The town of Macapá is in the north of Brazil, on the coast, where the Amazon River flows into the Atlantic.Read the rest
The finest moments in physics instruction always involves something going bang, blam, or boom, and this is no exception: Purdue's prof Mark French and grad students Craig Zehrung and Jim Stratton built a supersonic ping-pong-ball gun that attains supersonic muzzle velocity:
To demonstrate the conversion of subsonic to supersonic flow, Prof. French and his team designed the gun shown above. The end of the pressure vessel is sealed with laminating tape. Both the nozzle and the barrel are evacuated so the the gas flow is unobstructed. Overall, the gun is a bit less than 12 feet (3.65 m) in length.
To fire the gun, the pressure is increased in the pressure vessel until the tape breaks. French found that two layers of tape ruptured at about 60 psi (414 kPa), and three layers at about 90 psi (620 kPa). The speed of the ball was measured using a high-speed camera viewing the ball moving against a calibrated scale. A typical velocity was a bit over 1,448 km/h (900 mph) – nominally a velocity of Mach 1.23, which is about the top speed of the Soviet-era MIG-19 fighter.
The lead photo should convince the reader that this ping-pong gun is not a toy. The energy and momentum of the ping-pong ball is roughly the same as that of a .32 caliber ACP pistol – not the best choice for defense, to be sure, but quite lethal under the right circumstances.
Ping-pong gun fires balls at supersonic speeds [Gizmag/Brian Dodson]
In Mother Jones, the story behind "Letters to Newtown." This project was instigated by Boardwalk Empire prop-master, freelance illustrator, and Newtown resident Ross MacDonald, and it serves to digitally archive some of the half million cards, letters, and drawings sent to the town of Newtown, CT after the Sandy Hook school shooting.
Jacques Hebert of Mother Jones, the magazine putting this all together with Tumblr, explains, "These messages of love, hope, and sadness have been on display in Newtown Town Hall, and have been viewed by many residents. To broaden access to these cards and preserve them as memories of what Newtown residents and the nation experienced on that tragic day, Mother Jones in partnership with Tumblr is launching the 'Letters to Newtown' project."
"The project will aim to digitally preserve these cards (the town of Newtown can't afford to store them any longer and many will be turned into ash for a future memorial site) by photographing them and uploading them to a special Tumblr for the world to see."
On Sunday, a man walked into a Kroger grocery store in Charlottesville, Virginia with a loaded AR-15 assault rifle on his back. Why? Because he could. From NBC29:
Charlottesville police drew their guns on the man after witnesses reported he brought a gun into the store. They restrained the man to ask him questions, but released him after they confirmed he is not a convicted felon, owned the gun legally and it was not concealed."Kroger Gun Stunt Sparks 2nd Amendment Debate" (Thanks, David Steinberg!)
Police say he was cooperative and did nothing illegal. Officers did find a note in his pocket spelling out his intent to express his 2nd Amendment rights.
Mount Carmel Area Elementary School in Pennsylvania suspended a five-year-old girl for pointing a Hello Kitty bubble-gun at another student, characterizing this as a "terrorist threat." The little girl had to undergo psychiatric evaluation before she was allowed back in. Her parents say that they couldn't get their daughter into another school, because no one wanted a kid with "terrorist" on her transcript. They're considering a lawsuit.
The school claims "the information supplied to the media may not be consistent with the facts" but declines to correct the record. They do, however, offer this empty, mealy-mouthed rubbish: "The Mount Carmel Area School District takes the well-being and safety of students and staff very seriously."
The kindergartner, who attends Mount Carmel Area Elementary School in Pennsylvania, caught administrators’ attention after suggesting she and a classmate should shoot each other with bubbles.
“I think people know how harmless a bubble is. It doesn’t hurt,” said Robin Ficker, an attorney for the girl’s family. According to Ficker, the girl, whose identity has not been released, didn’t even have the bubble gun toy with her at school.
From English Russia, original source unknown, "These are the Chechen homemade guns. There is a risk that the war will never end if they use such weapons..." No way to tell how accurate that description is -- Chechens are such bogeymen in the Russian press-pantheon that I always take anything ascribed to them with a grain of salt.
