Saturday, February 16, 2013

Cosmological physics in action


video

video

Russia was treated to cosmological physics and a reminder at just how fragile humanity can be.

"Falling Meteor Explodes Over Russia"

Collision With Atmosphere Sends Bright Light and Shock Wave Across Ural Mountains; 1,000 Injured

by

Jamus Marson and Gautam Naik

February 15th, 2013

The Wall Street Journal

A meteor plunged toward earth over Russia's Ural Mountains Friday, exploding into flames in a powerful blast that damaged buildings in nearby areas, injuring around 1,000 people.

Amateur videos broadcast on state television showed an object streaking across the sky, trailing smoke, around 9:20 a.m. local time before bursting into a fireball. It caused a sonic boom from which residents in the city of Chelyabinsk, the largest in the affected region, described a shock wave that blew in doors, smashed glass and set off car alarms.

"The light was so intense that it completely illuminated the courtyard of our apartment block," said Sergei Zakharov, head of the Russian Geographical Society in Chelyabinsk. "The sound, the shock wave came around six minutes later. No one could understand what had happened. I'd compare it to the explosion of a large flare bomb."

Almost 1,000 people sought medical attention, mostly for cuts from flying glass, and 43 were hospitalized, the Emergency Situations Ministry said. Around 3,000 buildings were damaged by the blast, which blew a hole in the walls of a metals factory in Chelyabinsk, approximately 900 miles east of Moscow.

Children were sent home from schools, and the explosion temporarily knocked out one mobile operator's network.


A meteor contrail was seen over Chelyabinsk, Russia, on Friday. The meteor streaked across the sky of Russia's Urals, causing explosions and injuring around 1,000 people.

The unusual sight sowed confusion among some locals. Amateur video showed children in one school streaming out of a classroom and screaming.

"That kind of light doesn't happen in life, only at the end of the world," Vlada Palagina, a Chelyabinsk schoolteacher, told the LifeNews website.

"We thought an airplane had crashed," said a woman who answered the phone at the city administration.

Officials moved quickly to calm residents, saying there was no threat to human life from the rock fragments that hit the earth outside Chelyabinsk. Most of the meteor burned up before pieces hit the ground, scientists said.

President Vladimir Putin ordered the emergency situations minister to provide help for those affected.

A hole in the ice marks a place where a meteorite reportedly crashed into a frozen lake outside the city of Chelyabinsk, Russia, on Friday.

"There's no major destruction," Chelyabinsk regional Governor Mikhail Yuyevich wrote on his blog. "The main task now is to maintain heat in the apartments and offices where the glass was smashed."

Scientists said the incident was a rare event, both in terms of the size of the rock and the number of injuries it caused.

"There have been reports of one or two people being injured in the past. This is entirely unprecedented," said Keith Smith, an astronomer at Britain's Royal Astronomical Society.

Dr. Smith said there was no connection between the meteor event in Russia and the 130,000-ton asteroid that harmlessly passed about 17,000 miles from Earth on Friday. Planetary scientist Samuel Kounaves at Tufts University in Boston also said there likely was no connection.

Asteroids are fairly small pieces of rock that go around the sun. A meteoroid is an even smaller piece of debris or a particle that goes around the sun. A meteor is the light phenomenon we see when a meteoroid burns up as it flies through the atmosphere—what we commonly call shooting stars. A meteorite is a meteoroid that survives its atmosphere plunge and lands on Earth.

In Russia, dozens of fragments of the meteor hit the ground, officials said, and search teams set out looking for meteorites outside Chelyabinsk.

Local police described how one piece smashed into the ground near Lake Chebarkul, throwing up a column of ice, water and steam and creating a 26-foot crater.

The meteor was several yards in diameter and weighed around 10 metric tons, Russia's Academy of Sciences said in a statement. "The object entered the atmosphere at a speed of 15 to 20 kilometers (9 to 12 miles) per second, disintegrated at a height of 30-50 kilometers. The movement of fragments at large speed caused a powerful emission of light and a strong shock wave," the academy said.

According to the U.S. National Aeronautics and Space Administration, meteoroids smaller than 25 meters usually burn up as they streak through the atmosphere, causing little or no damage.

Earth is bombarded with more than 100 tons of dust and sand-sized particles every day, much of it falling into the oceans or remote areas, and otherwise going unnoticed. About once a year, a car-size asteroid enters the atmosphere, though it usually burns up before hitting the surface.

It is only every 2,000 years or so that an object the size of a football field descends to earth and causes significant damage, according to NASA. Giant asteroids that crash to earth—such as the one that most likely extinguished the dinosaurs—tend to occur on the scale of millions of years.

