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China will study the use of artificial intelligence (AI) in avoiding space debris, a significant effort to use orbital resources more effectively and strengthen the control of super-large scale constellations, ensuring the safety of spacecraft in orbit and creating a new technology of rapid intelligent calculation capability for preventing large-scale space debris. 

The project on "intelligent modeling of the complex evolving principle of complex environments for space debris and autonomous monitoring" was launched by the State Key Laboratory of Astronautic Dynamics (ADL), affiliated with the Xi'an Satellite Control Center in Northwest China's Shaanxi Province. 

It was approved by the Ministry of Science and Technology as a "New Generation of Artificial Intelligence 2022 Major Program" in Science and Technology Innovation 2030, the Global Times learned from the satellite control center on Wednesday. 

Space debris generated by human activities has become a major obstacle and threat to space exploration. This situation urgently calls for joint efforts by the international community. 

According to researchers, there have been more than 640 events including explosions, disintegrations and collisions resulting in serious consequences during the history of astronautics.

There are more than 30,000 pieces of debris of more than 10 centimeters in space, more than 1 million with sizes ranging from 1-10 centimeters, and hundreds of millions that are just over 1 millimeter in size. 

Space debris research and monitoring face multiple challenges, including an extremely large number of pieces of passing debris at any one time. Difficulties in terms of fast computation and matching make it difficult to predict their speed, direction and fragmentation.

ADL has been engaged in researching space collision avoidance and space debris mitigation. Its new project aims to integrate AI model algorithms and domain knowledge.

"We will take the implementation of the project as an opportunity to actively align national strategic needs and cooperate with domestic competitive units to provide strong technical support for strengthening the nation's space traffic management and contributing to China's building of a space power," Li Hengnian, director of ADL, told the Global Times on Wednesday. 

"We will study the AI paradigm of online monitoring of space debris, the evolution of debris environment and space situational awareness," Jiang Yu, chief scientist of the project from ADL, told the Global Times on Wednesday. 

The China Space Station has successfully rolled out its first extravehicular radiation biology experimental payload outside Mengtian lab module, which is a device designed to study biological experiments under space exposure, and relevant tests have been carried out, the Global Times learned from the National Space Science Center (NSSC) under the Chinese Academy of Sciences on Thursday. 

It marked a first in the country's aerospace history to stage such biological experiments outside the spacecraft's cabin, which was hailed by Chinese scientists as a landmark event in the research and study of radiobiology and space science. 

According to Chinese experts, such a development also signified that the China Space Station, after entering its new development and application phase at the end of 2022, has increasingly tapped into its great potential in terms of space science, laying the ground for the country's future space exploration.

Such a radiobiology experiment device was jointly developed by the NSSC and the Dalian Maritime University. It will be mainly used to study the impact on model organisms of cosmic radiation and microgravity, and to study space radiation damage and protection, the origin and evolution of life, as well as space radiation. 

There are 13 sample boxes inside the device, which can be used to conduct in-orbit experiments on plant seeds, microorganisms and small animals. At the same time, each sample box unit can independently control the temperature to meet the survival needs of different sample organisms. Its cosmic radiation measurement includes both macroscopic radiation measurements and microscopic measurements of the sample.

The NSSC developers said that medical research based on such a device could play an important role in supporting taikonauts' long-term stay in orbit, future manned moon landing missions and other manned space projects. 

Pang Zhihao, a senior space expert, said that as there is no atmosphere on the moon, the cosmic radiation would have a big impact on taikonauts as well as their landing capsules. We can gather important data through space exposure experiments to make preparations in advance and to ensure the safety and health of our astronauts, said Pang. 

According to the NSSC, the device is in good working condition, meeting the demand for scientific studies. As the only space station extravehicular radiation biology experiment device, the device will carry out experimental work for a period of five years.

Space may look empty, but it contains extreme temperatures, high levels of background radiation, micrometeoroids and the unfiltered glare of the sun. Astronomers believe that there are ways to test the various components of space exposure individually on the ground, but the only way to get the combined effect of all of them at the same time is in orbit.

The International Space Station installed a similar platform codenamed MISSE to support space exposure experiments from 2001 to 2016, and updated this with a new one, the MISSE-EF in 2018, public records show. 

Huang Zhicheng, a senior expert on aerospace science and technology, told the Global Times on Thursday that China's space exposure biological experiments would focus more on human factors. That is to say, medical studies on astronauts' well-being when they are long exposed to cosmic radiation would be prioritized in the process. 

According to Huang, by doing so, China would accumulate valuable experience to support manned moon landings and even Mars landings in the future. "It will be a key technology development process to ensure taikonauts' health, especially for the long trip to Mars and back to Earth."

