In the vast universe, there are countless asteroids, each of them has a unique geological characteristics and potential value.Among them, an asteroid called Benu has attracted great interest among scientists because it is believed to be one of the oldest asteroids in the solar system, with an age of 4.5 billion years.The asteroid is rich in carbon and water, providing a valuable resource and research opportunity for mankind.
Benu is a small asteroid with a diameter of about 500 meters and a mass of about 2.31× 1019kg.According to scientists, Benu’s formation dates back to the early days of the solar system, when dust and gas in the solar system gradually gathered under the influence of gravity to form the asteroid belt.Benu is one of the many asteroids born in this process.
The first asteroid sampling probe in the United States, Osiris-R E x, delivered a sample of the asteroid Benu to Earth in September 2023, and the sample, weighing about 250 grams, was sent to Johnson Space Center.It is studied by staff in protective clothing in purpose-built dust-free cleanrooms.In the small sample studied, the percentage of carbon was nearly 5 percent by weight, Nelson said, the highest percentage of meteorites and other extraterrestrial material reaching Earth that NASA researchers have examined.This carbon is present “in the form of organic molecules and minerals.”In addition, the sample contains a large number of water molecules, which are “locked” into the crystalline structure of the clay fibers.
Benu’s age makes it an important object for studying the early evolution of the solar system.Through radioisotope analysis of Benu’s rock samples, scientists found that Benu contained a large amount of carbon-14 isotopes, meaning it had been absorbing carbon from Earth for the past 4.5 billion years.The discovery confirms the idea that extraterrestrial matter exists in the solar system and provides a new perspective on Earth’s evolution.
In addition, Benu is considered one important source of water in the solar system.;Scientists have found large amounts of water-laden rocks on Benu’s surface, where water molecules exist in the form of ice.By analyzing the spectra of the rocks, scientists found that Benu’s surface contained much more water than expected, suggesting that Benu may have had liquid water in the past.
“We think that’s how water gets to Earth.”Dante Lauretta, a professor of planetary science at the University of Arizona and research director for the Osiries-REx mission, said,”The reason the Earth is habitable, and we have oceans, lakes, rivers, and rain, is because these clay minerals came to Earth between four and 4.5 billion years ago, making our world habitable.”So what we’re seeing is how water blends into solid matter.”
Lauretta added that the researchers also found sulfide minerals and iron oxide minerals in the samples.Sulphide minerals are “key elements in planetary evolution and biology,” while iron-bearing minerals in the form of iron sulfide and iron oxide “indicate in themselves that they were formed in a water-rich environment.”
The asteroid Benu, discovered in 1999, is about 490 meters in diameter and approaches Earth every six years.Scientists say a carbonaceous asteroid like Benu, which struck Earth early in its formation and brought with it elements such as water, may contain mineral fragments from nearly 4.6 billion years ago and may even provide clues to the origin of life.In addition, because Benu’s orbit almost intersects the Earth, American astronomers predict that it may have flown over the Earth at close range around 2182.By studying these samples, it may be possible to better understand the material composition and orbit of asteroids that may hit Earth, which is crucial to finding ways to protect the Earth from asteroid impacts.
“Carbon-rich materials and hydrous clay minerals are just the tip of the universe’s iceberg,” said researcher Lauretta. When peering into the ancient secrets preserved in the dust and rocks of the asteroid Benu, we are opening a time capsule, tracing the origins of the solar system and unlocking the mysteries of the universe.