Scientists will likely rush to the site in Russia where the meteor was observed. Astronomer Dr. Smith said there has probably been only one case—in Sudan in 2007—where researchers were able to follow the track of a meteor as it came down and recover pieces of it on the ground.

Russian Deputy Prime Minister Dmitry Rogozin called for leading world powers to create an early-warning system, and consider technology to shoot down meteors. Roskosmos, Russia's space agency, said it was impossible to track objects falling as fast as the meteor.


"A Meteor in the Russian Sky"

by

Elif Batuman

February 15th, 2013

The New Yorker

 At around 9:20 local time on Friday morning, a brilliant fireball, believed to be a meteor, appeared in the sky above the Russian Urals and shot across the horizon, leaving a trail of billowing smoke. A deafening boom shattered windows and television screens throughout the city of Chelyabinsk. Serious damage was reported at a zinc factory and an ice rink. Flying glass caused over five hundred injuries, some requiring hospitalization.

The Russian Academy of Sciences announced that the fireball had been a meteor, that it had weighed ten tons and entered the earth’s atmosphere at some thirty-three thousand miles per hour. It shattered over the Chelyabinsk region, where the Russian Army has reported finding meteorite fragments and a twenty-foot crater. Such events don’t happen every day, but they aren’t totally unheard of. In 1908, the so-called Tunguska Impact levelled eight hundred and thirty square miles of Siberian forestland. The truly new thing about Friday’s meteoric event was, rather, how we got to watch it: from inside people’s cars.

The dashboard-camera videos of the meteor, which proliferated on the Internet all Friday morning, represent an intersection of astronomical forces with the technological and sociohistorical conditions of Russian life. Dash cams, as reported in Animal, have become ubiquitous in today’s Russia, where road hazards range from “insane gridlock” to “large, lawless areas” habited by “police with a penchant for extortion and deeply frustrated drivers who want to smash your face,” and where courts rarely award damages without video evidence. A large percentage of Russian car crashes are thus captured on video and aggregated on a devoted LiveJournal page that gets more than four million views per month. The car-crash video corpus is a gold mine of piquant Russian slang, from the derogatory potsient—a hybrid of “[hospital] patient” and “putz,” used to denote crash victims—to the honorific zhelezobetonnoe ochkko—anus of concrete—for drivers who navigate deadly situations without losing their cool.

Russian dash-cam videos have been around, in other words, but they were a niche taste. The meteor brought them into the mainstream, and shifted the focus: now the collision isn’t between two cars, but between the earth and a celestial rock. The dash-cam videos, capturing the very first glimmer of the unawaited fireball, have a certain dramatic irony: we notice the meteor before the driver does. I found them mesmerizing. I watched them all morning.


At around 9:20 local time on Friday morning, a brilliant fireball, believed to be a meteor, appeared in the sky above the Russian Urals and shot across the horizon, leaving a trail of billowing smoke. A deafening boom shattered windows and television screens throughout the city of Chelyabinsk. Serious damage was reported at a zinc factory and an ice rink. Flying glass caused over five hundred injuries, some requiring hospitalization.

The Russian Academy of Sciences announced that the fireball had been a meteor, that it had weighed ten tons and entered the earth’s atmosphere at some thirty-three thousand miles per hour. It shattered over the Chelyabinsk region, where the Russian Army has reported finding meteorite fragments and a twenty-foot crater. Such events don’t happen every day, but they aren’t totally unheard of. In 1908, the so-called Tunguska Impact levelled eight hundred and thirty square miles of Siberian forestland. The truly new thing about Friday’s meteoric event was, rather, how we got to watch it: from inside people’s cars.

The dashboard-camera videos of the meteor, which proliferated on the Internet all Friday morning, represent an intersection of astronomical forces with the technological and sociohistorical conditions of Russian life. Dash cams, as reported in Animal, have become ubiquitous in today’s Russia, where road hazards range from “insane gridlock” to “large, lawless areas” habited by “police with a penchant for extortion and deeply frustrated drivers who want to smash your face,” and where courts rarely award damages without video evidence. A large percentage of Russian car crashes are thus captured on video and aggregated on a devoted LiveJournal page that gets more than four million views per month. The car-crash video corpus is a gold mine of piquant Russian slang, from the derogatory potsient—a hybrid of “[hospital] patient” and “putz,” used to denote crash victims—to the honorific zhelezobetonnoe ochkko—anus of concrete—for drivers who navigate deadly situations without losing their cool.

Russian dash-cam videos have been around, in other words, but they were a niche taste. The meteor brought them into the mainstream, and shifted the focus: now the collision isn’t between two cars, but between the earth and a celestial rock. The dash-cam videos, capturing the very first glimmer of the unawaited fireball, have a certain dramatic irony: we notice the meteor before the driver does. I found them mesmerizing. I watched them all morning.

