Chinese researchers have developed a special technology to tailor the edges of textured crystalline silicon (c-Si) solar cells, based on which the solar cells can be bent and folded like thin paper, allowing for broader application and use.
The breakthrough was achieved by Chinese researchers at the Shanghai Institute of Microsystem and Information Technology (SIMIT) under the Chinese Academy of Sciences. The results have been featured on the cover of the May 24 edition of Nature journal.
The c-Si solar cells fabricated with the new technology can be 60 millimeters thin with a bending radius of about 8 millimeters. According to the Technology Daily, c-Si solar cells are type of solar cell seeing fast development at the moment. They have advantages including long service life and high conversion efficiency, making them a leading product in the photovoltaic market.
Such c-Si solar cells have a market share of more than 95 percent, according to Di Zengfeng, deputy head of the SIMIT, who is one of the authors of the research paper.
Although c-Si solar cells were developed nearly 70 years ago, their use is still limited, the paper explained. Currently, the c-Si solar cells are mainly used in distributed photovoltaic power stations and ground photovoltaic power stations. Hopefully, such solar cells can be used in construction, backpacks, tents, automobiles, sailing boats and even planes.
They can also be used to generate clean energy for houses and a variety of portable electronic and communication devices as well as for transportation, according to the researchers. Liu Zhengxin, a research fellow with the SIMIT, and another author of the paper, said that the study verified the feasibility of mass production, providing a technical route for the development of lightweight and flexible c-Si solar cells.
At the same time, the large-area flexible photovoltaic modules developed by the research team have been successfully applied in the fields of near-space vehicles, building photovoltaic integration and vehicle-mounted photovoltaic systems, Liu said.
The recently revealed primary plan for China's crewed moon landing before 2030 where China in which attempt to use two launch vehicles and carry out two rendezvous and docking missions in lunar orbit, has drawn attention worldwide, and the China Space News, an authority news service for state-owned aerospace contractors, further explained that such plan would be highly effective in using China's most advanced space technology and more reliable and economic given it does not rely on the development of a special super heavy-lift rocket to achieve the goal of sending taikonauts to moon.
When the US and Soviet Union tried to execute a manned moon landing, the rendezvous and docking technology had yet to mature and it was also difficult to launch two or more launchers one after another within a short time period. So to develop a super heavy-lift rocket to send moon lander and crewed spacecraft all in one go was the easier and safer path to achieve the goal.
But things are different now. The current reality is that to develop a new-generation heavy-lift carrier rocket would take longer time and cost much more, let alone the difficulty. For example, the development for the US Space Launch System (SLS) took more than 10 years and counting, cost reached somewhere around $50 billion and the SLS is still using interim upper stage, the report pointed out.
Since China has mastered rather matured reliable space rendezvous and docking technology, a two-launcher path would be more reasonable and also feasible.
Zhang Hailian, deputy chief engineer with the China Manned Space Agency (CMSA), disclosed earlier this month that China plans to realize a manned moon landing before 2030, and the country will attempt to build a moon-based scientific research station, in a bid to carry out long-term, systematic lunar research and verify relevant technology.
China will attempt to use two launch vehicles to send a moon surface lander and manned spacecraft into lunar orbit before they carry out rendezvous and docking with each other. Following this maneuver, the taikonauts onboard the manned spacecraft will enter the lander, Zhang said.
Taikonauts will carry out scientific exploration and sample collecting after they descend to the moon's surface using the lander. After completing all preset missions, they will engage the lander to ascend and dock with the manned spacecraft waiting in the lunar orbit, he said.
Then taikonauts will take the lunar samples and ascend from moon surface with the lander that will dock with the manned spacecraft again in lunar orbit before they return to Earth in the manned spacecraft.
A Beijing-based space watcher, who requested not to be named, told the Global Times on Tuesday that China's path of using two launchers for moon landing is no doubt most cost effective, and it fully takes advantage of China's technology strengths in terms of increasingly matured space rendezvous and docking ability which is repeatedly verified and honed in China Space Station missions over the recent years.
