Catch up on stories from the past week (and beyond) at the Slashdot story archive

 


Forgot your password?
Close
typodupeerror
×

Submission + - Netherlands Audio Speakers: Loud Enough to be heard in Space (io9.com) 2

Submitted by retroworks
retroworks writes: Located in Noordwijk, Netherlands, and part of ESA's ESTEDC Test Center, is the Large European Acoustic Facility (LEAF). I09, Gizmodo Australia, and The Mail Online run stories about the awesome power of sound amplification system "powerful enough to kill a human being".

LEAF is capable of generating more than 154 decibels, the sound equivalent to standing next to several jets taking off. It is used to blast satellites and spacecraft with sound. Large horns are housed in a sound-proofed room that is 16.4metres tall. One wall of horns stands 11 m wide by 9 m deep and 16.4 m high. The nitrogen that's shot through the horns can produce a range of noise up to more than 154 decibels.

LEAF requires all the doors to be closed, operating in steel-reinforced concrete walls to contain the noise. The walls are coated with an epoxy resin to reflect noise, producing a uniform sound field within the chamber. The article doesn't say whether the knobs go past 11.

Submission + - Something Hit Earth in 773 AD But Nobody Knows What (medium.com)

Submitted by KentuckyFC
KentuckyFC writes: In November 2012, a group of Japanese scientists discovered that the concentration of carbon-14 in Japanese cedar trees suddenly rose between 774 AD and 775 AD. Others have since found similar evidence and narrowed the date to 773 AD. Astronomers think this stuff must have come from space so now the quest is on to find the extraterrestrial culprit. Carbon-14 is continually generated in the atmosphere by cosmic rays hitting nitrogen atoms. But because carbon-14 is radioactive, it naturally decays back into nitrogen with a half-life of about 5700 years. This constant process of production and decay leaves the amount of carbon-14 in the atmosphere relatively constant at about one part in a trillion will be carbon-14. One possible reason for the increase is that the Sun belched a superflare our way, engulfing the planet in huge cloud of high energy protons. Recent calculations suggest this could happen once every 3000 years and so seems unlikely. Another possibility is a nearby supernova, which bathed the entire Solar System in additional cosmic rays. However, astronomers cannot see any likely candidates nearby and there are no historical observations of a supernova from that time. Yet another possibility is that a comet may have hit the Earth, dumping the extra carbon-14 in the atmosphere. But astronomers have ruled that out on the basis that a comet carrying enough carbon-14 must have been over 100 km in diameter and would surely have left other evidence such as an impact crater. So for the moment, astronomers are stumped.

Comment Re:Using encryption is the better option (Score 1) 128

by __aajfby9338 (#46132315) Attached to: Where Old Hard Disks (with Digital Secrets) Go To Die
A quick search for "miniscribe" on Youtube turned up the Miniscribe 3212 and Miniscribe 3650 as a couple of examples. Unlike my first Miniscribe hard drive (whose model number I don't remember), these ones appear to have optical sensors for track zero mounted on the outside of the stepper motor. Mine simply had a mechanical stop that the drive noisily buzzed against at power-up. But at least it wasn't a brick for the year or two that it lasted before failing.

Comment Re:Using encryption is the better option (Score 1) 128

by __aajfby9338 (#46132169) Attached to: Where Old Hard Disks (with Digital Secrets) Go To Die
My first hard drive was a 20M 3.5" full height SCSI drive made by Miniscribe. It not only had a stepper motor to position the heads; it also simply jammed the heads against a hard stop to find track zero to save the expense of an optical sensor. I don't recall the model number. That piece of junk didn't last too long.

Submission + - Finnish Hacker Isolates GPS Coordinates from Youtube Video Soundtrack (windytan.com)

Submitted by Anonymous Coward
An anonymous reader writes: "The signal sits alone on the left audio channel, so I can completely isolate it. Judging from the spectrogram, the modulation scheme seems to be BFSK, switching the carrier between 1200 and 2200 Hz. I demodulated it by filtering it with a lowpass and highpass sinc in SoX and comparing outputs. Now I had a bitstream at 1200 bps."

Submission + - Riverside, CA considers shutting down free Citywide municipal wi-fi (pe.com)

Submitted by Anonymous Coward
An anonymous reader writes: City staff recommend shutting down the Citywide free wi-fi, citing annual costs of $718,000 for antiquated equipment providing only 512kbps connection speeds, single digit usage by students, and only 4,000 regular users in a City of over 300,000. Can no one provide municipal broadband successfully except Google Fiber?

