Attack top

Attack top

The probability that a large asteroid will fall into the ocean, not on land, much more, because 70 percent of the Earth’s surface is covered by water. The result can be catastrophic: a powerful explosion can cause such a tsunami that we can hardly imagine. The figure shows the approach of the asteroid, its fall and the emergence of giant waves. On the coast tsunami descend hundreds of meters: they are about to take down the shore a tiny lighthouse.

At first, 120-meter high tsunami waves. Then rain from nitric acid — the reaction product of oxygen, nitrogen and steam in the superheated air. Finally, long-term continuous winter fault of the fine dust that hangs in the stratosphere and block the path of the sun.

This scenario has long predicted by astronomers and geophysicists, explains how a relatively small on space standards asteroid — just two kilometers in diameter — can put an end to the history of civilization.

Back in 1994, for a review in the prestigious scientific journal «Naturi» Astrophysics calculated that the probability that a meteorite arrives on Earth in the twenty-first century — 1:10 000. This is 150 times greater than the risk of death in a plane crash. But aerophobia offer special psychological courses, which are taught not to be afraid of air travel, and the fear of asteroids appears eccentricity, excusable unless the teenager, after reading science fiction.

But when the National Aerospace Agency of the US Congress proposes to spend on combating the threat of asteroid several billion dollars — is another matter.

This summer, PASA issued a detailed plan for the upcoming mission. Three years takes casting: many thousands of asteroids will choose the ideal candidate. Requirements tough, just like in the fashion industry — weighs about 500 tons, diameter from seven to ten meters, «residence» in a certain area of ​​the solar system. In 2017, to send a robot-interceptor — Unmanned spacecraft equipped with special bags, which seamlessly fit a five-story staircase. By the end of 2019 the robot with an asteroid, packed in a bag, supposed to take the opposite course.

Location limit of 500 tonnes and ten meters? Everything rests on the power of the tug. To peretaskivatSnachala 120-meter tsunami wave. Then rain from nitric acid — the reaction product of oxygen, nitrogen and steam in the superheated air. Finally, long-term continuous winter fault of the fine dust that hangs in the stratosphere and block the path of the sun.

This scenario has long predicted by astronomers and geophysicists, explains how a relatively small on space standards asteroid — just two kilometers in diameter — can put an end to the history of civilization.

Back in 1994, for a review in the prestigious scientific journal «Naturi» Astrophysics calculated that the probability that a meteorite arrives on Earth in the twenty-first century — 1:10 000. This is 150 times greater than the risk of death in a plane crash. But aerophobia offer special psychological courses, which are taught not to be afraid of air travel, and the fear of asteroids appears eccentricity, excusable unless the teenager, after reading science fiction.

But when the National Aerospace Agency of the US Congress proposes to spend on combating the threat of asteroid several billion dollars — is another matter.

This summer, PASA issued a detailed plan for the upcoming mission. Three years takes casting: many thousands of asteroids will choose the ideal candidate. Requirements tough, just like in the fashion industry — weighs about 500 tons, diameter from seven to ten meters, «residence» in a certain area of ​​the solar system. In 2017, to send a robot-interceptor — Unmanned spacecraft equipped with special bags, which seamlessly fit a five-story staircase. By the end of 2019 the robot with an asteroid, packed in a bag, supposed to take the opposite course.

Location limit of 500 tonnes and ten meters? Everything rests on the power of the tug. To drag the cosmic body from orbit to orbit, NASA engineers have proposed the engine 70 horsepower. Less than in a modest SUV — really for space could not find anything better? The difficulty is that the robot, unlike a car, you need to haul an asteroid without refueling and a break for almost three years in a row. And only suitable for this source of energy — solar panels. If in the next year or two cases of sudden breakthrough in solar energy in the world — the battery will become easier, more flexible and effective — it will help wipe in space on the larger stone. Asteroid need to be towed to a close but safe distance — slightly more than the moon — and made to rotate around the Earth. There, in the orbit of his in 2021 and visit the astronauts in the capsule of the new spacecraft «Orion». This will be the most distant expedition in history: since 1972, the last time when men landed on the moon, all operations in space are just 400-600 km from Earth.

The crew of the «Orion» is waiting for a fairly modest task — only to take the sample and return to Earth. But this mission rehearsal for more serious: for example, once the astronauts might need to undermine the right space rock that break the course is not easy.

Traces of previous clashes, scattered across the planet, and remind the reality of the threat and its scale. Since the time of the dinosaurs to Earth crashed at least six hundred kilometer countless meteorites and cosmic projectiles smaller.

