New data from asteroid Bennu still suggests possible threat to Earth

US space agency NASA says new data from observations of the asteroid Bennu still suggests that the object might one day hit Earth.

But, scientists studying the asteroid are predicting in a new study that Bennu is unlikely to hit Earth in centuries to come.

Bennu and other asteroids are considered near-Earth objects (NEO). Scientists identify such objects as those with the possibility of being within 50 million kilometers of Earth’s orbit.

Bennu was discovered in 1999. It is believed to have formed during the first 10 million years of our solar system’s history, over 4.5 billion years ago. It moves in near-Earth space due to gravitational interactions with other planets. It also absorbs heat from the sun which provides extra boost. Bennu makes his closest passage to Earth every six years.

The latest data on Bennu was collected by NASA’s Osiris-Rex spacecraft, which spent more than two years observing the asteroid. Last October, Osiris-Rex also successfully collected samples by Bennu. The spacecraft is now on its return trip to Earth, with NASA expecting its arrival in September 2023.

The main objective of the Osiris-Rex mission was to collect the samples. Scientists say they hope the material can help them better understand how planets formed and how life began on Earth.

But new data from Osiris-Rex also gave scientists a better idea of ​​Bennu’s current and future movements, including the chances he could strike Earth. The new details recently emerged in a study of the publication Icarus.

One of the study’s findings is a prediction that Bennu will pass close to Earth in 2135. At that time, scientists say the asteroid will pass Earth within half the distance of Earth. at the moon.

Prior to the Osiris-Rex mission, researchers estimated the odds of Bennu hitting Earth in the year 2200 to be 1 in 2,700. With the new data, scientists believe the odds are 1 in 1,750, up to ‘in 2300.

Even though the new prediction increases the odds of a hit by Bennu, NASA researchers who spoke to reporters about the discovery said people shouldn’t be too worried.

“We shouldn’t be too worried about this,” said Davide Farnocchia, the study’s senior writer. He is a scientist at NASA’s Center for Near Earth Object Studies at the Jet Propulsion Laboratory (JPL) in California.

Farnocchia noted that Bennu’s risk “is smaller than that of the undiscovered population of objects of similar size.” He added that “overall things have improved” because scientists now have a much better idea of ​​Bennu’s journey.

Lindley Johnson is NASA’s planetary defense officer. He was asked about the destruction that could result from a possible strike by Bennu. He said one hit wouldn’t destroy all life on Earth. But the event would create a crater about 10 to 20 times the size of the asteroid. Bennu is believed to be around 500 meters wide.

Johnson added that the total area of ​​destruction at once would be much larger, covering an area up to 100 times the size of the crater. He noted that there may be other as yet undiscovered objects that may pose a greater threat.

“We’re still looking for what we don’t know out there – items that haven’t been found yet,” Johnson said. He noted that the researchers were also studying ways to redirect an asteroid’s orbit should that become necessary.

But Johnson added: “We really don’t think we need to do anything about Bennu.”

I am Bryan Lynn.

Bryan Lynn wrote this story for VOA Learning English based on reports from NASA, The Associated Press, Agence France-Presse, and Icarus. Hai Do was the editor.

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Words in this story

asteroid – nm one of the many large rocks that surround the sun

to taste – not. a small amount of something that gives you information about the thing it was taken from

mission – not. a flight performed by an aircraft or spacecraft to perform a specific task

crater – not. a round hole made by an explosive force such as a bomb or an object falling from the sky