In one video, the car comes to a stop at a red light. The turn signal starts its distinctive clacking. The oncoming cars still have their headlights on, and tram lines crisscross the darkened sky. A white, blazing fireball shimmers in the sky, glowing like a Disney shooting star—like something that would precede the materialization of a fairy godmother. As it races toward the horizon, the driver launches into an unhurried stream of Russian profanity, starting with “What the fuck is that?” and getting gradually more colorful. The light changes and, with a few parting profanities, he turns right. The whole scene takes forty-nine seconds. It’s like reading a poem.

 In another video, imprinted with the wrong date and time, a man drives down a country road, listening to dance music, systematically passing one car after another. The fairy godmother comes to visit him, too, but he just keeps driving.

Another driver, heading along a rural highway, listens in phlegmatic silence to an entire pizza commercial as the glowing trail shoots across the sky. He utters only a laconic, anus-of-concrete comment: “What the fuck.”

With their juxtaposition of the cosmic and the mundane, the Russian meteor videos reminded me of Tolstoy’s description, in “War and Peace,” of the comet of 1812:


    Only looking up at the sky did Pierre cease to feel how sordid and humiliating were all mundane things compared with the heights to which his soul had just been raised…. Above the Prechistenka Boulevard, surrounded … on all sides by stars but distinguished from them all by its nearness to the earth, its white light, and its long uplifted tail, shone the enormous and brilliant comet of 1812—the comet which was said to portend all kinds of woes and the end of the world. In Pierre, however, that comet with its long luminous tail aroused no feeling of fear. On the contrary he gazed joyfully, his eyes moist with tears, at this bright comet which, having traveled in its orbit with inconceivable velocity through immeasurable space, seemed suddenly—like an arrow piercing the earth—to remain fixed in a chosen spot, vigorously holding its tail erect, shining and displaying its white light amid countless other scintillating stars. It seemed to Pierre that this comet fully responded to what was passing in his own softened and uplifted soul, now blossoming into a new life.

In “War and Peace” the comet stands for one of the novel’s central themes: the way world-historical forces interact with individual destinies. The ancient, cosmic power of the epic exercises its gravitational pull on the prose of the world. Every time a meteor comes close to the earth, we all think about the end of the world—but our internal soundtrack doesn’t turn off. We’re also thinking about pizza, or passing a slow tractor, or making a turn, and for a magical instant our lives seem to be in conversation with the stars.

 
Sobering...


"There Is No Way to Stop Space Rocks From Hurtling to Earth and Killing You"

by

Spencer Ackerman

February 15th, 2013

Wired

Space is out to kill you. There is no way to stem its aggression. But it’s usually an incompetent killer, so don’t freak out.

The last thing residents of Chelyabinsk, in central Russia, expected on Friday was to see a flaming fireball from the heavens hurtle towards their industrial city. On-scene accounts make it seem like an angry deity enacted His vengeance for some unknown slight. The meteor was actually unrelated to the 2012 DA14 asteroid near Earth, according to NASA. (Which, by the way, you can watch soar by.) But 1,000 Russians were injured from the concussive blast and flying, shattered glass.

All the advanced air defenses that humanity has invested in? The interceptor missile that are (sometimes) able to stop an adversary missile from impacting? The early-warning monitoring systems that are supposed to give humanity enough time to plan a response? They are useless, useless against a meteorite onslaught. Do not believe the stories about the Russians shooting the cosmic rock down.

“The reason, simply put, is physics,”
explains Brian Weeden of the Secure Earth Foundation, a former captain and missile expert in the U.S. Air Force Space Command. Asteroids orbit the sun like Earth does, and occasionally our orbits intersect, causing the rocks to enter the atmosphere as flaming meteors screaming toward impact. They are not flying like airplanes and missiles that air defenses target. Shooting them will not change their speed or trajectory — at best, a missile impact might change its direction somewhat or shatter it into more pieces.

But let’s say that happens. What then? “Now you’ve got a shotgun blast instead of a single shot,” Weeden explains, and “all those pieces are still traveling in the same direction and at the same velocity.” Gulp.

Still, it’s vanishingly unlikely that air defense systems would be able to even make the shot. The Chelyabinsk meteor was traveling at something like 32,000 miles per hour. (A 747?s typical cruising speed? 567 miles per hour.) By the time you notice it, it’s too late to stop it.

Not that you would notice it. Meteors like the one in Chelyabinsk are going to pass through the detection systems that humans have. Telescopes pointed to space are only going to be able to see a ginormous asteroid. Missile warning and air-defense radars run via software that ignores things that aren’t planes and missiles. And the eyes of U.S. military satellites are pointed the wrong way — down toward Earth. The Defense Support Program satellite constellation, for instance, is looking for launches of things like intercontinental ballistic missiles that threaten America, using infrared. But the asteroid is cold until it enters the atmosphere.