Here's ex-president George HW Bush's public letter of resignation from the his lifetime membership to NRA, sent after Wayne "Armed guards in schools" LaPierre gave a speech blaming gun laws for the Oklahoma City bombing, implying that the victims were "jack-booted thugs" "wearing Nazi bucket helmets and black storm trooper uniforms."
Al Whicher, who served on my [ United States Secret Service ] detail when I was Vice President and President, was killed in Oklahoma City. He was no Nazi. He was a kind man, a loving parent, a man dedicated to serving his country -- and serve it well he did...
...I am a gun owner and an avid hunter. Over the years I have agreed with most of N.R.A.'s objectives, particularly your educational and training efforts, and your fundamental stance in favor of owning guns.
However, your broadside against Federal agents deeply offends my own sense of decency and honor; and it offends my concept of service to country. It indirectly slanders a wide array of government law enforcement officials, who are out there, day and night, laying their lives on the line for all of us.
This is a thing. It claims to be bulletproof: "The backpack can be quickly brought to the front as a shield or can serve as center of mass protection while fleeing the scene of the shooting." Apparently officially licensed by Disney. $300. There you go.
Katie sez, "'This Modern World' generic gun control cartoon perfectly describes the discussion regarding the Newtown shooting. It was made for the Tucson shooting but, sadly, applies equally to all gun massacres in the USA."
School freaks out because students making a science video with an umbrella were mistaken for school shooters
A school in Pennsylvania went into full-on lockdown when some children who were making a video about the immune system, which involved some sort of play-fighting with an umbrella, were mistaken for gun-toting lunatics. There is a balance between disaster preparedness and "when in trouble, or in doubt, run in circles, scream and shout," and this isn't it. A deputy chief in the video excuses the exercise because the kids were doing something "suspicious," but of course, there's a difference between being secure and being terrified of anything out-of-the-ordinary. Alerting parents and locking down kids when nothing bad is happening isn't making us more secure, it's making us more scared.
Last week, after giving myself an initial overview of the scientific research on how gun ownership and gun laws affect violent crime, I told you that it seems like there's not a solid consensus on this issue. At least not in the United States. Different studies, of different laws, in different places seem to produce a wide variety of results.
On the one hand, this is kind of to be expected with social science. People are hard to pin down. Harder, often, than the Higgs Boson particle. And you can't just do a clean, controlled laboratory study of these issues. Instead, you're left trying to compare specific places, laws, and enforcement techniques that may not be easily comparable, in an attempt to draw a broad conclusion. That's hard.
But, it seems, the National Rifle Association has gone out of its way to make this work even more difficult than it would otherwise be. Since the early 1990s, NRA-backed politicians have attacked firearms research they believe is biased against guns. Alex Seitz-Wald at Salon.com wrote a piece on this back in July, after an earlier mass shooting. He describes how a vaguely worded clause has lead researchers to avoid doing firearms studies at all, for fear of losing their funding.
The Centers for Disease Control funds research into the causes of death in the United States, including firearms — or at least it used to. In 1996, after various studies funded by the agency found that guns can be dangerous, the gun lobby mobilized to punish the agency. First, Republicans tried to eliminate entirely the National Center for Injury Prevention and Control, the bureau responsible for the research. When that failed, Rep. Jay Dickey, a Republican from Arkansas, successfully pushed through an amendment that stripped $2.6 million from the CDC’s budget (the amount it had spent on gun research in the previous year) and outlawed research on gun control with a provision that reads: “None of the funds made available for injury prevention and control at the Centers for Disease Control and Prevention may be used to advocate or promote gun control.”
Dickey’s clause, which remains in effect today, has had a chilling effect on all scientific research into gun safety, as gun rights advocates view “advocacy” as any research that notices that guns are dangerous. Stephen Teret, who co-directs the Johns Hopkins Center for Gun Policy and Research, told Salon: “They sent a message and the message was heard loud and clear. People [at the CDC], then and now, know that if they start going down that road, their budget is going to be vulnerable. And the way public agencies work, they know how this works and they’re not going to stick their necks out.”
In January, the New York Times reported that the CDC goes so far as to “ask researchers it finances to give it a heads-up anytime they are publishing studies that have anything to do with firearms. The agency, in turn, relays this information to the NRA as a courtesy.”
