The Action Lab's James Orgill writes, "In this video I show you how it is possible to contain the fire from a burning ball of propane in a wire mesh." Yes, it is possible. But that doesn't mean you should do it. In fact, you shouldn't.
The experiment demonstrates the phenomenon behind the Davy Lamp, a lamp that Sir Humphry Davy invented in 1812 for use in coal mines. From Wikipedia:
The lamp consists of a wick lamp with the flame enclosed inside a mesh screen. The screen acts as a flame arrestor; air (and any firedamp present) can pass through the mesh freely enough to support combustion, but the holes are too fine to allow a flame to propagate through them and ignite any firedamp outside the mesh. It originally burned a heavy vegetable oil.
The lamp also provided a test for the presence of gases. If flammable gas mixtures were present, the flame of the Davy lamp burned higher with a blue tinge. Lamps were equipped with a metal gauge to measure the height of the flame. Miners could place the safety lamp close to the ground to detect gases, such as carbon dioxide, that are denser than air and so could collect in depressions in the mine; if the mine air was oxygen-poor (asphyxiant gas), the lamp flame would be extinguished (black damp or chokedamp). A methane-air flame is extinguished at about 17% oxygen content (which will still support life), so the lamp gave an early indication of an unhealthy atmosphere, allowing the miners to get out before they died of asphyxiation.
Read the rest
By ‘grace of God,’ no one was injured in a massive explosion at the Androscoggin Mill in Jay, Maine, earlier today, reports the Bangor News. Read the rest
The under-construction New Orleans Hard Rock Hotel partially collapsed last week, killing three people and injuring thirty more, and efforts to dislodge cranes attached to the building didn't go entirely to plan on Sunday. CNN reports that the still-stuck second crane is at least now safe to work around, so rescue workers can now explore the debris and recover two bodies known to be within.
Read the rest
On July 16, 1945, US Army detonated the first nuclear weapon in New Mexico's Jornada del Muerto desert. Codenamed Trinity, the test was part of the Manhattan Project. Three weeks later, the United States dropped atomic bombs on Hiroshima and Nagasaki. From the Atom Central page about Trinity:
The bomb was detonated, producing an intense flash and a fireball that expanded to 600 meters in two seconds. The explosive power was equivalent to 18.6 kilotons of TNT. It grew to a height of more than 12 kilometers, boiling up in the shape of a mushroom. Forty seconds later, the blast of air from the bomb reached the observation bunkers, along with a long and deafening roar of sound.
About this footage:
Original Trinity Footage restoration includes removing dirt and scratches and minimizing some defects in the processing of the original negative. Three shots include a wide shot, a medium shot and a close up.
Previously: "Nuclear explosion porn: watch newly declassified 1950s-1960s nuke test films"
Read the rest
No-one was killed in the bus, which was empty of passengers, but the driver suffered serious burns. The explosion was caused by a "traffic accident," say authorities; the vehicle runs on natural gas, the tank is on the roof, and it tried to enter a low tunnel. Read the rest
In Eugene, Oregon yesterday, the Buck Buck Food Cart exploded in a spectacular fireball due to a malfunctioning gas line. Fortunately, nobody was injured. From the Register-Guard:
A battalion chief said three additional buildings suffered damage from the blast, including (the nearby Oakshire Brewing Public House).
Buck Buck owner Mikey Lawrence, who also owns the Black Wolf Supper Club on Willamette Street, said he woke up to a number of calls and texts informing him that the food cart had exploded. Buck Buck sells fried chicken and other southern specialties.
“I live close by so I rode over, waited for the train to pass and then saw it,” Lawrence said at the scene. “And I said, ‘Holy moly.’ Well, it wasn’t as nice as ‘Holy moly,’ but it was quite a shock.”
