An anonymous reader quotes a report from Ars Technica: In 1935, scientists predicted that the simplest element, hydrogen, could also become metallic under pressure, and they calculated that it would take 25 GigaPascals to force this transition (each Gigapascal is about 10, 000 atmospheres of pressure). That estimate, in the words of the people who have finally made metallic hydrogen, “was way off.” It took until last year for us to reach pressures where the normal form of hydrogen started breaking down into individual atoms — at 380 GigaPascals. Now, a pair of Harvard researchers has upped the pressure quite a bit more, and they have finally made hydrogen into a metal. All of these high-pressure studies rely on what are called diamond anvils. This hardware places small samples between two diamonds, which are hard enough to stand up to extreme pressure. As the diamonds are forced together, the pressure keeps going up. Current calculations suggested that metallic hydrogen might require just a slight boost in pressure from the earlier work, at pressures as low as 400 GigaPascals. But the researchers behind the new work, Ranga Dias and Isaac Silvera, discovered it needed quite a bit more than that. In making that discovery, they also came to a separate realization: normal diamonds weren’t up to the task. “Diamond failure, ” they note, “is the principal limitation for achieving the required pressures to observe SMH, ” where SMH means “solid metallic hydrogen” rather than “shaking my head.” The team came up with some ideas about what might be causing the diamonds to fail and corrected them. One possibility was surface defects, so they etched all diamonds down by five microns to eliminate these. Another problem may be that hydrogen under pressure could be forced into the diamond itself, weakening it. So they cooled the hydrogen to slow diffusion and added material to the anvil that absorbed free hydrogen. Shining lasers through the diamond seemed to trigger failures, so they switched to other sources of light to probe the sample. After loading the sample and cranking up the pressure (literally — they turned a handcrank), they witnessed hydrogen’s breakdown at high pressure, which converted it from a clear sample to a black substance, as had been described previously. But then, somewhere between 465 and 495 GigaPascals, the sample turned reflective, a key feature of metals The study has been published in the journal Science. Read more of this story at Slashdot.
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Scientists Finally Turn Hydrogen Into a Metal, Ending a 80-Year Quest
Reader Mark Wilson writes: Earlier in the year, a huge DDoS attack was launched on Krebs on Security. Analysis showed that the attack pelted servers with 620 Gbps, and there were fears that the release of the Mirai source code used to launch the assault would lead to a rise in large-scale DDoS attacks. Welcome Leet Botnet. In the run-up to Christmas, security firm Imperva managed to fend off a 650 Gbps DDoS attack. But this was nothing to do with Mirai; it is a completely new form of malware, but is described as “just as powerful as the most dangerous one to date”. The concern for 2017 is that “it’s about to get a lot worse”. Clearly proud of the work put into the malware, the creator or creators saw fit to sign it. Analysis of the attack showed that the TCP Options header of the SYN packets used spelled out l33t, hence the Leet Botnet name. Read more of this story at Slashdot.
An anonymous reader quotes a report from Hacked: Earlier this month Hacked reported that a draft version of the much expected EmDrive paper by the NASA Eagleworks team, had been leaked. Now, the final version of the paper has been published. The NASA Eagleworks paper, titled “Measurement of Impulsive Thrust from a Closed Radio-Frequency Cavity in Vacuum, ” has been published online as an open access “article in advance” in the American Institute of Aeronautics and Astronautics (AIAA)’s Journal of Propulsion and Power, a prestigious peer-reviewed journal. The paper will appear in the December print issue of the journal. The final version of the paper is very similar to the leaked draft. In particular, the NASA scientists confirm the promising experimental results: “Thrust data from forward, reverse, and null suggested that the system was consistently performing at 1.2 +/- 0.1 mNkW, which was very close to the average impulsive performance measured in air. A number of error sources were considered and discussed.” The scientists add that, though the test campaign was not focused on optimizing performance and was more an exercise in existence proof, it is still useful to put the observed thrust-to-power figure of 1.2 mN/kW in context. “[For] missions with very large delta-v requirements, having a propellant consumption rate of zero could offset the higher power requirements. The 1.2 mN/kW performance parameter is over two orders of magnitude higher than other forms of ‘zero propellant’ propulsion, such as light sails, laser propulsion, and photon rockets having thrust-to-power levels in the 3.33–6.67 uN/kW (or 0.0033–0.0067 mN/kW) range.” In other words, a modest thrust without having to carry fuel can be better, especially for long-distance space missions, than a higher thrust at the cost of having to carry bulky and heavy propellant reserves, and the EmDrive performs much better than the other “zero propellant” propulsion systems studied to date. Read more of this story at Slashdot.
From Hollister, California — population 40, 000 — comes a good update from the Mercury News on Larry Page’s efforts to fund a flying car: Even from a few hundred yards away, the aircraft made a noise strikingly different from the roar of a typical plane. “It sounded like an electric motor running, just a high-pitched whine, ” said Steve Eggleston, assistant manager at an airplane-parts company with offices bordering the Hollister Municipal Airport tarmac. But it wasn’t only the sound that caught the attention of Eggleston and his co-workers at DK Turbines. It was what the aircraft was doing. “What the heck’s that?” saleswoman Brittany Rodriguez thought to herself. It’s just hovering.” That, apparently, was a flying car, or perhaps a prototype of another sort of aircraft under development by a mysterious startup called Zee.Aero…one of two reportedly funded by Google co-founder Larry Page to develop revolutionary forms of transportation… A Zee.Aero spokeswoman said the firm is “currently not discussing (its) plans publicly.” However, a Zee.Aero patent issued in 2013 describes in some detail an aircraft capable of the hovering seen by people working at the airport. And the drawings showcase a vision of the future in which flying cars park in lots just like their terrestrial, less-evolved cousins. Page has invested $100 million in Zee.Aero, which appears to have hired more than 100 aerospace engineers. But the article reports that apparently, in the small town where it’s headquartered, “the first rule about Zee.Aero is you don’t talk about Zee.Aero.” Read more of this story at Slashdot.