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In late September, 2023, NASA's OSIRIS-REx mission（任务）delivered bits of rock and dust collected from a distant asteroid（小行星）to Earth. The sample, from the asteroid named Bennu, is the first of its kind brought to the United States. Now, the public can see the asteroid's rocky debris（碎片）on display at the Smithsonian's National Museum of Natural History a few days ago.

Scientists think the 4.5-billion-year-old asteroid is composed of some of the solar system's oldest materials, formed in dying stars before the planets existed. Examining this ancient matter could hold clues about how organic materials first arrived on Earth, so NASA launched the OSIRIS-REx mission in 2016 to collect samples from Bennu's surface. The spacecraft arrived at the asteroid in 2018, surveyed the rock for an ideal collection site and ultimately took a sample back to Earth in 2020. Recently, an initial examination of the sample revealed evidence of a high carbon content and water on Bennu.

When the team was unpacking their sample, they found that "bonus" material from the asteroid covered the collector. The presence（存在）of this extra matter delayed NASA's processing of the sample. "The very best 'problem' to have is that there is so much material that it's taking longer than we expected to collect it," said Christopher Snead, the OSIRIS-REx deputy sample curator. Next, more of the material from Bennu will go on display at the museum. In the next two years, scientists will continue analyzing the sample and will save at least 70 percent of the Bennu rocks for further research.

NASA administrator Bill Nelson believes that studying Bennu samples will advance our understanding of the solar system for generations. It promises to shed light on(弄明白)what makes our planet unique. By studying this 4.5-billion-year-old sample and sharing it with the public, NASA aims to inspire future scientists and encourage them to explore new fields.

A lot of manufactured glass today made from sand and sodium carbonate （碳酸钠） can be reused or melted down and recycled into new items, but it doesn't break down in the environment and will sit in landfills for thousands  of years. A team of Chinese scientists aimed to deal with this environmental concern by developing an eco-conscious alternative.

In a study published recently in the journal Science Advances, a team at the Chinese  Academy of Sciences' Institute of Process Engineering describe how they engineered biodegradable glass made from amino acids(氨基酸). That glass would have a smaller impact on the environment and can break down in a few weeks or in several months.

In a test, glass beads (玻璃珠)made out of amino acids were placed under the skin of mice, and the breakdown of the bead and the skin healing process were observed for 30 days. A diagram from the study shows how the mice's bodies broke down the beads. In that month, the glass implant degraded beneath the skin, the wound site healed, and fur grew back. "Throughout the experimental period, no mice exhibited any pain-related behavior that may have been caused by the glass implantation, and none of them experienced obvious weight loss," the researchers wrote in their paper.

Although amino acids do degrade over time in the environment, this biodegradable glass is not as durable as traditional glass, because amino acids can break down quickly in heat. In order to overcome this hurdle, the researchers chemically modified the amino acids using the heating-cooling procedure applied in glass manufacturing. This is when materials for the glass are heated to become soft and then rapidly cooled so as to make the glass tougher.

"It's important to point out that this biodegradable glass is currently in the lab stage, and far from large- scale commercialization," emphasized Yan Xuehai, a professor involved in the study, in a press release.

Zhou Dongyu was born into an ordinary family in Shijiazhuang City, Hebei Province in early 1992. In 2010, Zhang Yimou chose Zhou from more than 8,000 actresses to star in Under the Hauthorn Tree, and she soon became known to the people of her hometown after winning Best Actress at the 56th Valladolid International Film Festival in Spain, the Outstanding New Actress Award at the 14th China Huabiao Awards and Best New Performer at the 20th Shanghai Film Critics Association Awards for her role in Under the Hauthorn Tree.

The luck of the young actress continued from there. In 2011, she was admitted to the Beijing Film Academy (BFA), China's most respected film school.

In the three years there, Zhou received a number of film offers and starred in several, but the characters always seemed the same. "I'm always that innocent girl—the first-love type," she once lamented. She felt the need to break out of the pigeonhole(禁锢). In 2013, Zhou auditioned(试演) for a small role in Breakup Buddies. "Actually, the director turned me down at first. But days later, he called me in for an audition. ‘I have to land this role' was all I could think on the way to the audition. It was the perfect opportunity to change my image." During her audition, Zhou was asked to do some name-calling. Two days later, she was told that she had been cast as a rural hairdresser, turning her previous lovable, innocent image upside down and resulting in the most memorable female character in the film.

After Breakup Buddies, Zhou began to receive a wider variety of offers, and she ended up playing an ill-tempered genius in The Ark of Mr. Chow and an agent in the TV drama Sparrow. "I still need to further improve my skills by playing different characters," says Zhou. "By doing this, I get a deeper understanding of a wider variety of people I might not have otherwise ever known."

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