American researchers have a new theory about how an object hit the Earth and caused the death of dinosaurs.
Scientists largely agree on where impact it happened about 65 million years ago. They say a huge object hit an area off the coast of what is now Mexico. Astronomers said the most likely cause of the strike was either a asteroid or a comet.
In recent years, researchers have presented evidence that the impact was caused by an asteroid. The theory suggests that the asteroid came from an area between the orbits of Mars and Jupiter.
But a study by two astronomers at Harvard University presents a new theory: that the collapse was caused by a comet. Researchers say the comet came from an area that contains ice scrap on the edge of the solar system. The area is known as the Oort Cloud.
Their theory states that the comet was drawn into the solar system by Jupiter’s gravity. The comet then came very close to the sun, whose tidal force he tore it to pieces. Researchers believe that one of the pieces collapsed in the place that scientists identified in Mexico.
The team based their theory on a model created to predict the probability of a long-range comet in the Oort cloud hitting Earth. Long-range comets take more than 200 years to orbit the Sun.
Because comets come from frozen areas of the outer solar system, they are more frozen than asteroids. They are known to leave long traces of gas and dust as they melt.
The new study was recently published in Scientific reports. The lead author was Amir Siraj, a Harvard astrophysics student. “Jupiter is so important because it is the most massive planet in our solar system,” he told French news agency AFP.
Siraj said the findings showed that Jupiter’s large influence pushes “these long-lasting comets into orbits that bring them very close to the sun.” Comets experience a tidal force so great from the sun “that the most massive of them would do it shatter in about a thousand Scraps“Each of these fragments would be large enough to produce a crater the size of the Mexican site, he added.
It is estimated that this massive impact was equal to the power of about 10 billion nuclear bombs. The US space agency NASA estimated that the strike created a huge crater about 180 kilometers wide and 900 meters deep.
The event is believed to have caused fires, earthquakes and widespread ocean waves. It also released chemicals into the atmosphere, leading to severe cooling. Scientists blame the event for destroying more than 70% of plant and animal life. In addition, all non-bird-like dinosaurs have disappeared.
The researchers say their theory can be tested by further studying the crater in Mexico, as well as possibly those on the moon. In addition, space explorers could also be sent to collect comet material for examination.
The study also suggests that similar impacts can be expected to hit the Earth about once every 250-730 million years. But the other lead researcher on the project, Harvard professor Avi Loeb, noted that this is only an estimate.
“You never know when the next one will come,” he said. “The best way to find out is to look for the sky.”
I’m Bryan Lynn.
Bryan Lynn wrote this story for Learning English, based on reports from Agence France-Presse and The Harvard Gazette. Mario Ritter, Jr. was the editor.
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Words in this story
impact – n. an act or event in which something strikes another
asteroid – n. a space rock, which can be small or the size of a large moon, orbiting the sun
comet – n. an object in outer space that is made of material such as gas and ice, which is left behind in its orbit as it approaches the sun
scrap – n. pieces that are left after something falls apart
tidal force – n. a secondary gravitational force involving two objects
shatter – V. to break suddenly into many pieces
fragment – n. a broken piece of something that was once bigger
crater – n. a round hole made by an explosive force, such as a bomb or an object falling from the sky