Huang said that the China Space Station has been serving as a platform to help improve the country's space technology, ranging from spacecraft technology to energy supply and life support systems. The time has come for it to make breakthrough in the more complicated space development and application fields. 

A total of 145 children from border regions and areas that receive aid met at the Three Gorges Dam in Central China's Hubei Province over the weekend during a themed summer camp to learn about the great achievement of the project.

The event aims to inspire students' sense of national pride, confidence, and the spirit of progress. As well as a field trip to the Three Gorges Dam in Yichang, Hubei, there are various activities such as visiting the Three Gorges Power Station, Three Gorges Project Museum, and the Yangtze River Rare Fish Breeding Center.

The majority of the participating students are from ethnic minority regions such as North China's Inner Mongolia Autonomous Region, Northwest China's Xinjiang Uygur Autonomous Region, and Southwest China's Xizang Autonomous Region. These areas are also designated areas for aid and support from the Three Gorges Group.

"I flew on a plane for the first time, and it was my first time on a ship. I'm so happy!" said Zubaiyier Maimaitijiang from Xinjiang's Bayingolin Mongolian Autonomous Prefecture. "The scenery of the Three Gorges is beautiful, and the Three Gorges Dam is magnificent!"

"This is the first time I have left my hometown to participate in an educational activity, and I've gained a lot. Seeing the majestic Three Gorges Dam makes me very happy," said Luobu Cuomu, from Dingqing county, Xizang.

Since 2006, nearly 10,000 outstanding students from primary and secondary schools in areas targeted for aid, as well as ethnic minority regions, have participated in this activity organized by the China Three Gorges Corporation, which can also contribute to the development of educational endeavors in these regions.

A fire broke out at a local inn in Liping county, Southwest China's Guizhou Province, on Friday, killing nine people and injuring two others. The injured were sent to the hospital immediately, and an investigation into the cause of the fire is underway, Liping emergency management bureau said on Friday.

The fire broke out at 1:02 am Friday and was put out around 1:35 am. Preliminary investigation found that the building is a brick-concrete structure, covering an area of about 240 square meters, according to the local emergency management bureau.

The inn is close to a local tourist attraction, with the room prices ranging from around 270 yuan ($37.09) to 400 yuan each room, according to media reports. Currently, it's not available for booking.

A tourist in another hotel said she was sleeping in the hotel when the power suddenly went out. She went to the balcony and saw flames from another inn a few hundred meters away. Fire trucks and ambulances passed through the hotel she lived in, and the crowd was noisy, the tourist said, according to Sichuan-based media The Cover. After the fire broke out, there was power outage in some inns in the scenic area, said the report.

Several local firefight authorities on Friday issued the news to remind tourists to be cautious, as homestay has become popular during recent years.

Zhaoxing Dong village, known as the "first village of Dong township," has over 1,000 households and nearly 6,000 residents. And it's also well-known for its five beautiful drum towers.

The Court of Final Appeal in the Hong Kong Special Administrative Region (HKSAR) on Tuesday dismissed the appeal of a former university student who had pleaded guilty to violating the National Security Law (NSL) for Hong Kong, which experts noted was an "instructive, authoritative, and binding" ruling that upholds the spirit of the rule of law.

Lui Sai-yu, who was a student from Hong Kong Polytechnic University, was sentenced to five years in prison in April 2022 by the district court in the HKSAR after being accused of "inciting others to commit secession." Lui didn't accept the decision and asked for an appeal. On November 30, 2022, the High Court of the HKSAR dismissed the appeal and upheld the sentence.

The district court in HKSAR had decided that the starting point for Lui's prison term should be five years and six months, then six months were deducted to reflect his guilty plea, RTHK reported on Tuesday. 

Normally a defendant who admits to his or her crimes receive a one-third reduction, but the six-month reduction was the maximum allowed under the NSL for Hong Kong, which specifies that those who commit a serious secession offense shall be required to serve a sentence of at least five years, but no more than 10 years, said the report.

During Tuesday's judgment, the judges refuted the appellant's argument that a five-year prison sentence should have been the starting point for sentencing - which would allow for actual sentences to be below the threshold, according to the report.

This case is of special significance in determining the legislative intent of the NSL for Hong Kong regarding the establishment of a mandatory minimum sentence. In fact, the appellate dispute of the case is whether the five-year minimum sentence for "serious cases" is a "sentencing guideline" or the "final sentence," Louis Chen, a member of the Election Committee and general secretary of the Hong Kong Legal Exchange Foundation, told the Global Times on Tuesday.

