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Threats in space
Asteroid Apophis can wipe us off the face of the Universe. It was named to honor the ancient Egyptian god of darkness and destruction. Discovered in 2004 asteroid’s size corresponds a skyscraper and weighs 20 million tons.

Whiz at speeds hundreds of times faster than a bullet, it is not a lower energy than all the nuclear weapons on the planet. Astronomers around know where it goes. According to their calculations, in April 2029 a huge boulder will fly in 34-36 thousands of miles from the Earth’s surface. This is close enough for the satellites in low Earth orbit, so this event is already dangerous. April 13, 2036 Apophis could collide with the Earth, said that date Professor of St. Petersburg State University, Leonid Sokolov. Fortunately, the likelihood that Apophis will fall on us, is extremely small, since the approach to our planet, will it break into pieces.
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Mass death of herring in Kvænes, northern Norway, found on the morning of New Year’s Eve. Estimates say there’s 20 tons of dead fish. No one knows why they’re dead (or rather, why they’re beached), but possible causes include washing ashore during a recent storm, being chased by predatory pollock, or getting trapped by a current.
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The Tunguska event, or Tunguska blast or Tunguska explosion, was an enormously powerful explosion that occurred near the Podkamennaya Tunguska River in what is now Krasnoyarsk Krai, Russia, at about 7:14 a.m. on June 30, 1908. The explosion is believed to have been caused by the air burst of a large meteoroid or comet fragment at an altitude of 5–10 kilometres (3–6 mi) above the Earth’s surface. Different studies have yielded varying estimates of the object’s size, with general agreement that it was a few tens of metres across. The number of scholarly publications on the problem of the Tunguska explosion since 1908 may be estimated at about 1,000 (mainly in Russian). Many scientists have participated in Tunguska studies, the best-known of them being Leonid Kulik, Yevgeny Krinov, Kirill Florensky, Nikolai Vladimirovich Vasiliev and Wilhelm Fast. Although the meteoroid or comet burst in the air rather than hitting the surface, this event is still referred to as an impact. The behaviour of meteorites in the Earth’s atmosphere was less well understood during the early decades of the 20th century. Due to this, as well as the paucity of relevant data resulting from Soviet secrecy during the Cold War, a great many other hypotheses for the Tunguska event have sprung up, none of which are accepted by the scientific community.
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The Andromeda–Milky Way collision is a predicted galaxy collision that could possibly take place in approximately 3 to 5 billion years’ time between the two largest galaxies in the Local Group—the Andromeda Galaxy and the Milky Way, which contains Earth. Each galaxy contains over a hundred billion stars, which is 100 million trillion possible collisions. Nevertheless, the chance of even two stars colliding is negligible because of the huge distances between them. For example, the nearest star to the Sun is Proxima Centauri, about thirty million solar diameters away. If the sun were a ping-pong ball in Paris, the ping-pong-Proxima would be in Berlin and our galaxy would be 12 million miles wide—about a third of the distance to Mars. Stars are much denser near the galactic centers—the average separation is only 100 billion miles. But that is still a density of one ping-pong ball every two miles.
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Late heavy bombardment
The late heavy bombardment is a period of time approximately 4.1 to 3.8 billion years ago (Ga) during which a large number of impact craters are believed to have formed on the Moon, and by inference on Earth, Mercury, Venus, and Mars as well. The evidence for this event comes primarily from the dating of lunar samples, which indicates that most impact melt rocks formed in this rather narrow interval of time. While many hypotheses have been put forth to explain a “spike” in the flux of either asteroidal or cometary materials to the inner solar system, no consensus yet exists as to its cause. The Nice model popular among planetary scientists postulates that the gas giant planets migrated in orbit at this time, causing objects in the asteroid belt and/or Kuiper belt to be put onto eccentric orbits that reached the terrestrial planets. Nevertheless, some argue that the lunar sample data do not require a cataclysmic cratering event near 3.9 Ga, and that the apparent clustering of impact melt ages near this time is an artifact of sampling material affected by a single large impact basin.
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While scientists are confident a large asteroid crashed into Earth approximately 65 million years ago, leading to the extinction of dinosaurs and some other life forms on our planet, they do not know exactly where the asteroid came from or how it made its way to Earth. A 2007 study using visible-light data from ground-based telescopes first suggested the remnant of a huge asteroid, known as Baptistina, as a possible suspect. According to that theory, Baptistina crashed into another asteroid in the main belt between Mars and Jupiter about 160 million years ago. The collision sent shattered pieces as big as mountains flying. One of those pieces was believed to have impacted Earth, causing the dinosaurs’ extinction.
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The tsunami caused by the 11 March Tohoku earthquake in Japan crossed the Pacific and broke off large chunks of ice from Antarctica, a study has shown. Satellite photos show huge icebergs were created when the tsunami hit West Antarctica’s Sulzberger Ice Shelf. This caused 125 sq km of ice to break off - or calve - from a shelf front that has remained stable for the past 46 years.
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Japanese repair quake-ravaged road in just six days. Due to the extensive damage in Japan caused by the massive earthquake and resultant tsunami on March 11, many have questioned if the island nation can recover in a year, much less a few months. If the swiftness with which the Japanese can repair roads is any indication, we wouldn’t bet against the country cleaning up this catastrophe in short order.
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It’s Lake Shore Drive in Chicago at 02.02.11 in the morning after over a foot of snow fell overnight in the Windy City on Lake Michigan.
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Extinction event
An extinction event is a sharp decrease in the diversity and abundance of macroscopic life. They occur when the rate of extinction increases with respect to the rate of speciation. Because the majority of diversity and biomass on earth is microbial, and thus difficult to measure, recorded extinction events affect the easily observed, biologically complex component of the biosphere rather than the totaldiversity and abundance of life.
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High-resolution aerial photos taken over Brisbane last week have revealed the scale of devastation across dozens of suburbs and tens of thousands of homes and businesses. The aerial photos of the Brisbane floods were taken in flyovers on January 13 and January 14.
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