Spacecraft components of China's Chang'e-6 lunar mission have arrived at Hainan Meilan International Airport aboard the An-124 and Y-20 transport aircraft successively on Monday and Tuesday before they were then transported by road to the Wenchang Space Launch Site, Global Times learned from the China National Space Administration (CNSA) on Wednesday.
According to the CNSA, the latest development marks a significant step for the fourth phase of the lunar exploration program, with pre-launch testing preparations underway.
The launch site facilities are currently in good condition, with all preparations progressing smoothly according to plan. Chang'e-6 is scheduled for launch in the first half of this year, said the CNSA.
The Chang'e-6 mission aims to break new ground in lunar retrograde orbit design and control, intelligent sampling on the moon's far side, and ascent from the lunar surface. It will conduct an automated sample return from the moon's far side, along with scientific exploration of the landing area and international collaboration, according to the CNSA.
Wu Weiren, chief designer of China's lunar exploration program, has previously revealed that Stage 4 Chang'e lunar probe missions - the Chang'e-6, -7 and -8 - will carry out new planetary exploration missions and further upgrade the country's space launch capabilities in the next 15 years.
According to Wu, who is also the chief scientist and director of China's Deep Space Exploration Laboratory (DSEL), the Chang'e-6, to be launched in the first half year of 2024, will attempt to achieve the world's first lunar sample return from the dark side of the moon.
The scale of such samples retrieved from the moon would be around 2,000 grams. The epic Chang'e-5 mission retrieved 1,731 grams.
To enhance international cooperation, Chang'e-6 will carry payloads and satellite projects from countries and institutes including France, the European Space Agency, Italy and Pakistan.
The Chang'e-7 mission, set for 2026, aims to land on the moon's south pole and carry out lunar resource and environment surveys in the area. Besides that, the Chang'e-8 will verify new technology that makes use of lunar resources.
Wu said that China plans to achieve a manned moon landing around 2030.
China's Wednesday update on its fruitful lunar probe series, Chang'e, named after the Moon Goddess in Chinese mythology, came within the same week that US private firm Astrobotic Technology said its NASA-backed spacecraft's attempt to be the first US lander to reach the moon in more than 50 years had "no chance" of touching down on the lunar surface due to an apparent issue with the vehicle's propulsion system.
NASA on Tuesday also announced that it was delaying the mission for US astronauts to travel to the moon by about one year. Artemis III, originally targeted for late 2025, is now set for September 2026, and even that time frame is "very aggressive," the agency said.
The film Snow Leopard, directed by China's late Tibetan writer-director Pema Tseden, won the Tokyo Grand Prix at the 36th Tokyo International Film Festival held from October 23 to November 1.
This movie was Pema Tseden's last film before his passing in May. Born in December 1969, Pema Tseden passed away this year due to an illness. Recognized as a pioneer of Tibetan-language films, the director created several famous works, including the 2018 film Jinpa and the 2019 film Balloon.
Pema Tseden was also an award-winning novelist, whose work has been translated into English, French, German, Japanese and Czech. He was a professor at the China Academy of Art in Hangzhou, East China's Zhejiang Province, and a member of the China Film Directors' Guild as well.
Described as a family drama, Snow Leopard was Pema Tseden's eighth Tibetan-language film. The film explores the close association between humans and animals through a story in which a snow leopard kills nine of a sheepherder's flock. It delves into the differing perspectives of various individuals regarding whether to release the snow leopard after it gets trapped in the sheep pen.
It took about three years to make the film, which was shot at the scenic Donggi Cona Lake in Madoi county in Northwest China's Qinghai Province. The name of the lake means "lake surrounded by a thousand mountains" in the Tibetan language. The area is also a habitat for snow leopards and many other endangered species.
Jigme Trinley, Pema Tseden's son and assistant director on Snow Leopard, said that his father's works have always told stories of the culture and life of Tibetan people, and how modern civilization has been impacting and integrating into their lives and thinking, media reported.
Snow Leopard was considered a significant breakthrough in Pema Tseden's filmmaking journey, embodying his new understanding of life, the world, and Tibetan culture, Jigme Trinley added.
