We obtain the known American film “Armageddon” – very popular in the world Block Buster, which will certainly looked majority of Ukrainians as we know, it said on the Earth’s collision with an asteroid. Is it possible such a global AT ting? Any possibility it PREVENTED? About it – our conversation with Doctor of Physical and Mathematical Sciences, Head of Physics Department of the Institute of Astronomy ASTEROIDS Kharkiv National University VL.KARAZINA Dmitri LUPISHNOM.
If some day an asteroid collide with the Earth, destroying not only the human race, but millions of other living beings, and we, having the opportunity to avert disaster, do not do this to the lack of decisiveness, the false priorities, wrong assessment of the risk or poor policies, the neglect of our gift of reasonable foresight and responsibility for their own lives and all life on Earth will be the biggest act of self-denial in all of human history.
(Memorandum from the American Institute of Aeronautics and Astronautics, October 1995)
– So, we looked at an extract from the Memorandum of the American Institute of Aeronautics and Astronautics. How do you think there is a danger of exaggeration it intentionally or over-dramatization of the situation?
– Not at all. Particularly threatening us population of asteroids moving on unstable orbits near and crossed the orbit of the planet.
At present, revealed more than 1700 such asteroids (DRC), near-Earth objects. Physical properties, they differ little from other small planets orbiting in the main belt between Mars and Jupiter, except smaller in size. And yet, DRC Sisyphus that crosses Earth’s orbit, then there can be with her face, has a diameter of about 8 kilometers.
It is quite natural in recent years, major efforts of the experts is to study just such objects DRC. This risk exists throughout the history of mankind, but awareness of its reality, as already mentioned, is only now.
– But there is a probability theory. As far as the real fall to Earth asteroid? Can generally not be alert?
– We already have guided the approximate number of more or less large asteroid, say, more than 1 kilometer in diameter that cross Earth’s orbit. But there are still about 300,000 of the heavenly bodies with a diameter of more than 100 meters. Collision with the planet of each of them – is also a real danger to human existence. With decreasing size of the asteroid number is growing rapidly in line with the so-called step-law distribution of mass. Therefore, actually near the orbit of the Earth orbit the sun hundreds of thousands – millions of objects that may also fall into the planet and cause a catastrophe of local importance.
This is done as simply as redevelopment of apartments, but the devastating effects of the factor will be much worse..
Astronomers are able to simulate the evolution of the orbits of the asteroid (if it is sufficiently well defined) for hundreds of years ahead to determine the possibility of incidence of a DRC to Earth. But most of these sites, unfortunately, has not yet opened, and their orbits are not known.
Yet the probability of collision of an asteroid with the Earth is relatively small. One in a million years – for an asteroid with a diameter 2.1 kilometers, and is also one – but a hundred years, for bodies having a diameter of about ZO feet. Object similar to the Tunguska meteorite (about 60 meters in diameter), may fall to Earth once every hundred years. And yet our planet threatened by collisions with some comets, which together adds up to a maximum of 10 per cent of the DRC.
– Of course, the probability of incidence of major celestial bodies spivrozmirna with the duration of human life. But human civilization has existed for many years, and all life on earth – many hundreds of millions of years. A logical question: what happens when the Earth falls a large celestial body?
– Calculations showed that the minimum mass of an asteroid capable of causing catastrophic global climate change, flora and fauna, must be several billions of tonnes, which corresponds to the limiting diameter of 1.2 kilometers. Strike such a mass would lead to an explosion, the TNT equivalent of which reaches 1 million megatons (50 million, “Hiroshima”).
Ejection of matter from the crater could cause the effect of “nuclear winter”: dust and soot, stretched into the air, absorb solar radiation, resulting in dramatically lower the temperature of the planet’s surface, there will be global environmental change, much of the population would die within a few months or years . This apocalypse is particularly frightening that no nation will be able to help others, because the country did.
But it is extremely dangerous in a collision and body size in hundreds of meters. The main energy released at the same time with the impact of solid or liquid surface. The diameter of the crater formed exceeds the amount of body 15-20 times, and the area of the affected area, as the explosion in the atmosphere and on the surface can spread to millions of hectares. If you fall, for example, the 250-meter facility, which happens about once every 10,000 years, the zone of destruction reaches at least 1 million hectares.