Read the rest
The Telegraph-Journal is a newspaper in New Brunswick, Canada. It is owned by the Irvings, among Canada's richest industrialists. Yesterday, an oil refinery owned by the Irvings exploded. Here's how the Telegraph-Journal covered it. [via]
Today I learned that yesterday was Thanksgiving in Canada. Read the rest
The animation team from Big Hero 6 did some cool experiments for the "Into the Portal" sequence, and this week they shared one: an exploding 3D pastel fractal. Read the rest
near which the water pipe passed.
(KVN via DIGG)
Read the rest
Weapon physicist Greg Spriggs and his colleagues at Lawrence Livermore National Laboratory have just uploaded dozens of declassified videos to YouTube of nuclear tests from the 1950s and 1960s. From LLNL:
The U.S. conducted 210 atmospheric nuclear tests between 1945 and 1962, with multiple cameras capturing each event at around 2,400 frames per second. But in the decades since, around 10,000 of these films sat idle, scattered across the country in high-security vaults. Not only were they gathering dust, the film material itself was slowly decomposing, bringing the data they contained to the brink of being lost forever....
For the past five years, Lawrence Livermore National Laboratory (LLNL) weapon physicist Greg Spriggs and a crack team of film experts, archivists and software developers have been on a mission to hunt down, scan, reanalyze and declassify these decomposing films. The goals are to preserve the films' content before it's lost forever, and provide better data to the post-testing-era scientists who use computer codes to help certify that the aging U.S. nuclear deterrent remains safe, secure and effective. To date, the team has located around 6,500 of the estimated 10,000 films created during atmospheric testing. Around 4,200 films have been scanned, 400 to 500 have been reanalyzed and around 750 have been declassified.
LLNL Atmospheric Nuclear Tests
Read the rest
From the newly-released archives.
After collecting dust in high-security vaults for more than 65 years, hundreds of reels of film showing Cold War nuclear bomb tests have been declassified by the United States.
From 1945 to 1962, the United States detonated more than 210 nuclear bombs, with multiple cameras capturing each explosion at around 2,400 frames per second.
There's so many to watch! Read the rest
"What happens when you pump 20,000 joules into a watermelon?" rhetorically asks The Backyard Scientist. "Two words. Pink Mist." Read the rest
Cool hedgehogs don't look at explosions
I believe this may be photoshopped, or perhaps clipped from a forthcoming blockbuster reboot of the Sonic the Hedgehog franchise. [via] Read the rest
The Circumstellar Habitable Zone Simulator provides detailed views of six star systems known to have exoplanets. You can change the stars' mass and the planetary distances and fool around with Goldilocks' breakfast, but it's the timeline control that's scary: drag it right to fly through the billions of years, watching the habitable zone head out of town as the star goes nova then contract to nothing. Read the rest
We've posted about this in the past, but it was brought to my attention that the legendary exploding whale news report was rebroadcast not long ago, meaning that the best quality possible (given the age of the 8mm film) is now available for your whale-exploding pleasure.
Read the rest
A SpaceX Falcon 9 rocket and its payload—a communications satellite backed by Facebook—were destroyed this morning during launch tests at Cape Canaveral, Fla. No-one was hurt in the explosion. Read the rest
On a Saturday, a 3.7 magnitude "earthquake" was detected about 168 miles off Florida's Daytona Beach Shores. It now appears that the quake was actually a "shock trial," an explosive test conducted by the US Navy to test the fortitude of the USS Jackson, a new combat ship. From the Daytona Beach News-Journal:
Asked about the reported earthquake on Monday, Dale Eng, a public information officer for the Navy’s Sea Systems Command in Washington, said the Navy is working on a statement it expects to release this week.
Seismographs as far away as Minnesota, Texas and Oklahoma, as well as along the coast of Florida, Georgia and North Carolina, registered the event on Saturday, said Bruce Presgrave, a geophysicist and shift supervisor at the Geological Survey's National Earthquake Information Center in California.
(After being shown the above photo of a shock trial conducted last month) Presgrave said, "That's a smoking gun, isn't it?"
Presgrave planned to contact the Navy to learn more about the charges used in the shock trials as part of the agency's ongoing investigation.
Read the rest