The Israel-Gaza conflict entered its fourth day with Israel declaring on Tuesday control regained over the Gaza border. Chinese analysts urged US and Western leaders to stop the long-term marginalization of the Palestine issue or fan the flames of the conflict, calling for more efforts to calm the situation in order to prevent a potential sixth war in the Middle East.
In retaliation for the Hamas militant attack on Saturday, Israeli airplanes bombarded Gaza City's downtown nonstop until early Tuesday, cutting off the Gaza Strip from food and other supplies. According to Reuters, the Israeli military activated an unprecedented 300,000 reserve soldiers and placed a blockade on the Gaza Strip, increasing concerns that it was preparing a ground invasion in response to the most daring and deadliest Hamas offensive in decades.
As of press time on Tuesday, the cumulative death toll on both sides had risen to nearly 1,600. Gaza's Health Ministry on Monday said at least 687 Palestinians had been killed and 3,726 wounded in Israeli air strikes on the blockaded enclave, Reuters reported.
Early Tuesday, the leaders of France, Germany, Italy, the UK and the US released a joint statement in which they expressed their "steadfast and united support" to Israel and condemned the Hamas attack.
The Western leaders' acknowledgement of "the legitimate aspirations of the Palestinian people" was noted in the statement, but it has come under fire from netizens on social media for their double standards on the Palestine issue. Observers voiced concern that the US and certain Western leaders' biased support would worsen the conflict.
As long as Israel is seen as a member of their camp and Hamas as terrorists, the US and many European nations would want to offer Israel support in diplomacy and in rhetoric. However, if the conflict spreads, the scenario may get worse, Liu Zhongmin, a professor at the Middle East Studies Institute of Shanghai International Studies University, told the Global Times.
In an attempt to provide symbolic support to Israel and intimidate Iran and Lebanon's Hezbollah group, US made the one-sided decision to send weapons and warships to Israel.
However, since the US has been reducing its commitments in the region, it will not readily get back into the conflict, but to demonstrate its role, it may provide Israel with weaponry and intelligence, Liu said.
Although several EU leaders expressed support for Israel, considering the widespread sympathy for the Palestinians in European nations, the bloc may not accept long-term one-sided support for Israel, according to the expert.
For example, divisions among EU member states and a lack of convergence from EU institutions were on display on Monday over plans to halt aid to Palestine in response to Saturday's attack on Israel by Hamas. According to European media, several countries, including Ireland, Luxembourg and Denmark - had been pushing for the EU to call for de-escalation.
Concern over escalation
The international community is concerned about how the conflict will evolve. According to Liu, in order to reassure its citizens, the Israeli government would undoubtedly exact retribution on Hamas and undertake the heaviest strike it has ever launched. But it also faces another problem - Hamas is hard to eradicate from Gaza due to its close links to the local community, and if its use of force results in significant civilian casualties and humanitarian catastrophes in Gaza, it will come under greater moral pressure.
Liu noted that the risk of a sixth Middle East war still exists if Israel is engulfed by the desire for revenge and expands the war, or if Hamas finds itself fighting a last-ditch battle, or if more countries are dragged into the war.
"It would be a more pitiful situation if the war escalates with relevant parties losing their minds," said Liu.
There was no sign of cease fire on Tuesday. Hamas is ready to fight a long war with Israel, a senior member of the militant group was cited by the Associated Press as saying on Tuesday.
Moreover, the Lebanese armed group Hezbollah fired a barrage of rockets into Israel after at least three of its members were killed during an Israeli bombardment of Southern Lebanon amid soaring tensions on Israel's northern border, according to media reports.
The situation in Gaza is being closely watched by the international community. Sun Degang, director of the Center for Middle Eastern Studies at Fudan University said that the immediate priority is to stop additional parties from engaging in the Israel-Gaza conflict and from adding fuel to the fire. However, if Israel deploys significant ground forces into Gaza, the situation may become challenging with the possibility of an alarming humanitarian disaster.
As the situation worsened, the United Nations, foreign relief organizations, and public health professionals said they were increasingly worried about humanitarian needs in Palestinian regions. Approximately 6 percent of Gaza's population, or more than 137,000 individuals, are now taking refuge in facilities administered by the United Nations Relief and Works Agency for Palestine Refugees in the Near East, according to a statement made by UN Secretary-General António Guterres to reporters in New York.