In the middle of the Arizona desert in the United States, near the town of Flagstaff, tourists show a giant hole depth of 170 meters and a diameter of 1200. The pictures from space, it looks exactly like a lunar crater, and the first impression does not deceive: a crater can leave behind only a meteorite. Calculations say that it was the size of a little more than 12 etazhki, composed of iron and nickel, and crashed into the Earth 50,000 years ago. By this time, the first Homo sapiens have moved from Africa to explore Asia. And just because to America they have not yet reached, in the collective memory of humanity — any myths or fairy tales — there is no history of an explosion in the desert, ranging from 20 to 40 megatons.

Chicxulub crater on the Yucatan Peninsula in Mexico, with a diameter of 180 kilometers survived worse, if only because he’s in more than a thousand times over. For 65 million years of erosion and other geological processes have smoothed relief on land, and a bowl of the crater more than half went under water Gulf of Mexico. There, under the water, the oil company geologists and found in 1978, surprising arc of regular shape — the surviving part of the shaft, which was formed by the explosion caused by the collision with the Earth ten-stone.

That is the explosion — about ten billion times more powerful than Hiroshima — killed the dinosaurs. And with them, and a significant portion of all life on the planet (paleontologists use the ominous term «Cretaceous-Paleogene extinction event»). On a day when the meteorite hit the ground, over the Mesozoic era lasting almost 200 million years. And Cenozoic began, continues to this day.

Where are cosmic shells and where they have so much energy? Right meteorite called each of them receives in the last few seconds of his life — not before thundering enters the Earth’s atmosphere. A meteorite is a future peacefully traveling through outer space, astronomers call it an asteroid, or «minor planet». These are found in the solar system, where most of these «big», planets. The largest asteroid Ceres is about 950 kilometers in diameter: this is 13 times less than the Earth, and is 3.5 times less than that of the moon. A diameter greater than 100 kilometers boast two hundreds asteroids.

Most astronomers interested in the asteroids, which are able to get close enough to the Earth. These «near-Earth objects» — the subject of careful observation of NASA and other space agencies. In January 1995, they were known to only three hundred, and in June, the 2013th officially announced the opening of ten thousand.

Back in 1998, the US Congress has entered the search for «near-Earth objects» in a separate line in the state budget of the United States. Since then, the game includes several research centers scattered around the world. The most prolific — Review of Catalina (telescopes installed in the United States and Australia) and the system of telescopes in Hawaii. According to astronomers, a year ago, 90 percent of «near-Earth objects» larger than a kilometer in diameter were discovered and described. Is not in the list has just a few dozens.

The trajectory of each is counted known for many years to come — and only in 1410 recognized as «potentially dangerous»: they can come closer to the Earth than seven million kilometers and have more than 150 meters in diameter. However, any «near-Earth objects», which is more than one chance in a thousand hit the ground, not in the list. So, nothing to worry about? Certainly not.

An idyllic picture of the cosmos where all the risks calculated primarily spoils Yarkovsky effect described over a hundred years ago — long before science took asteroid threat seriously. In 1900, the railway engineer from St. Petersburg, who was interested in astronomy in his spare time, put forward the idea: the celestial bodies may go astray from the fact that the sun warms them with just one hand.

Heat released by the heated part of the cosmic stone into space as infrared radiation, working like a jet output and takes the stone to the side. In 2003, NASA’s Jet Propulsion Laboratory using radar confirmed that is the case: in 12 years of observation, 530-meter asteroid 6489 Golevka evaded calculated orbit by as much as 15 kilometers.

What prevents pick up and play Yarkovsky effect in the equation to predict the orbit? The lack of data: Astronomers do not know, for example, quickly whether the asteroid is spinning around its axis, or the color of the surface. When the monitoring system observes another dangerous object, it’s just a bright dot on a computer screen — and only. The most powerful telescopes are powerless to add to her description of the new parts, if before the asteroid 100 million kilometers, while its own diameter — 100 meters. It’s like trying to read a single letter in the journal, forgotten on a table in a cafe, watching him from the International Space Station.