Article 33 of the NSL for Hong Kong clearly states that provisions related to lighter or reduced punishments do not include pleas of guilt; thus, defendants should not receive reduced sentences. Taking the crime of murder, which requires a mandatory life sentence, as an example, it emphasizes that mandatory punishments truly reflect the severity of the crime. The sentencing mechanism of the NSL for Hong Kong should prioritize deterrence, and not all mitigating factors apply, Chen said.

Willy Fu, a law professor and vice-chairman of the Hong Kong Legal Exchange Foundation, also welcomed and supported the ruling made by the court.

Fu pointed out that the NSL for Hong Kong is a national law and therefore holds a paramount position. The law needs to be coherent, compatible, and complementary with local laws. However, when inconsistencies arise between the NSL for Hong Kong and the local laws of the HKSAR, Article 62 of the NSL for Hong Kong should be given priority. 

This principle also applies to the interpretation of sentencing provisions in the NSL for Hong Kong. Therefore, local sentencing laws and principles fully function within the sentencing framework set by the law.

In the judgment released on Tuesday, the Court of Final Appeal in the HKSAR also correctly noted that "[local] sentencing laws must therefore operate in tandem with the NSL to achieve the aim of safeguarding national security, giving priority to NSL provisions in case of inconsistency." 

The law aims to prevent, stop, and punish crimes endangering national security. It should adhere to the rule of law, respect and safeguard human rights, combat the very small number of criminals endangering national security, protect the legitimate rights and interests of the majority of citizens, maintain HKSAR's prosperity and stability, and ensure the steady and far-reaching practice of One Country, Two Systems, Fu said. 

The court's ruling on the mandatory sentencing guidelines for the crime of secession under the NSL for Hong Kong, specifically regarding cases of "serious circumstances," which require a prison sentence of five to 10 years, clearly indicates that mandatory punishments reflect the severity of the crime. 

"This ruling is instructive, authoritative, and binding, upholding the spirit of the rule of law. Its significance is profound and deserves the support of the general public," Fu said. 

The National Nuclear Safety Administration (NNSA) has urged China's newly-built and projected nuclear power plants to fully consider water intake issues, in a bid to ensure the safe operation of nuclear power facilities.

During a recent meeting, the administration emphasized that relevant departments should improve water intake procedures due to changes in climate and sea environment over the years, to further ensure the smooth operation of nuclear power plants. This was stated by NNSA's official social media account on Monday.

The meeting was convened after Japan released nuclear-contaminated water from the crippled Fukushima Daiichi nuclear power plant into the ocean on Thursday. China halted aquatic product imports from Japan from that day and condemned Japan's actions as an irresponsible attitude towards the Chinese people and humanity as a whole.

The meeting underscored that the design of all newly-built and projected nuclear power plants should prioritize the security of water intake. Relevant hydrological, climatic, and marine biome data should be collected and monitored, and then utilized in professional research to address potential challenges in the sector.

Ice removal may soon become a lot easier. Researchers have developed a new method for making ice-phobic surfaces by altering the density and slipperiness of spray-on polymer coatings.

The process, reported online March 11 in Science Advances, could lead to a wide range of long-lasting ice-repellent products including windshields, airplane wings, power cables and frozen food packaging, researchers say.

Scientists know that ice easily detaches from softer, less dense materials. Further adjusting the density of rubber polymers used to make the coatings and adding silicone or other lubricants such as vegetable oil, cod-liver oil and safflower oil amplifies the effect, Anish Tuteja, a materials science engineer at the University of Michigan in Ann Arbor, and colleagues found.
In multiple laboratory and field tests, ice slid off treated surfaces under its own weight or when it was pushed by mild wind. The researchers further tested the coatings’ durability on various surfaces such as metal license plates and glass panes. The coatings performed well through two Michigan winters and retained their ice-repelling properties after controlled exposure to icing and heat cycles, corrosive substances such as hydrochloric acid, and wear and tear.

The process has already yielded more than 100 different coatings tailored for specific surfaces, including metal, glass, wood, plastic and cardboard. Tuteja says his team is working on licensing the materials for commercial use.

BALTIMORE — When it comes to swimming sperm, it’s not every man for himself. Instead, sperm form groups that swim together, a bit like schools of fish or flocks of birds, physicists have observed.

Understanding the physics underlying such behavior in animals is difficult because their actions arise in part from cognitive processes — birds, for instance, can see what their neighbors are doing and adjust their flight path accordingly. But with sperm, group swimming emerges from the physics of the medium in which they swim, Chih-Kuan Tung of North Carolina A&T State University in Greensboro said in a news conference March 16 at a meeting of the American Physical Society. That makes sperm a simpler system for studying the physics behind a form of coordinated biological action. “They don’t think,” Tung said. “So whatever interaction is happening, we can quantitatively describe it.”

