn, as long as the saltwater is exposed to radio frequencies. "The radio frequency actually weakens bonds holding together the constituents of salt water — sodium chloride, hydrogen and oxygen — and releases the hydrogen, which, once ignited, burns continuously when exposed to the RF energy field. Mr. Kanzius said an independent source measured the flame's temperature, which exceeds 3,000 degrees Fahrenheit, reflecting an enormous energy output. While Mr. Kanzius was demonstrating how his generator heated nanoparticles, someone noted condensation inside the test tube and suggested he try using his equipment to desalinate water. So, Mr. Kanzius said, he put sea water in a test tube, then trained his machine on it, producing an unexpected spark. In time he and laboratory owners struck a match and ignited the water, which continued burning as long as it remained in the radio-frequency field.""

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