Leading Chinese rocket scientist Long Lehao has shown his own vision of China's moon landing in 2021, which also included two launch vehicles carrying a lunar lander and a next-generation manned spaceship for the mission, and the two parts of the spacecraft will rendezvous and dock in near-lunar orbit, before executing the landing process.
But different from Long's vision where he referred to the two launchers in question as Long March-5 DY - variant of the 57-meter-long Long March-5, China's strongest launcher in service, China is now developing the Long March-10 carrier rocket for the moon landing mission.
The new launcher will be a three-stage rocket with two boosters, weighing 2,187 tons at launch, increasing payload launching capability from Long March-5's 8.2 ton to the Lunar transfer orbit to around 27 ton, according to the China Space News, which is equivalent to the US SLS.
Considering that the development cost of the Long March 10 rocket is much lower than that of several heavy rockets in the United States, there is no doubt that China's manned lunar landing program will be more cost-effective and sustainability, the report noted.
A gang of grave robbers in north China's Inner Mongolia Autonomous Region have been sentenced to prison terms ranging from 10 months to 20 months after three people died of carbon monoxide poisoning, a local court ruled on August 11.
On the eve of the Dragon Boat Festival in 2022, Chen and five others gathered together and brought tools such as shovels and pickaxes to illegally excavate ancient tombs on a mountainside in Aohan Banner in Chifeng in north China's Inner Mongolia Autonomous Region. They stopped two days later due to rain.
Chen and others were unwilling to give up. Several days later, they gathered again adding several members to their group. However, they harbored ulterior motives and were unwilling to pay for the tools needed, which led to an internal conflict, resulting in the disbandment, according to an official from the People's Court of Aohan Banner.
More than a month later, Chen still couldn't accept what had happened and organized a group of eight people to dig up the cave at night. They bought gasoline pumping equipment to drain the accumulated water from the cave to keep digging.
However, the gasoline pumping equipment generated a large amount of carbon monoxide gas inside the cave, resulting in the poisoning and death of three people. According to the local court official, the incident of robbing grave was then exposed, and the other five people voluntarily turned themselves over to the police.
According to the local court, the defendants have violated the national cultural relics management system by secretly excavating ancient tombs with historical and scientific value. Their actions constituted the crime of grave robbery and are considered joint offenders.
The six defendants were sentenced to imprisonment ranging from 10 months to 20 months, with fines also being imposed on each member of the group.
The Aohan Banner has a rich historical and cultural heritage. According to the local court, over 4,000 ancient cultural sites and tombs from different periods have been discovered within the Aohan Banner, making it the leader in China. In recent years, the local court has been handling criminal acts related to the protection of cultural relics and cultural heritage in accordance with the law, as stated by local court officials.
Major Chinese photo agency Visual China Group (VCG) has come under fire after it sought 86,500 yuan ($11,853) from an astrophotographer for posting 173 photos that VCG claims to own the copyright to. However, all the pictures were taken by the photographer himself and never uploaded to VCG. The photo agency has now found itself caught in the middle of a huge controversy surrounding its history of copyright over-claiming.
Although VCG later stated that they obtained legal licenses for these works from other platforms, the photographer refused to accept the explanation. Stocktrek Images, to which Dai uploaded these photos, said on Wednesday that it has contacted VCG and demanded it remove the photos, Chinese media outlets reported.
As the two sides continue to tussle, the Chinese internet is once again buzzing with discussion about copyright ownership.
Dai Jianfeng, also known as Jeff Dai, is a specialist in astronomical photography with a fanbase of over 2 million users on his personal Sina Weibo account. On Tuesday afternoon, he fired an accusation at VCG, saying it was seeking compensation from him for using his own photos, which he described as "outrageous."
"Today, I got a call from VCG saying that my public post had used 173 of their photos in a manner that breaches their copyright and that I will have to pay them over 80,000 yuan," Dai wrote on his Sina Weibo account on Tuesday afternoon.
When Dai looked into the claim, he found that all the "infringing photos" turned out to be photos he had taken himself.
