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Blue whale-sized asteroid has passed Earth |
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An asteroid the size of a blue whale, the largest animal on Earth, passed by Earth.
According to the National Aeronautics and Space Administration (NASA), the asteroid ‘2015 FF’ with a diameter of about 28 meters passed the nearest point to Earth at 5:09 pm (Korean time) on the 12th.
Similar in length to a blue whale
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The asteroid, first discovered in 2015, passed as expected about 4.3 million kilometers from Earth at a speed of 33,000 kilometers per hour, which is 27 times the speed of sound. / photo = NASA |
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The asteroid, first discovered in 2015, passed as expected about 4.3 million kilometers from Earth at a speed of 33,000 kilometers per hour, which is 27 times the speed of sound. It is eight times the average distance between the Earth and the Moon, but from an astronomer’s point of view, it is just around the corner.
Previously, NASA classified the asteroid as a Potentially Hazardous Asteroid (PHA). However, he said there is no risk of a collision when approaching Earth this time. The next visit to the asteroid will be on August 19, 2066, 44 years later.
What are the potentially dangerous asteroids?
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Potentially dangerous asteroid image/photo=NASA |
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NASA defines objects within a range of about 193 million km from Earth as near-Earth objects (NEOs) that are likely to collide with Earth. In addition, asteroids with a minimum crossing distance of about 7.48 million km or less with Earth’s orbit and moving at high speed are classified as potentially dangerous asteroids.
NASA is currently tracking the positions and orbits of more than 28,000 asteroids through the Asteroid Impact Final Warning System (ATLAS). ATLAS, which observes the entire night sky every 24 hours with four telescopes, has found over 700 near-Earth objects and 66 comets since its first operation in 2017.
Two of those asteroids actually hit Earth. ‘2019 MO’ exploded off the south coast of Puerto Rico, and ‘2018 LA’ fell on the area near the border between Botswana and South Africa, but fortunately no damage was done.
No asteroids to threaten Earth within 100 years
NASA has estimated the orbits of all near-Earth objects it has ever discovered. As a result, fortunately, there are no asteroids that will threaten the Earth within the next 100 years.
Nevertheless, national space agencies say they should continue to monitor asteroids. Because dangerous asteroids that we missed could suddenly be discovered.
In fact, an asteroid the size of a bowling ball that exploded over Vermont on March 7, last year, was not previously discovered. At that time, the explosive power was strong enough to be equivalent to 200 kg of TNT explosives.
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In 2013, an asteroid exploded over Chelyabinsk, central Russia. / photo = YouTube |
Earlier, the destructive power of an asteroid that exploded in mid-air in Chelyabinsk, central Russia in 2013 was much greater. This is because the energy released from the Hiroshima atomic bomb was 2,633 times that of the Hiroshima atomic bomb, damaging many nearby buildings and injuring more than 1,200 people.
Collision must be prepared
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An image of the DART spacecraft approaching to collide with the asteroid Didymos. / photo = NASA |
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What should you do if an asteroid lands on the Earth? To prepare for the day when this situation becomes a reality, space agencies in each country are preparing to defend the Earth.
The main mission of the NASA probe DART, launched on November 24 last year, is to test whether it can change its orbit by impacting the asteroid Didymos around this fall.
China is also planning a similar mission. The plan is to launch 23 Changjeong 5 rockets towards the asteroid Benu. Benu is known as an asteroid with a potential to hit Earth by 2199.
By Yoon Tae-hee, staff reporter [email protected]
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