Tuesday, February 19, 2013

The shock wave from the meteor that exploded above Siberia last week somehow sheared the roof off a brick and steel factory building while leaving a nearby glass facade unscathed. In some high-rises in this city, every window blew out on the top floor; elsewhere, the windows on the ground floors suffered.
More ominously, reports came in to local news media over the weekend of stranger phenomena: behind unshattered apartment windows, glass jugs were said to explode into shards, dishes to crack, electronics to die. Balconies rattled. One man said a bottle broke right in his hand. One woman saw the flash, then heard explosions, then found the windows of her enclosed balcony blown in; her neighbor, with identical windows, escaped without property damage.
There seemed to be randomness in whose property was damaged. Scientists believe the space rock that tore through the atmosphere on Friday morning and blew apart here was the largest to have entered the atmosphere since 1908 and that it was UNUSUAL as well FOR THE SCALE OF ITS EFFECTS: more than 1,200 people injured and broad property damage. Indeed, the event is providing a first indication of the type of structural and infrastructural costs meteors can exact from a highly industrialized society. NASA scientists say a meteor of this size strikes the Earth about once every hundred years.
Shattered glass caused most of the damage and injuries here in Chelyabinsk, a sprawling industrial city of about a million people. What shattered the glass, scientists say, was both the explosion as the meteor fragmented and the waves of pressure created as it decelerated. Such low-frequency waves — called infrasound — are sometimes detected by cold-war era nuclear blast sensors in remote parts of the Pacific Ocean or Alaska.
. The waves can bounce off buildings and be stronger in some places than others; they can also resonate with glass, explaining why bottles and dishes might have shattered inside undamaged kitchens, as if crushed by the airy hand of the meteor itself. “A shock wave is like a ball. Throw a ball into a room and it will bounce from one wall to another.”
Russia has mobilized 24,000 emergency officials to inspect roads, railroads, hospitals, factories and military facilities. Most are undamaged, including 122 sites identified as particularly critical, including nuclear power plants, dams and chemical factories, and a space launching site called Strela. Also Sunday, Russia’s consumer safety inspection agency, Rospotrebnadzor, released a statement saying the water in Lake Chebarkul, where a hole in the ice appeared on Friday, was not radioactive.
It was unclear why the agency released this finding only Sunday, or whether the tests were conducted to assuage popular concerns or out of any real official uncertainty over what happened on Friday. In any case, the agency said a mobile laboratory quietly dispatched to the lake tested for but did not discover cesium 137 and strontium 90, isotopes created in nuclear explosions. Infrasound waves have not previously been studied in a cityscape. But the apparent randomness of the damage was consistent with the way such waves function.
“A shock wave can be coming from a particular direction, and if you face that direction you are more susceptible. One building might shadow another, or you may have a street that is optimally aligned to channel the wave, either in a fortunate or unfortunate way.” An infrasound wave “is very efficient at traveling long distances,” and “windows, structures or even glass jars susceptible to resonate at this frequency could be a factor to seemingly random damage at widely disparate locations.”
A similar, though smaller, explosion of a meteor over the Pacific Ocean occurred on Oct. 8, 2009, which also sent out low-frequency waves, though too remote to affect homes or industry. They were, though, registered by a network of infrasound sensors established to monitor compliance with the international ban on nuclear tests. The spokesman for the governor of Chelyabinsk region characterized the damage there as without a discernible pattern. “It is impossible to say more glass broke in one part of the city or another. Glass broke everywhere.”
The roof of the zinc factory that collapsed was reinforced with a lattice of steel beams and supported by concrete joists that are now broken, jutting upward with mangled re-bar protruding. Windows on a neighboring house blew in with such force that the frames went with them. Yet a few yards away on Sverdlovsky Street, the cosmos spared a seemingly vulnerable Hundai dealership, a three-story cube sheathed in glass, with glistening display models inside. Not a window broke.

**Art and revolt will die only with the last man.**
Albert Camus


LARGEST QUAKES -
Live Seismograms - Worldwide (update every 30 minutes)

This morning -
None 5.0 or larger.

Yesterday -
2/18/13 -
5.6 KERMADEC ISLANDS, NEW ZEALAND
5.9 KERMADEC ISLANDS, NEW ZEALAND
5.2 SANTA CRUZ ISLANDS
5.4 OFFSHORE O'HIGGINS, CHILE
5.6 CENTRAL MID-ATLANTIC RIDGE

VOLCANOES -
Volcano Webcams

Russia warns about volcano eruption - The Geophysical Service of the Russian Academy of Sciences has issued an advisory to airlines, urging them to avoid flying over the Kamchatka mountains where four volcanoes have become more active. hese include Shiveluch, Karymsky, Kizimen, and Flat Tolbachik.
The ash from these volcanoes can cause fatal consequences. If the particles get caught in aircraft engines, a crash would be inevitable. At the moment Shiveluch volcano is throwing a column of ash to a height almost 4,500 meters above sea level, while Karymsky volcano is spewing ash at a height of about 2,700 meters above sea level. RAS assured that the volcanic activity for the local population was not serious.
The Kamchatka peninsula is a 1,250-kilometer peninsula in the Russian Far East. It lies between the Pacific Ocean to the east and the Sea of Okhotsk to the west. Immediately offshore along the Pacific coast of the peninsula runs the 10,500-meter deep Kuril-Kamchatka Trench.
Kamchatka volcano lava stops near research site - A lava flow from the erupting Plosky Tolbachik volcano in Russia's Far Eastern Kamchatka Peninsula has stopped less than three km away from a research site, the Kamchatka Volcano Observatory said on Monday.
"The lava flow that was approaching the Tolud research site has ceased its movement. It didn’t reach the base due to ground profile." During the eruption, which began on November 27, two fissures formed on the southern slope of the volcano. Lava from the upper fissure covered more than six km, while the flow effusing from the lower fissure covered more than 20 km.
A scientist based at the Tolud volcanologists' research site next to the volcano said last Wednesday that the lava flow was threatening the camp, but the Emergencies Ministry dismissed the report the following day. The Plosky Tolbachik volcano, located 343 kilometers (217 miles) from the region's capital of Petropavlovsk-Kamchatsky, began erupting on November 27 for the first time in 36 years. Kamchatka is one of the most volcanically-active areas in the world with 29 active volcanos.