Sperm don’t form groups in ordinary water, Tung said, but they do in viscoelastic fluids such as the mucus of mammalian reproductive tracts. A viscoelastic fluid combines resistance to flow with the ability to restore its previous state when disturbed. Tung and colleagues created such elasticity by adding a polymer to the fluid used for testing the swimming ability of bulls’ sperm. Those experiments showed that it’s the elasticity, not the viscosity, that encourages collective swimming.

Further work will be needed, Tung said, to determine whether such group swimming confers an advantage to sperm seeking an egg. In any event, the new understanding of sperm dynamics could lead to improved methods for in vitro fertilization procedures, he said.

There’s still enough forest left — if protected wisely — to meet the goal of doubling the number of wild tigers (Panthera tigris) by 2022, says an international research team.

That ambitious target, set by a summit of 13 tiger-range nations in 2010, aims to reverse the species’ alarming plunge toward extinction. Forest loss, poaching and dwindling prey have driven tiger numbers below 3,500 individuals.

The existing forest habitat could sustain the doubling if, for instance, safe-travel corridors connect forest patches, according to researchers monitoring forest loss with free, anybody-can-use-’em Web tools. Previously, habitat monitoring was piecemeal, in part because satellite imagery could be expensive and required special expertise, says Anup Joshi of the University of Minnesota in St. Paul. But Google Earth Engine and Global Forest Watch provide faster, easier, more consistent ways to keep an eye out for habitat losses as small as 30 meters by 30 meters (the space revealed in a pixel).
Looking at 14 years of data, 76 major tiger landscapes altogether have lost less than 8 percent of forest, the researchers say April 1 in Science Advances. Finding so little loss is “remarkable and unexpected,” they write. But 10 of those landscapes account for most of the losses — highlighting the challenges conservationists, and tigers, face.

Scientists may have found the cosmic birthplace of an ultra-high energy neutrino. They point the finger at a blazar — a brilliantly luminous galaxy that shoots a jet of radiation in the direction of Earth — 9 billion light years away.

If the link between the blazar and neutrino is real, scientists would be closer to long-sought answers about where such power-packing particles come from. Violent astronomical accelerators boost some neutrinos to high energies, but scientists have never been able to convincingly identify their sources.
Neutrinos are aloof elementary particles that rarely interact with other matter — they can sail straight through the Earth, and trillions of them zip through your body every second without a trace. On December 4, 2012, the neutrino in question (which scientists have affectionately nicknamed Big Bird) slammed into the Antarctic ice with an energy of around 2 million billion electron volts. The neutrino observatory IceCube glimpsed the aftermath of the collision and measured its energy with sensitive detectors embedded deep in the ice (SN Online: 04/07/14), leaving scientists hustling to pinpoint its source.

The blazar flared up at just the right time and place to be a prime suspect, researchers report in a paper accepted for publication in a peer-reviewed journal. The result, now available online at arXiv.org, strengthens the case that blazars are the source of such high-energy neutrinos, but it is no smoking gun.

After the neutrino was detected, a team of astrophysicists scoured the heavens for energetic galaxies with TANAMI, short for Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry, a network of telescopes peering into space at a variety of wavelengths. That team reported one likely candidate blazar.

But the candidate is not a surefire match, says IceCube leader Francis Halzen of the University of Wisconsin–Madison, who was not involved with the analysis. IceCube could determine the neutrino’s direction within only about 15 degrees on the sky, and the blazar flare-up continued for several months. The probability of such a chance concurrence between an unrelated neutrino and blazar is about 5 percent, the researchers say — too big to rule out chance. “It’s a very intriguing result,” says Halzen “but it’s not a proof.”

The matchup between the blazar and neutrino is noteworthy, even though the researchers can’t fully rule out the possibility that the match is a fluke, says astrophysicist Xiang-Yu Wang of Nanjing University in China, who was not involved with the research. “Given that the two events are very unique … I think it’s convincing.” Wang and colleagues have expanded on the result: In a paper accepted for publication in Physical Review Letters, they use the difference in arrival time between the neutrino and light from the blazar’s outburst — assuming the two are related — to test Einstein’s special and general theories of relativity. Certain theories of quantum gravity predict a delay in the arrival of a neutrino. (Einstein came out unscathed.)
The authors of the blazar study declined to comment on the result, citing the embargo policy of the journal where the paper will be published.

To convincingly identify a blazar as the source of a neutrino, Halzen says, scientists will need a better measurement of the neutrino’s direction, connected to a short-lived blazar outburst. In the future, Halzen says, IceCube will send out “astronomical telegrams” when it detects a neutrino, directing telescopes to take a look, perhaps catching a blazar in the act.