Via Dave Ng
Some useful distinctions, I think:
* Regulating using a gun
* Regulating carrying a gun
* Regulating owning a gun
* Regulating parts of guns
* Regulating tools that can be used to make guns
* Regulating the information necessary to make guns
* Regulating the information necessary to make tools that can be used to make guns
As is usually the case in times of unthinkable horror, The Onion just fucking nails it:
Despairing sources confirmed that the gunman, armed with a semiautomatic assault rifle—a fucking combat rifle, Jesus—walked into a classroom full of goddamned children where his mother was a teacher and, good God, if this is what the world is becoming, then how about we just pack it in and fucking give up, because this is no way to live.
I mean, honestly, all 315 million Americans confirmed.
“Well, I suppose we have to try to pick up the pieces and make some sort of sense of this tragedy and—you know what? Fuck it, I can’t do this,” said Connecticut resident Michael Zaleski, his remarks understandable given the circumstances, because, holy shit, what else can one say? “I’m sorry, but I can’t fucking do this. Can you? Can anyone?”
Roger Ebert's review of the 2003 Van Sant movie "Elephant" contains some of the most coherent criticism of the way the media reports mass killings I've yet read:
Let me tell you a story. The day after Columbine, I was interviewed for the Tom Brokaw news program. The reporter had been assigned a theory and was seeking sound bites to support it. "Wouldn't you say," she asked, "that killings like this are influenced by violent movies?" No, I said, I wouldn't say that. "But what about 'Basketball Diaries'?" she asked. "Doesn't that have a scene of a boy walking into a school with a machine gun?" The obscure 1995 Leonardo Di Caprio movie did indeed have a brief fantasy scene of that nature, I said, but the movie failed at the box office (it grossed only $2.5 million), and it's unlikely the Columbine killers saw it.
The reporter looked disappointed, so I offered her my theory. "Events like this," I said, "if they are influenced by anything, are influenced by news programs like your own. When an unbalanced kid walks into a school and starts shooting, it becomes a major media event. Cable news drops ordinary programming and goes around the clock with it. The story is assigned a logo and a theme song; these two kids were packaged as the Trench Coat Mafia. The message is clear to other disturbed kids around the country: If I shoot up my school, I can be famous. The TV will talk about nothing else but me. Experts will try to figure out what I was thinking. The kids and teachers at school will see they shouldn't have messed with me. I'll go out in a blaze of glory."
In short, I said, events like Columbine are influenced far less by violent movies than by CNN, the NBC Nightly News and all the other news media, who glorify the killers in the guise of "explaining" them. I commended the policy at the Sun-Times, where our editor said the paper would no longer feature school killings on Page 1. The reporter thanked me and turned off the camera. Of course the interview was never used. They found plenty of talking heads to condemn violent movies, and everybody was happy.
Does gun control mean fewer guns on the street and less violence? Does encouraging gun ownership mean better protected people and less violence?
I don't think it's too early to be asking questions like this. When you're faced with a tragedy like what happened today at Sandy Hook Elementary School, it's reasonable to start asking questions about violence prevention. It's part of the bargaining stage of grief — wondering if there's something we could have done that would have prevented all those needless deaths. And let's get one thing straight: Everybody wants to prevent what happened today.
So what can be done about it? And what does the science say?
I've been trying to get a handle on that for the last hour or so and here are three things it seems we can definitively say:
• It would be completely accurate for someone to tell you that studies in places like Australia and Austria found that implementing more stringent gun control laws reduced deaths from gun-related suicides and violent crime.
• It would also be accurate to say that a study of the effects of the Brady Handgun Violence Prevention Act in the United States showed no big reductions in gun-related deaths, except for suicides among people older than 55.
• And it's also true that a 2003 study of conceal-carry laws in Florida found that they seemed to make no difference one way or the other — neither increasing nor reducing rates of violent crime.
Read the rest
The unfortunately named "Sham II" is a homemade Syrian rebel tank whose main gun is directed with an off-brand video-game thumbstick/gamepad controller. Targetting is via webcam and cheap flat-panel display.
