100 full moons: Blazing fireball lights up Arctic sky

In this March 17, 2013 file photo, the Aurora Borealis bright up the sky at twilight between the towns of Are and Ostersund, Sweden. AFP PHOTO/JONATHAN NACKSTRAND
Updated 18 November 2017
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100 full moons: Blazing fireball lights up Arctic sky

COPENHAGEN, Denmark: A blazing fireball lit up the dark skies of Arctic Finland for five seconds, giving off what scientists said was “the glow of 100 full moons” and igniting hurried attempts to find the reported meteorite.
Finnish experts were scrambling to calculate its trajectory and find where it landed, according to Tomas Kohout of the University of Helsinki’s physics department, who said Thursday night’s fireball “seems to have been one of the brightest ones.”
It produced a blast wave that felt like an explosion about 6:40 p.m. and could also be seen in northern Norway and in Russia’s Kola peninsula, he told The Associated Press on Saturday.
It might have weighed about 100 kilograms (220 pounds), according to Nikolai Kruglikov of Yekaterinburg’s Urals Federal University.
“We believe it didn’t disintegrate but reached a remote corner of Finland,” Kohout said, adding that any search plans for the meteorite must face the fact that “right now we don’t have much daylight” — four hours, to be precise.
The Norwegian meteorite network said the fireball “had the glow of 100 full moons” and likely was going northeast, perhaps “to the Norwegian peninsula of Varanger,” north of where the borders of Russia, Finland and Norway meet.
Kohout said scientists looked forward to any space debris they can get their hands on.
“We are happy to recover (it) since this is a unique opportunity to get otherwise inaccessible space material,” said Kohout. “This is why it’s worth it to search for them.”
Viktor Troshenkov of the Russian Academy of Sciences told the Tass news agency that the fireball could be part of a prolific meteor shower known as the Leonids, which peaks at this time of year. He said he felt Thursday’s fireball likely wasn’t the sole meteorite but others maybe were not seen due to thick clouds elsewhere.
Troshenkov told Tass that meteor showers can be even stronger. The Leonids reach their maximum once every 33 years — and the last time that happened was in 1998, he said. Amateur astronomers in the Arctic then saw about 1,000 meteors, 40 meteorites and one fireball in just one night.
In 2013, a meteorite streaked across the Russian sky and exploded over the Ural Mountains with the power of an atomic bomb, its sonic blasts shattering countless windows and injuring about 1,100 people. Many were cut by flying glass as they flocked to windows, curious about what had produced such a blinding flash of light.
The 2013 Chelyabinsk meteorite was estimated to be about 10 tons when it entered the Earth’s atmosphere at a hypersonic speed of at least 54,000 kph (33,000 mph). It shattered into pieces about 30-50 kilometers (18-32 miles) above the ground but some meteorite chunks were found in a Russian lake.
A meteoroid is smaller than a kilometer (0.62 mile), and often so small that when it enters the Earth’s atmosphere it vaporizes and never reaches the ground. A meteor is a flash of light caused by a meteoroid that fails to get through the Earth’s atmosphere. If part of it does survive, that’s called a meteorite.
Asteroids are generally larger chunks of rock that come from the asteroid belt located between the orbits of Mars and Jupiter.


Massive diamond cache detected beneath Earth’s surface

Updated 18 July 2018
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Massive diamond cache detected beneath Earth’s surface

  • “This shows that diamond is not perhaps this exotic mineral..."
  • These naturally occurring precious minerals are located far deeper than any drilling expedition has ever reached

WASHINGTON: There’s a load of bling buried in the Earth.
More than a quadrillion tons of diamonds to be exact — or one thousand times more than one trillion — US researchers at the Massachusetts Institute of Technology reported this week.
But don’t expect a diamond rush. These naturally occurring precious minerals are located far deeper than any drilling expedition has ever reached, about 90 to 150 miles (145 to 240 kilometers) below the surface of our planet.
“We can’t get at them, but still, there is much more diamond there than we have ever thought before,” said Ulrich Faul, a research scientist in MIT’s Department of Earth, Atmospheric, and Planetary Sciences.
“This shows that diamond is not perhaps this exotic mineral, but on the scale of things, it’s relatively common.”
Using seismic technology to analyze how sound waves pass through the Earth, scientists detected the treasure trove in rocks called cratonic roots, which are shaped like inverted mountains that stretch through the Earth’s crust and into the mantle.
These are “the oldest and most immovable sections of rock that lie beneath the center of most continental tectonic plates,” explained MIT in a statement.
The project to uncover deep Earth diamonds began because scientists were puzzled by observations that sound waves would speed up significantly when passing through the roots of ancient cratons.
So they assembled virtual rocks, made from various combinations of minerals, to calculate how fast sound waves would travel through them.
“Diamond in many ways is special,” Faul said.
“One of its special properties is, the sound velocity in diamond is more than twice as fast as in the dominant mineral in upper mantle rocks, olivine.”
They found that the only type of rock that matched the speeds they were detecting in craton would contain one to two percent diamond.
Scientists now believe the Earth’s ancient underground rocks contain at least 1,000 times more diamond than previously expected.
Still, very few of these gems are expected to make their way to the jewelry store.
Diamonds are made from carbon, and are formed under high-pressure and extreme temperatures deep in the Earth.
They emerge near the surface only through volcanic eruptions that occur rarely — on the order of every few tens of millions of years.