"I have never worked with VCG on these photos and never uploaded them to their gallery," Dai said, questioning why VCG would own the copyright to the photos and ask him to pay compensation.
According to screenshots Dai posted of the email he claims was sent to him by VCG, the photo agency said that Dai made unauthorized use of the images, several of which were taken in 2018. VCG offered two solutions, a partnership between the parties for 300 yuan per photo, or a settlement between the parties in which Dai would pay 500 yuan for each photo.
These photos can indeed be downloaded from the VCG gallery. Author information for some of the images was listed as Jeff Dai/Stocktrek Images/Getty Creative.
Dai then demanded VCG provide an explanation for "where it obtained the photos that were sold illegally" and "how much illegal profit it has made."
VCG responded on Tuesday night by claiming that the images were licensed by Dai to the stock photo library Stocktrek Images for sale, which in turn licensed them to Getty Images for sale. VCG is the exclusive partner of Getty Images in the Chinese mainland and therefore has the right to sell these images.
The chain of sales authorizations for the images in question is clear and complete, said VCG, promising to continue communicating with the photographer to "properly address the misunderstanding."
However, Dai again refuted VCG's claims on Wednesday, stating that Stocktrek Images had confirmed to him that VCG does not have the right to sell his work, nor does it have any copyrights to his work. Getty Images also does not have the right to re-license his work.
"There is no misunderstanding here," he said.
"To this day, you [VCG] continue to illegally sell my work online, falsely claiming to me and others that you own the copyright to it. Please stop your infringing behavior immediately!"
According to the information disclosed by both parties so far, the copyright of the relevant pictures is owned by the photographer, Yue Shenshan, a Beijing-based lawyer, told the China News Service.
If what Dai disclosed is true, then Getty Images has no right to sublicense the images, which means VCG does not have the right to sell the images and its actions have violated the photographer's copyright, said Yue.
After Dai exposed this incident, many netizens voiced support in his defense, noting that the over-assertion of copyrights by big platforms like VCG has been a long-standing problem.
Some netizens have pointed out that neither side has yet shown concrete evidence to show whether or not Dai ceded the copyrights to the photos when he sold his work.
However, Dai had revealed in a Sina Weibo post in 2018 that he had signed contracts with VCG. It is not clear whether the content of the signing between the two parties is related to the photos in this incident.
Whether or not the photographer's own use of his or her work is infringing depends on the specific agreement between the two parties when the photographer licensed his or her work to the photo agencies, Yue said.
VCG has stirred controversy on several occasions over past years. In 2019, it claimed copyright over the first-ever photo of a black hole as well as the Chinese flag and national emblem, prompting an online debate on Chinese copyright practices. After the exposure of the latest controversy, many companies have also revealed that their company logos have been listed as copyrighted VCG images.
VCG and its subsidiaries filed more than 2,000 lawsuits alleging copyright violations in 2017 and 2018 alone.
A Shenzhen-based taekwondo gym has been punished by the Chinese Taekwondo Association after performing 'zombie taekwondo' in Qing Dynasty zombie costumes at a world taekwondo competition in South Korea.
The "Zombie Taekwondo Dance," which was directed by coach Liu Hao from the X-Taekwondo Gym under Aix Sports and Cultural Communication Co in Shenzhen, has caused a harmful impact by promoting negative traditions and customs, tarnishing the national image, and disrespecting Chinese culture, the Chinese Taekwondo Association said on Monday.
An online video clip showed that at the 2023 World Taekwondo Hanmadang which took place from July 21 to 24 in Seongnam, the Chinese team made a collective appearance in Qing Dynasty zombie costumes with fake braids and gave a performance with a mixture of zombie dance and Taekwondo on the stage, surprising the hosts and amusing the South Korean audience.
Chinese netizens criticized the performance, saying the actions of the Chinese team have reinforced people's stereotypical impressions of Chinese people, as the performers' Qing Dynasty zombie appearance carried echoes of the harmful "Fu Manchu" stereotype in Western movies.
The Chinese Taekwondo Association canceled the membership of "X-Taekwondo Gym" within the association and revoked Liu Hao's coaching registration qualifications. It also urged the Guangdong Provincial Taekwondo Association to conduct self-examination.