And in this case, the asteroid was relatively small, maybe eight to ten tons. The asteroid tracking networks — run by NASA, the European Space Agency and bands of amateurs — are looking for massive space rocks, some the size of moons, and calculating their potential intersection with Earth. That process can provide early warning — years and decades out. Something small enough to slip into the atmosphere like this one is unlikely to be detected. And there’s not a weapon forged by man that could do something about it anyway, short of calling Bruce Willis.

But there’s good news. Space rocks are lousy shots. The Earth is mostly ocean and uninhabited areas. The frequency of meteorite impacts is correlated with size, Weeden explains, and the smaller the meteorites, the more often they land. “But the places where people are is actually pretty small,” he says. Even the injuries that occurred at Chelyabinsk were mostly concussions and accidents from shattered glass, not from the meteorite itself. Close but no cigar, space: “Your odds of dying by a meteor are pretty damn small. You’re thousands of times more likely to die by car on way to work.”

Believe it or not, there is actually a United Nations team convening to spare Earth from the ravages of space. Weeden just met with it in Vienna a few days ago, and its meetings are ongoing. And it has a plan.

Within the United Nations Special Committee on the Peaceful Uses of Outer Space is a subcommittee on science and technology. That subcommittee has an ad hoc advisory team of dozens of space experts from around the world who try to “figure out how to coordinate detections, warnings and response, and possible deflection” of asteroids that might impact Earth, Weeden says. They’re mostly focused on the big asteroids, the ones larger than 100 meters in diameter or bigger. And among their ideas — the one that “physics says should work,” in Weeden’s phrase — is something called a Gravity Tractor.

The idea is to launch a spaceship near a nefarious asteroid. The presence of the spaceship’s inherent gravitational field should impact the asteroid’s, to the point where it might be able to shift the asteroid’s trajectory and get it to avoid the path of Earth’s celestial journey. It’s untested — and apparently it won’t even host astronauts: it’s unmanned, so Bruce Willis can take a knee. But Weeden has faith the Gravity Tractor will work. Here’s a simulation. (It’s worth mentioning that other proposals include Armageddon-style nuclear detonations, laser-beam pushes and even attaching a big-ass cord to pull the thing out of the way.)

Oh, and the name of that United Nations advisory group that came up with the Gravity Tractor? It’s called Action Team 14. “They’re not superheroes,” Weeden helpfully clarifies. But right now, superheroes are the only defense Earth has against falling space rock.


And finally, there always appears to be someone to turn a buck or two after a disaster...




"Stay away from meteorites, government tells Russians"

February 15th, 2013

Wired

Russia's authorities on Friday cautioned residents of the Urals to stay away from any unidentified objects after a meteor dramatically burned up above the region, with a precious meteorite apparently plunging into a local lake.

"Russia's emergency ministry warns all residents of the Urals... not to approach unknown objects," the ministry said on its website, listing several numbers for people to use if they found something unusual.

The meteor spectacularly fell early Friday, causing blasts which blew out windows in the city of Chelyabinsk and left almost a thousand people injured.

Televised reports showed footage from the Chebarkul lake, about 60 kilometres from Chelyabinsk, where a circular hole was discovered in the ice, which regional police said was cut by a meteorite.

Local fishermen saw the falling meteor, which disintegrated into seven pieces. "One of them fell on the shore opposite of the (Chebarkul) town, whipping up a pillar of ice, water and steam," the police said in a statement.

"As a result, a giant circular ice hole eight meters (26 feet) in diameter was formed,"
the report said. Police secured the area and specialists measured radiation, which was normal, it said.

Pictures on the police website showed people standing around looking at the ice hole. One also showed a tiny rock about one centimetre in diameter, laying on ice next to a ruler.

Several such fragments, "hard, black pieces, which look like rock segments," have been recovered, police said.

Classified ad websites quickly had notices put up by enterprising or jestering Russians, offering pieces of the new meteorite for sale. "Two vans of the Chelyabinsk meteorite," said one notice, posted in the "jewelry" section of a Russian website Avito. "Price can be negotiated."

The regional emergency ministry said it had sent people to the Chebarkul area but could not confirm the hole in the ice was caused by an object from space. It also asked people not to panic and keep warm by closing shattered windows with plywood and plastic.

"It's a hole in ice, we have sent a team to inspect it, but I cannot confirm it's from a meteorite," spokesman of the Chelyabinsk branch of the emergency ministry Vyacheslav Ladonkin told AFP.

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