The Sham II, an updated version of a previously made Sham I light infantry by Syrian fighters from the al Ansar Brigade, cost approximately $10,000 (not including the gun), according to one rebel fighter whose brother had designed and built it. The vehicle is reportedly covered with steel plating approximately 2.5 centimeters thick. However, the Sham II is admittedly underprepared to defend against rocket-propelled grenades or tank fire. Rebels claimed the Sham II would soon be ushered into a combat role by members of al Ansar's Saad Benmoaz battalion near Aleppo.
Well, that was predictable: days after a 3D printed gun fired a few rounds, Rep Steve Israel has called for a ban on of Wiki Weapons. The congressman points out (correctly) that all-plastic 3D printed weapons would not be easy to spot using traditional methods, such as metal detectors.
However, what Rep Israel doesn't say is how he hopes to accomplish his goal. Firmware locks for 3D printers? A DMCA-like takedown regime for 3D shapefiles that can be used to generate plastic firearms (or parts of plastic firearms?). A mandate on 3D printer manufacturers to somehow magically make it impossible for their products to print out gun-parts?
Every one of those measures is a nonsense and worse: unworkable combinations of authoritarianism, censorship, and wishful thinking. Importantly, none of these would prevent people from manufacturing plastic guns. And all of these measures would grossly interfere with the lawful operation of 3D printers.
The good news is, this world has in it a thing that looks like an elaborate butter-knife, but is really a flintlock pistol. The bad news is, you missed your choice to buy it -- it sold in Sept 2011 for $3750.
This unusual knife/pistol combination has a flintlock pistol as the handle for the knife and the knife the grip area for the pistol. The knife blade is 5 3/4 inch in length with a curved tip (similar to a butter knife) and decorative ricasso with floral scroll engraving. The handle/pistol portion is silver plated with floral scroll engraving. The top has a banner marked "F.X. RICHTER" and the bottom "IN REICHEBERG". The muzzle is coming out of a dragon/serpents mouth. There is a hammer, pan, frizzen and single spring mounted on the right side and the trigger, two springs and a locking mechanism between the hammer and forward spring are mounted on the left side. When the hammer is cocked, the mechanism rotates and the hammer catches a notch and holds the hammer. Pulling the trigger, releases the hammer and the pistol is fired. Due to the fact that the knife is the grip for the pistol, writer assumes there would normally be a scabbard of some sort otherwise firing the pistol could be a little hazardous.
Xact is a digitally targetted rifle: using a heads-up scope, the user tells the rifle what she wants to shoot. The rifle then helps you hit that target, only firing when it's in the crosshairs.
It's aimhack for real life.
CNN reports on the arsenal discovered on the North Korean assassin arrested in Seoul last year: a poison-dart pen, a pen-pistol, a flashlight-gun, and more.
Disguised to look like a Parker ballpoint pen, it contains a poison needle and is practically impossible to identify as a weapon.
The second pen shoots a poison-filled bullet which penetrates the skin and releases the toxin and the third weapon is a flashlight, loaded with up to three bullets. They all look completely innocuous but all three will kill...
... That target was anti-North Korea activist, Park Sang-hak, who has since been given round-the-clock police protection by South Korean authorities. We showed Park the footage of the weapons intended for him. He was shocked.
'Poison' pen mightier than sword for would-be North Korean assassin (Thanks, polymorf!)
Bob Coulston, a woodworker and contractor, has a wildly oversubscribed Kickstarter for a laser-cut plywood "shotgun" rubber-band gun that fires tons of rubber bands at once. There are a couple different kits, and both look like good fun.
The Sheriff shotgun kit is 14 pieces of laser cut plywood stacked and held together with binding bolts (no glue required) to form an awesome one of a kind 10 shot rubber band shotgun kit with three methods of firing.
The 3 modes of shooting:
* "Single Shot" - Pull the trigger to launch a single shot and pump the actuator back to reload the next rubber band
* "Rapid Fire" - Hold the trigger back while pumping the actuator rapidly to launch an arsenal of rubber bands that nothing can escape.
* "Shotgun Blast" - Pump the actuator until all rubber bands are at the top and then pull the trigger to fire a scattered blast of rubber bands that will knock over about anything.