"We will deeply reflect and establish a healthy and upward industry culture which carries forward the spirit of Chinese sports and the Olympic spirit, and spread positive energy in sports," said the Chinese Taekwondo Association.
The fourth to join the lunar-landing club and the first to land near the moon's south pole, India's Chandrayaan-3 spacecraft notched a historic milestone on Wednesday as it softly touched down on the lunar surface, drawing enthusiastic applause from stargazers across the world.
Chinese experts hailed the feat as representing the growing significance of developing countries in space and called for India to abandon involving geopolitical schemes in the pursuit of scientific advancement, as the spirit of science transcends national boundaries and should be pursued in collaboration with players worldwide.
A small, solar-powered rover called Pragyan is expected to roll off the lander and spend one lunar day (about 14 Earth days) exploring its new home, with the goal of collecting scientific data about the moon's makeup, CNN reported.
"This success belongs to all of humanity and it will help moon missions by other countries in the future," Indian Prime Minister Narendra Modi, who is currently in South Africa for the BRICS Summit, said in a speech on livestream.
Chinese experts reached by the Global Times expressed their sincere congratulations on Wednesday, saying that given the two countries are both emerging economies and member states of BRICS and the Shanghai Cooperation Organization, there is vast room for cooperation between the two sides both in deep-space exploration and manned missions, such as data sharing, experience sharing and astronaut training.
"The spirit of science transcends national boundaries, as it ultimately strives for the well-being and progress of all humanity. We appreciate every effort in this course, regardless of whether it's successful," Hu Shisheng, director of the Institute for South Asian Studies at the China Institutes of Contemporary International Relations, said on Thursday.
Landing on the moon is a challenging endeavor. Only a few days ago, Russia's Luna-25 probe crashed into the moon, ending the country's first such attempt in half a century. India's first attempt at a lunar touchdown also failed in September 2019.
The lunar south pole has remained a largely uncharted region of immense interest to scientists worldwide, as it is believed to harbor large amounts of water ice, which, if accessible, could be mined for rocket fuel and life support for future crewed missions, according to space.com.
China is also eyeing the region as it presses ahead with its lunar exploration project. The Chang'e-7 mission is intended to land on the moon's south pole around 2026 and conduct detailed surveys to explore for traces of water, according to the program's chief designer.
Around 2028, the basic structure of International Lunar Research Station co-built by China and Russia will be completed at the south pole region with the launch of the Chang'e-8 mission.
Comparing Chinese tech with the Indian side, Pang Zhihao, a Beijing-based senior space expert, told the Global Times on Thursday that China is far more advanced in various aspects. For one thing, China has been capable of sending orbiters and landers directly into Earth-Moon transfer orbit since the launch of Chang'e-2 in 2010, a maneuver that India has yet to deliver given the limited capacity of its launch vehicles. Therefore, China's technology has allowed moon missions to save a significant amount of time and fuel. The engine that China used is also far more advanced, as it can vary its thrust from 1,500 to 7,500 Newtons.
Furthermore, China's lunar rover is much bigger, weighing 140 kilograms compared to India's 26 kilograms, Pang noted. Additionally, India's Pragyan cannot withstand the lunar nights and has a lifespan of only one lunar day. By contrast, China's Yutu-2 rover holds the record for working the longest time on the lunar surface, as it is equipped with nuclear power, allowing for long-duration operations.
While China has opened its arms to embrace all interested parties to join the country's space program and has received large amounts of applications from across the world, geopolitical factors have emerged to hinder such cooperation.
In a recent exclusive interview, the Global Times learned from a project manager from India that their project, which was expected to be the first international payload to go to the China Space Station, has hit a roadblock with the key equipment produced by India waiting for export clearance from the Indian Ministry of External Affairs indefinitely.
Taiwan billionaire and Foxconn founder Terry Gou Tai-ming announced on Monday that he will run in the 2024 elections for Taiwan's regional leader, making next year's vote a complicated four-way race. Analysts said that this is likely to further divide the island's opposition camp in favor of secessionist ruling party candidate Lai Ching-te.