American researchers have even estimated the degree of risk for the ordinary citizen to die during the life from various causes, including the planet from a collision with an asteroid or comet. Rated precisely this reason was the sixth position – after a car accident, murder, fire, electric shock, the plane crash. Is not it amazing. But the degree of risk – is the product of the probability of an event at the level of losses, and in a collision with an asteroid, they can not run into tens or hundreds of casualties and millions.
– We know that in the past on Earth has fallen large celestial body, and this has led to disasters of various scales.
On the surface of the planet survived more than 130 craters of impact (or rather explosive) origin with a diameter up to 250 kilometers of different types and ages, including very ancient detected from space.
This event coincides with a change in the two geological eras in the history of our planet: the Mesozoic and Cenozoic. It showed a mass extinction of large reptiles and dinosaurs, which gave way to mammals and birds. In the geological bowels of the earth belonging to this period, found to contain rare earth metal iridium, a hundred times greater than its concentration in the other layers. This gave grounds for a well-known geologist, Nobel laureate L. Alvatseru propose the hypothesis that the anomalous concentration and death of the dinosaurs caused by falling to Earth of a large asteroid with a diameter of 5-10 km. 150-200 км. Note that such a crater 180 km and the age of 64.98 + -0.04 million years discovered off the coast of the Yucatan peninsula (Mexico). His name – Chiskulab.
The second global cosmic catastrophe, led to the extinction of so-called “mammoth” fauna, occurred about 10 thousand years ago. Scientists suggest that after the catastrophe mankind can be reborn, at least recorded a sharp outbreak of civilization, about 8-9 thousand years ago. Thus, it becomes clear that global catastrophes strike seriously affected the development of life on earth.
– So, asteroids and comets – not a myth and not a “horror story”? And we should in this case, prepare for the worst.
Say, 23 March 1989 a previously unknown asteroid RS crossed Earth’s orbit at the point where it was only 6:00 back, passing by at a distance of about 700 thousand kilometers.
Therefore, the international community, and begins to react to this until a hypothetical danger. More than 20 years ago, in July 1981, NASA (USA) conducted the first workshop on “Collision of asteroids and comets with the Earth: physical consequences, and humanity.” Since then, the problem of asteroid and comet impact hazard has received the “official status”. Since then, the U.S., Italy and Russia were held for more than 20 international conferences, meetings, meetings of working groups devoted to this problem. Realizing that the first priority in its decision is the identification and cataloging of asteroids located near the earth’s orbit, the astronomers of the U.S., Europe, Australia and Japan have developed and implemented several of the observational programs. Prior observations of asteroids and comets are increasingly attached astronomers and other countries.
– And what a contribution to this common cause can make Ukrainian astronomers?
СССР. Thus, the Crimean Astrophysical Observatory installed a dedicated 64-centimeter telescope to search for new fast-moving objects (DRC) and monitor them with the accrual of their coordinates in real time. For 25 years, leads a program of observations DRC in order to study their physical properties and our institute. Scientific results of these studies are known abroad and some international colleagues have expressed the view that the Kharkov group – one of the most productive in Europe.
By the way, the international definition of our achievements demonstrated by the fact that in 2001 the Czech astronomers have named an asteroid they discovered the name of 15,898 Kharasterteam (abbreviated from Kharkiv asteroid team – Kharkiv asteroid team). Additionally, in Kiev and Kharkov, there are recognized experts on the physical characteristics of comets and meteor matter.
– Can a person in the near future to prevent the decline of large celestial body to Earth?
– Yes. And here there are various technical options for, say, the destruction of an object or change its trajectory. The latter option can be accomplished by providing an asteroid more speed, bombed at the surface or dropping off her stuff, scattering a cloud of dust on the trajectory of its motion. However, there are also other proposals.
– Since the new vseplanetarnogo Armageddon would not be?
– Yes, it will not, but only when humanity is united to confront the real asteroid and comet impact hazard