TROPICAL STORMS -
In the Western Pacific -
Tropical Depression Two was located approximately 275 nm east-southeast of Zamboanga, Philippines.

In the South Indian Ocean -
Tropical Cyclone Sixteen was located approximately 335 nm west of Antananarivo, Madagascar - expected to track over southern Madagascar.

SPACE WEATHER -

Possible meteor shower sighting in South Florida - Some South Floridians reported seeing bright, flare-like objects disappear into the sky Sunday night, in what resembled a meteor shower.
The Coast Guard's command center starting receiving reports of a possible meteor shower at about 7:30 p.m. The Coast Guard could neither confirm nor deny whether it was, in fact, a meteor shower. The Coast Guard sent out a helicopter to check on a report of a flare but found nothing. There were no injuries and no boats in distress after the reported sightings. The Broward Sheriff's Office also reported receiving several calls from locals claiming there were "lights in the sky."

Meteorite could have devastated northern United Kingdom - Slight difference in time at which meteorite entered atmosphere could have resulted in widespread damage, say astronomers.
The region around Chelyabinsk hit by the meteorite impact is 55 degrees north, the same latitude as northern England. Had the meteorite's timing been only few hours different, it could have caused widespread damage in the British Isles, astronomers said. If a larger object, such as asteroid 2012 DA14 which grazed Earth later that day, had hit the planet, it would have obliterated any city it struck, they added.
These events have led several teams of scientists to propose schemes aimed at pinpointing asteroids or meteorites that could strike Earth and devastate regions. One is to be built by Hawaii University and is known as Atlas: Asteroid Terrestrial-Impact Last Alert System. It will consist of a series of eight telescopes, each fitted with powerful cameras, that would have sensitivity akin to detecting a match flame in New York City when viewed from San Francisco.
Atlas would give warnings of between one to three weeks of incoming meteorites. "That is enough time to evacuate the area of people, take measures to protect buildings and other infrastructure, and be alert to a tsunami danger generated by ocean impacts." News of the plans came as Russia revealed it was sending more than 9,000 workers to the region around Chelyabinsk in the Ural mountains where Friday's meteorite crashed. More than 50 individuals were still in hospital on Saturday night.

Russia's Meteorite Explosion Was “Heard” Half-Way Around the World - The big meteorite exploded over Russia last Friday, and while the shock waves that shot across the Internet were definitely strong, the ones that shot through the atmosphere were pretty impressive too. The blast was loud enough for infrasound sensors as far as half-a-world away to hear.
A lot of this "noise" probably wasn't audible to our human ears, which bottom out at around 20 hertz. It's still detectable though and there are dozens of facilities around the globe that have sensors devoted to detecting sounds 20hz on down. Why? Mainly to keep an ear out for possible nuke testing, which generate similar (but distinguishably different) sounds in the same range.
It shouldn't be a surprise that, at about 20 times more powerful than the nuclear weapons used in World War II, the meteorite made some noise. 11 sensors, at stations as far away as Greenland and Africa, registered the bang. It wasn't exactly on par with the most powerful nukes ever tested, but being heard continents away is definitely an accomplishment.

What are the odds of a meteor and asteroid on the same day - 1 in 100 million. Friday was an EXTREMELY UNUSUAL DAY, astronomically speaking. Just as scientists were gearing up to witness an asteroid's closest ever approach to Earth in recorded history, the sizeable meteor exploded over Russia, causing thousands of injuries.

Russian meteor strike that injured 1200 people was US weapons test, claims a prominent Russian politician. In language echoing that of the Cold War, a nationalist Russian lawmaker said: "Those were not meteorites, it was Americans testing their new weapons."
"John Kerry wanted to warn (Russia’s Foreign Minister) Lavrov on Monday, he was looking for Lavrov, and Lavrov was on a trip. He meant to warn Lavrov about a provocation against Russia." According to the politician, who is perhaps more famous for fist-fights than physics, meteorites falling on Russia is an impossibility. Referring to outer space he said: "Nothing will ever fall out there, if something falls, it’s people doing that. People are the instigators of wars, the provocateurs.”
The statements, through strident are, however, unlikely to trouble democratic relations between Russia and the US. The politician is seen as a controversial and eccentric character because of his nationalist views. As well as previously being involved in fist fights in the Russian parliament, last month he was pelted with sour cabbage during a press conference by a woman who accused him of “Ukrainophobia". He had also previously been embroiled in a row with animal rights activists over the use of a donkey to pull a sleigh in a 30-second election video.
Contrary to his theories scientists have found more than 50 tiny fragments of the meteor. The meteorites plucked from the ice-covered Chebarkul Lake so far are less than a centimetre and had an iron content of about 10%. Locals saw a big meteorite fall into the lake on Friday, leaving a six-metre-wide hole in the ice. A meteorite up to two-feet across could eventually be found in the lake. The meteor, which was travelling at around 33,000 mph rained down over the Ural Mountains. Russian health officials raised the number of those injured from the meteor's arrival to nearly 1,500 people, with 46 of them still in hospital.