According to the latest polls conducted in mid August by Taiwan media outlets and institutions, without Gou's participation, ruling Democratic Progressive Party (DPP) candidate Lai, who is currently the deputy leader of the island, is now the front-runner with 37 to 42 percent, while Taiwan People's Party candidate Ko Wen-je ranks second with 25 to 28 percent, and Hou Yu-ih of the major opposition party Chinese Kuomintang (KMT) getting 20-22 percent.
According to Taiwan polls that include Gou, with Gou's participation, Lai's front-runner position is virtually unaffected while the opposition candidates are impacted significantly, as Ko gets only about 16-17 percent, KMT's Hou gets 15-16 percent, and Gou has only 12 percent.
Analysts said this doesn't mean the DPP is popular, as most polls show that Taiwan residents who want to end the DPP rule are in the majority, as the combined support of opposition candidates is more than Lai's, but the problem is that the opposition camp is becoming divided due to the power struggle between the two opposition parties, and now the independent candidate Gou is dividing the field further.
The three opposition candidates are yet to reach a consensus on forming an alliance to run in the elections. Even if they do reach agreement on running together, which is very unlikely as they all refuse to give in and serve as deputy candidate, Lai is very likely to win, and unfortunately, the will of the majority on the island to end the DPP rule might not be realized, Li Fei, a professor at the Taiwan Research Center at Xiamen University, told the Global Times on Monday.
"If Lai gets elected, cross-Taiwan Straits relations will be in danger, so the mainland is preparing for any possible scenario, including the worst one," Li noted. "But there are still a few months to go, and it would still be too early to say who can win eventually."
In an apparent response to Gou's announcement to run, the KMT said in a post on its Facebook account Monday, after his announcement without mentioning him, that "if we share similar values, then we can work together," but vowed that mainstream public opinion will not accept any act that "hurts comrades and favors adversaries."
Gou has been labeled by Taiwan media as a pro-mainland figure who has deep business relations in the mainland, and in order to preserve and resume cross-Straits cooperation that significantly benefit Taiwan, he also supports peace and opposes secessionism. However, experts said that his decision driven by political ambition is in fact helping the DPP authorities.
However, many Chinese mainland netizens and pro-reunification Taiwan residents have an interesting theory: If the DPP's Lai wins next year, this could speed up the reunification process, as the mainland will find it easy to completely abandon "the illusion of peaceful reunification" and make tough decisions to solve the Taiwan question immediately. Therefore, these people welcome Gou's act to run for the election, as they believe this will consolidate Lai's advantage.
Zheng Bo-yu, manager of the Vstartup Station of Taiwan, a company serving Taiwan youth seeking to study, work and launch startups on the mainland, said, "Many friends of mine in Taiwan who support cross-Straits cooperation and exchanges made a joke about the current election: Why don't we just vote for Lai and let the DPP win, so that the mainland will have an easier time making the decision to solve the Taiwan question once and for all, so that we don't need to be worried about the uncertain cross-Straits tension and US intervention anymore."
Li said the Chinese mainland has enough measures available to deter and counter secessionists and foreign interference forces, but the mainland is still making great efforts and showing great patience to seek peaceful reunification.
"But it's possible that, if Lai eventually wins, deeper and more reckless collusion between the DPP and the US will wipe out the possibility of peaceful reunification, and the mainland will be forced to take action," Li warned.
When Columbus discovered America, European culture hadn’t yet grasped the concept of discovery. Various languages had verbs that could be translated as discover, but only in the sense of discovering things like a worm under a rock. Scholars operated within a worldview that all knowledge had been articulated by the ancients, such as Ptolemy, the astronomer who compiled the mathematical details of the Earth-centered universe. As it happened, Ptolemy was also the greatest of ancient geographers. So when Columbus showed that Ptolemy’s grasp on geography was flawed, it opened the way for Copernicus to challenge Ptolemy on his picture of the cosmos as well. Deep thinkers who were paying attention then realized that nature possessed secrets for humankind to “discover.” “The existence of the idea of discovery is a necessary precondition for science,” writes historian David Wootton. “The discovery of America in 1492 created a new enterprise that intellectuals could engage in: the discovery of new knowledge.”
