The crash of the Mars spawned killer dinosaurs

The new version of the death of the dinosaurs makes a fresh look at the role of the main asteroid belt in history. Global catastrophe on Earth, which led to the mass extinction 65 million years ago, was the result of a grand clash in the depths of space the two bodies with a diameter of 40 and 170 kilometers, what happened 160 million years ago.

Modeling of the disaster and its consequences completed William Bottke (William F. Bottke) and his colleagues at the Southwest Research Institute (Southwest Research Institute), told in detail what, in his article in the journal Nature.

The prevailing theory is: the cause of death of the dinosaurs became an asteroid hit the Yucatan Peninsula on, leaving a crater Chayksalab (Chicxulub) with a diameter of 180 kilometers (details about it you can read in this article). Now the wall of the crater buried under sediment, but his mark is well "manifested" in the relief of the peninsula, if you look at it from a distance - from the satellite. In general, the impact that caused the global climate catastrophe, almost destroyed life on Earth.

Bottke and his companions tried to find out - where the asteroid came the ill-fated, and drew attention to the Baptistina asteroid family (Baptistina family), «live" in the main asteroid belt, between Mars and Jupiter. The family got its name from its main party - the asteroid 298 Baptistina, the size of 13 x 30 kilometers.

Astronomers have long calculated that this family originated 160 million years ago, when an asteroid with a diameter of 170 kilometers, hit another "Kamenyuki", about half the size. 298 Baptistina - is the biggest chip on collision.

But the question is: Baptistina family - it's all the debris created in the cosmic catastrophe? Simulated evolution of the family, the American researchers concluded that Baptistina lost so many of its members for millions of years that have passed since the death of 170-km asteroid. But where they are?

The computer showed that a long-standing clash in the asteroid belt has forced many to leave the wreckage of "home place". They began to "wander" through the solar system, including - in the vicinity of the Earth. Chemical and isotopic analysis of cosmic materials found near the crater Chayksalab showed their similarity to those materials, of which, as is well known to astronomers, the group consists Baptistina asteroids. That is ruined dinosaurs asteroid, perhaps, is one of the wreckage of a large cosmic body that collapsed 160 million years ago. "That destruction was very close to what can be called the" dynamic highway "- a way of escape from the asteroid belt - says Bottke. - Numerous flown apart from hitting the fragments left the belt, so that their impact on the inner planets was inevitable ».
Researchers say the model of spread fragments showed that the famous Tycho crater on the Moon (its age is 108 million years old, and diameter - 85 kilometers) was also created one of the asteroid impact, escaped from the family Baptistina.

In general, the analysis of the craters on Earth and the Moon shows that in the last 3 billion years, the frequency of attacks on them large cosmic bodies remained roughly the same. Except for the last 100 million years, when the frequency (for asteroids a kilometer in diameter and above) suddenly doubled against the previous (what many say is evidence).

The authors of the study believe that the destruction of the 170-kilometer asteroid that spawned Baptistina group, and is responsible for this "asteroid shower". But the probability that the "souls" is the desired source of the famous attack on the Yucatan, Bottke and his colleagues estimated at 90%.

It is curious that, according to some sources, the dinosaurs did not completely ruined Chayksalab and Shiva - the 500-kilometer crater in India, caused 300 thousand years later Yucatan. According to Gert Keller (Gerta Keller) from Princeton University (Princeton University), this crater (which is still to be explored, and in general information about him rather vague) arose when a large asteroid impact more than Yucatan. And if Chayksalab only "shaken" dinosaurs (and many other things), the Shiva them completely "finished off." So, perhaps, dinosaurs was not the only one "killer", but several.

If this theory would be correct, it does not disperse to new data Baptistina family and its role in this story. After all, "Indian guest" may also come from the same group.

However, to prove this, scientists need to collect more material for analysis as from the crater in the Yucatan and from the crater in India - from rocks corresponding to 65 million years ago. Dates when the dominance of dinosaurs came to an end.


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