If the Earth did not see, it is to equip the expedition. In 1996, NASA sent an unmanned probe «Shoemaker» to the asteroid 433 Eros: the one of the first in the list of «near-Earth objects», open astronomers. Stretched 34-kilometer-long stone shape which some scientists compare the potato, and others — with a pod of peanut every ’81 coming to Earth at a distance of a few millions of kilometers and becomes brighter planet Neptune. It weighs about as much as, and Chiksulubsky asteroid that killed the dinosaurs. The surprise for the scientists was the even that a monolithic block, instead of piling up of debris. Constant collisions of asteroids with each other have to split them apart. However, because the process takes place in a vacuum, where there is no place to fall, the mutual attraction finally collects fragments back together. Visible through a telescope pile of stone chips held by barely perceptible force of gravity does not differ from the monolith.

It is this «pile of trash» found the Japanese probe «Hayabusa» (in Russian «Peregrine»), which in May 2005 explored the asteroid 25143 Itokawa. For the first time in the history of the probe collected from the surface of a few microscopic particles and bring them back to Earth. Chemists claimed that the material held on the surface of a celestial body is too little time — a total of eight million years. So, before it was hidden in the depths of another asteroid, which as a result of unknown cosmic incident broke. But Itokawa was formed from the debris.

Asteroid-feeding is not an example dangerous asteroids monolith — like a bomb stuffed with bolts, more dangerous than bullets. It is necessary to unleash «pile» as follows, and stones fly in different directions — each in its unpredictable trajectory. For the promotion of responsible special kind Yarkovsky effect, YAORP effect. A team of astronomers from the Czech Republic, the United Kingdom and the United States found that if the asteroid does an hour five turns around its own axis, thanks YAORP effect can turn into enraged centrifuge revolving at a speed of 180 revolutions per hour. Minor planet, the example that was shown, even renamed in honor of the study — now called 54509 YAORP.

Imagine that a massive asteroid flies a direct course for Earth. Clashes can not be avoided. And in the bag interceptor robot he did not fit. What methods of struggle have left the scientists? The most different — from thermonuclear warheads to patient Paint guns. Back in 2007, NASA disassemble most of them in the report to the US Congress.

It would seem that the thermonuclear bomb a hundred megatons — the universal answer to all threats. Powerful explosion — and debris flying in all directions. And then going to the «pile of garbage» and continue to fly towards Earth. It may not turn from the path just a few — but now it is no longer a lump of a ten and a dozen stones kilometer in diameter.

«Paintball» scenario has a common point with the fusion: also requires firing. But no missiles with nuclear warheads, and balls of paint. It is enough to whiten the asteroid on the one hand — and the Sun will take over the work of the tug: the pressure of light would lead to a dangerous stone track. But it remains unclear mass. For example, how much paint will be spent on a spot the size of a football field? First, this figure should be multiplied by the cost per kilogram of cargo space (thousands of dollars). Then ask — can help greatly if the pressure of light, if an asteroid opened yesterday and is scheduled for the day after the collision?

The smaller stone — the less time he leaves food for thought, because to detect small celestial bodies can be achieved only on the approach to the Earth. The only meteorite fall which had been predicted in advance — a 80-ton 2008 TAP, exploded October 7, 2008 in the Nubian desert in Sudan. The astronomer Richard Kowalski made it into the list of 20 hours before the entry of the object into the atmosphere. Surely there were chances to be seen and the Chelyabinsk meteorite weighing ten thousand tons, astronomers do not be passionate about the expectation of another «near-Earth objects,» or similar sizes. On the same day an asteroid called 2012 DA14 flew only 28 thousand kilometers from Earth — closer than the orbit are most communication satellites.

But apart from asteroids in space full of exotic — and dangerous — tel, a meeting which did not predskazhesh. Astrophysicists believe that the first minutes after the Big Bang space flooded with microscopic black holes, that’s just where to find them, no one knows. Microscopic — it is about scale, but not about the weight. A hole the size of a bacterium can weigh hundreds of millions of tons. The word «black» is not quite accurately describes the situation: such objects should emit Hawking radiation is bright — but what is a bacterium, even bright, when viewed from a distance of a million kilometers? The main difference from the asteroid that such a black hole can easily penetrate through the Earth, and even the sun — like a bullet that gets into a snowman.

Two astrophysicists at Princeton and New York University offered a way to find out how often does this sort bullets whistling over his head. Astronomers love the metaphor of «cosmic shooting gallery», where the target celestial bodies hung side-by-side. According to this metaphor, to find out the frequency of meteorites hit the Earth, it is enough to count the craters on the moon — the density of cosmic bombardment about the same. A monitoring of microscopic black holes useful to follow the sun — it is also a target. Once a tiny black hole gets into it, the spectrum of light for a split second to change.

And then our fears will add another official.

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