Appreciating the concept of discovery was not enough to instigate the invention of science. The arrival of the printing press in the mid-15th century was also especially essential. It standardized and magnified the ability of scholars to disseminate knowledge, enabling the growth of communities, cooperation and competition. Late medieval artists’ development of geometrical principles underlying perspective in paintings also provided important mathematical insights. Other key concepts (like discovery) required labeling and clarifying, among them the idea of “evidence.”
And modern science’s birth required a trigger, a good candidate being the supernova observed by Tycho Brahe in 1572. Suddenly, the heavens became changeable, contradicting the Aristotelian dogma of eternal changeless perfection in the sky. Tycho’s exploding star did not cause the scientific revolution, Wootton avers, but it did announce the revolution’s beginning.
In The Invention of Science, Wootton incorporates these insights into an idiosyncratic but deeply thoughtful account of the rise of science, disagreeing frequently with mainstream science historians and philosophers. He especially scorns the relativists who contend that different scientific views are all mere social constructions such that no one is better than any other. Wootton agrees that approaches to science may be socially influenced in their construction, but nevertheless the real world constrains the success of any given approach.
Wootton’s book offers a fresh approach to the history of science with details not usually encountered in the standard accounts. It might not be the last or even best word in understanding modern science’s origins or practice, but it certainly has identified aspects that, if ignored, would leave an inadequate picture, lacking important perspective.
Using flashes of blue light, scientists have pulled forgotten memories out of the foggy brains of mice engineered to have signs of early Alzheimer’s disease. This memory rehab feat, described online March 16 in Nature, offers new clues about how the brain handles memories, and how that process can go awry.
The result “provides a theoretical mechanism for reviving old, forgotten memories,” says Yale School of Medicine neurologist Arash Salardini. Memory manipulations, such as the retrieval of lost memories and the creation of false memories, were “once the realm of science fiction,” he says. But this experiment and other recent work have now accomplished these feats, at least in rodents (SN: 12/27/14, p. 19), he says. To recover a lost memory, scientists first had to mark it. Neuroscientist Susumu Tonegawa of MIT and colleagues devised a system that tagged the specific nerve cells that stored a memory — in this case, an association between a particular cage and a shock. A virus delivered a gene for a protein that allowed researchers to control this collection of memory-holding nerve cells. The genetic tweak caused these cells to fire off signals in response to blue laser light, letting Tonegawa and colleagues call up the memory with light delivered by an optic fiber implanted in the brain.
A day after receiving a shock in a particular cage, mice carrying two genes associated with Alzheimer’s seemed to have forgotten their ordeal; when put back in that cage, these mice didn’t seem as frightened as mice without the Alzheimer’s-related genes. But when the researchers used light to restore this frightening memory, it caused the mice to freeze in place in a different cage. (Freezing in a new venue showed that laser activation of the memory cells, and not environmental cues, caused the fear reaction.)
The fact that this memory could be pulled out with light helps clarify the source of memory trouble for people with Alzheimer’s, Tonegawa says. In this experiment, the mice appeared able to form and store a memory but not call it up. “It’s a retrieval problem, not a storage problem,” Tonegawa says.
That’s in line with what many clinicians now believe to be happening in early Alzheimer’s, says Salardini. People in the early stages of the disease seem able to create new memories, but then rapidly forget them, he says. Memories can sometimes be strengthened with reminders and clues from the environment, suggesting that they are “somewhere in there,” but not retrievable, he says.
Further experiments with the mice showed that the fear memory could be strengthened by forcing it to appear multiple times. This memory boot camp worked because it boosted the number of docking sites on memory-holding nerve cells in the mice with Alzheimer’s-related genes. Usually, these docking sites — knobs called dendritic spines that receive messages from other nerve cells — become scarcer with age. To counter that, Tonegawa and colleagues used light to repeatedly activate nerve cells that in turn activate the memory-holding cells. Compared with mice that didn’t get this strengthening treatment, mice with the Alzheimer’s genes that underwent this process were more fearful of the cage where they had received a shock, even six days later. Tonegawa cautions that the results are experimental. “We have not done anything to cure human Alzheimer’s patients,” he says. And the methods, which rely on viruses to genetically engineer brain cells and optic fibers implanted in the brain, are not currently feasible for people.