Submission + - Belgian professor in cryptography hacked - probably by NSA / GCHQ (standaard.be)

Submitted by julf
julf writes: Belgian professor Jean-Jacques Quisquater, internationally renowned expert in data security who has been heavily involved in the electonic payment chips, was the victim of hacking. And, as was the case in the Belgacom hacking affair, there are indications the American secret service NSA and its British counterpart, the GCHQ might be involved.

Comment Re:There is no need to honk. Ever. (Score 1) 267

by __aajfby9338 (#46126215) Attached to: When Cars Go Driverless, What Happens To the Honking?

Very seldom, if someone fell asleep at the traffick light, I give it a very short blip.

Awesome. So you are an asshole. That thing is not there to wake people up, but to avoid accidents.

Right! That's why I never honk to wake up somebody in front of me at a traffic light. I just ram them. It's the polite thing to do!

Submission + - Senator Makes NASA Complete $350 Million Testing Tower That it Will Never Use

Submitted by Hugh Pickens DOT Com
Hugh Pickens DOT Com writes: Phillip Swarts reports in the Washington Times that NASA is completing a $350 million rocket-engine testing tower at Stennis Space Center in Mississippi that NASA doesn’t want it and will never use. “Because the Constellation Program was canceled in 2010 the A-3’s unique testing capabilities will not be needed and the stand will be mothballed upon completion (PDF),” said NASA’s inspector general. The A-3 testing tower will stand 300 feet and be able to withstand 1 million pounds of thrust (PDF). The massive steel structure is designed to test how rocket engines operate at altitudes of up to 100,000 feet by creating a vacuum within the testing chamber to simulate the upper reaches of the atmosphere. Although NASA does not expect to use the tower after construction it is compelled by legislation from Sen. Roger F. Wicker, Mississippi Republican, who says the testing tower will help maintain the research center’s place at the forefront of U.S. space exploration. “Stennis Space Center is the nation’s premier rocket engine testing facility,” says Wicker. “It is a magnet for public and private research investment because of infrastructure projects like the A-3 test stand. In 2010, I authored an amendment to require the completion of that particular project, ensuring the Stennis facility is prepared for ever-changing technologies and demands.” Others disagree calling the project the "Tower of Pork" and noting that the unused structure will cost taxpayers $840,000 a year to maintain. “Current federal spending trends are not sustainable, and if NASA can make a relatively painless contribution to deficit reduction by shutting down an unwanted program, why not let it happen?” says Pete Sepp, executive vice president of the National Taxpayers Union. “It’s not rocket science, at least fiscally.”

Submission + - ARM researching novel chip memory (globalspec.com)

Submitted by Anonymous Coward
An anonymous reader writes: ARM may be best known as processor designer but the company is now working on a non-volatile memory that could scale down to 5nm, according to an Electronics 360 report. The memory is something different called Correlated-electron RAM that was originally developed by a professor at University of Colorado. ARM is joining a research collaboration to try and make the memory an option at ARM-friendly foundries.

Comment Re:If that wasn't crueal and unreasonable... (Score 1) 1038

by __aajfby9338 (#45996059) Attached to: Controversial Execution In Ohio Uses New Lethal Drug Combination

If we were so concerned about humane execution we would use the guillotine.

I'm not sure about that. It's been debated whether a person decapitated by guillotine remains conscious for some period after their head is removed. There seems to be conflicting information about this, but I don't think it's clear that beheading by guillotine renders the victim immediately unconscious.

In contrast, execution by electric chair looks pretty gruesome to spectators, but I think I've read that since the current is passed between the victim's scalp and an ankle, the current flowing through their brain polarizes all of the neurons within milliseconds. Their body may be convulsing and smoking, but is their brain functioning at all while it's happening?

Submission + - Twitter Named in a Racketeering Action for Framing User

Submitted by Evil Esq Bar Asc Law
Evil Esq Bar Asc Law writes: Twitter is named as defendant in a RICO (racketeering) action filed in Colorado Federal Court for having assisted a Silicon Valley law firm to frame a user as having made violent threats. According to the Plaintiff, the law firm left off the true name of the publisher of the Tweet in a complaint they made and Twitter refused to identify the real publisher. Several of the principals of Twitter's venture capital investors are clients of the law firm. This website: [Barra Partners] has the particulars including a motion setting forth some of the details.

Comment Re:Baseballs... (Score 1) 265

Mining is the act of removing very small amounts of valuable minerals from large chunks of rock.

Bringing them HERE means the tailings all end up in earth orbit.

That would only be true if we brought the entire asteroid to earth orbit and then began mining it. If and when it is ever practical to mine asteroids, we would process them in place, bring the valuable stuff to earth surface, and leave the tailings in the same solar orbit they're already in.

Slashdot Top Deals

An authority is a person who can tell you more about something than you really care to know.

Close