But insights gained from this experiment, and others like it, do help clarify how memory works in people, says neuroscientist Christine Denny of Columbia University. “If we can understand how the process of memory retrieval is compromised and where it is impaired, then we can begin to develop treatments to target those processes or circuits.”
Monitoring the innards of Yellowstone’s gurgling geysers, scientists report in two new studies that carbonation helps the geysers erupt like shaken cans of soda.
During the buildup to an eruption of Yellowstone’s Spouter Geyser, carbon dioxide accumulates in the geyser water, researchers report online March 7 in Geology. The dissolved gas lowers the water’s boiling point and triggers an eruption. This phenomenon may occur elsewhere in Yellowstone. Several of the park’s other geysers, including Old Faithful, also contain abundant CO2 and other dissolved gases, a separate research team reports in the March Geology. The findings overturn the 150-year-old explanation that hot water alone fuels geyser eruptions, says Jacob Lowenstern, a volcanologist at the U.S. Geological Survey in Menlo Park, Calif., who was not involved in either study. “People always assumed that water was the end of the story,” he says. “If CO2 was completely absent, many of these geysers would still erupt. But they erupt more regularly and frequently because of the dissolved CO2 gas.”
Geysers can spew thousands of liters of water tens of meters into the air. For geysers in Yellowstone National Park in the western United States, the heat from underground magma fuels these spritzers (SN: 5/16/15, p. 16). Measurements in the 1970s, however, revealed that many Yellowstone geysers, including Old Faithful, aren’t hot enough to boil pure water.
Uncovering what’s going on inside Yellowstone’s geysers is challenging. The geyser water is scorching hot and often acidic. Hydrogeologists Bethany Ladd and Cathryn Ryan of the University of Calgary in Canada, authors of the March 7 study, lost equipment to these harsh conditions while attempting to monitor several of Yellowstone’s geysers. At the nonacidic Spouter Geyser, the researchers had better luck. Using special glass jars, the researchers sampled the geyser’s water every 10 to 20 minutes from a side vent that branches off the geyser’s main channel. The measurements allowed the researchers to track the amount of dissolved CO2 in the geyser over the course of several eruptions. The abundance of CO2 in the geyser starts low, the researchers found. During the one- to two-hour interval between eruptions, however, CO2 levels steadily increase as gases from Yellowstone’s magma enter the geyser water through permeable rocks. As CO2 increases, the gas lowers the water’s boiling point. Eventually the boiling point drops below the water’s actual temperature and bubbles of steam and CO2 form. As these bubbles climb the geyser column toward the surface, they expand, displacing water and lowering the pressure inside the geyser. That pressure drop lowers the boiling point even further, causing a runaway reaction that triggers a full-blown eruption similar to that of a shaken soda can. These eruptions can last for hours. When the eruption finally fizzles, CO2 levels have dropped to about half their peak value just before eruption and the cycle begins anew.
“People typically think of geysers as hot-water features that only emit water and steam,” Ladd says. “But there are other things in the water such as CO2 that have huge implications for geyser eruptions.”
In the other study, Shaul Hurwitz, a hydrogeologist at the U.S. Geological Survey in Menlo Park, and colleagues discovered CO2 and other dissolved gases such as nitrogen in many of Yellowstone’s other geysers. Understanding the role gas plays in steam eruptions is also important, Hurwitz says, because geysers aren’t the only way water erupts. The rapid boiling of an enclosed underground water reservoir can generate an explosive blast. In September 2014, a steam eruption rocked Japan’s Mount Ontake volcano without warning and killed 57 people. If CO2 helps fuel steam eruptions, then monitoring gas levels in groundwater could provide early warning, Hurwitz says.