China has paid high attention to the continued escalation of the Palestine-Israel conflict and urged all relevant parties to enact a cease fire. China is willing to maintain communication with all parties and make efforts toward stabilizing the Middle East, Chinese Foreign Ministry spokesperson Wang Wenbin said at a press conference on Tuesday.
The bloodshed and deaths in the Middle East once again bring to light the disastrous consequences of the US and Western countries' long-term marginalization of the Palestinian issue, analysts said. It also highlights that the US' strategy to promote normalization between Israel and the Arab states would be a castle in the air without resolving the Palestine issue.
Although there has been no official information from any relevant parties, there have been growing reports that a US-brokered deal to formalize diplomatic relations between Saudi Arabia and Israel may be victimized in the escalation of situation.
The Palestinian issue has historically been viewed by the global community as the most important, sensitive and fundamental problem in the Middle East. But in order to achieve reconciliation between Israel and Saudi Arabia and persuade more of its friends and other moderate nations to establish diplomatic ties with Israel, the US strives to sidestep or even ignore the Palestinian issue. Its goal is to put together a unified front to attack Syria and suppress Iran, Sun said.
The US should reflect its regional strategy and advocate for long-term solutions to Israel-Palestine conflict rather than stoking tensions, said Sun.
Palestine and Israel are neighbors that cannot be moved and the two-state solution is a concluding and right solution to solving the Palestinian issue. Without an independent country of the Palestinians, the security of Israel cannot be guaranteed, Sun said.
The brave resistance of China's ironclad friend, Serbia, against NATO during its aggression against former Yugoslavia in 1999, has touched many in China. The legendary achievement of the Serbian Air Force and Air Defense in shooting down a stealth fighter for the first time in human history won the respect of many Chinese people. In April, the news of Belgrade's purchase of FK-3 air defense systems from Beijing sparked discussions in the Western world. Serbian Deputy Prime Minister and Minister of Defense Milos Vucevic (Vucevic) shared his views on this and other hot button issues in a recent exclusive interview with Global Times reporters Hu Yuwei and Fan Wei (GT).
The defense minister expresses deep gratitude to China for its wholehearted support of Serbia's sovereignty and territorial integrity, and reaffirms its adherence to the one-China principle. He noted that Chinese weapons will help modernize the Serbian armed forces, and looks forward to the further development of bilateral cooperation, especially on the military front.
The senior official said that China, unlike other great powers, does not attach any conditions to its cooperation with Serbia, and has selflessly dedicated its achievements in various fields to attaining its global goals. He expressed optimism about that the tenacity of friendship between the two countries, and regarded China as one of Serbia's most reliable friends.
GT: The Chinese and Serbian people have a long-standing tradition of friendly relations. During the NATO aggression against former Yugoslavia in 1999, the Chinese people stood firmly with the Serbian people to defend Serbia's sovereignty and its right to safeguard its national unity. How do you view the efforts made by the Chinese people to support Serbia's national stability and sovereignty?
Vucevic: Overall, Serbia-China relations have been extremely close in recent years and are developing chiefly due to the excellent relations between the two presidents - Aleksandar Vucic and Xi Jinping. The traditional "ironclad friendship" is evidenced by the fact that in two years' time, the 70th anniversary of the establishment of diplomatic relations between our two countries will be marked.
We are deeply grateful for China's wholehearted support for the preservation of Serbia's sovereignty and territorial integrity, as well as for its ever-consistent and principled position on the Kosovo-Metohija issue. The mutual understanding between Serbia and China regarding sovereignty and territorial integrity suggests that we have an excellent relationship, which, I hope, will never change.
Serbia will never forget the support of the Chinese people who stood firmly with us during the defense against the 1999 NATO aggression that was immoral and unjust, launched without the consent of the United Nations Security Council, trampling on the fundamental principles of international law. Unfortunately, we also witnessed a terrible event in which the Chinese Embassy building in Belgrade was bombed and civilians who were doing their jobs lost their lives. A commemorative plaque was placed at that spot in memory of our deceased Chinese friends who, together with us, went through the ordeal of the bombing.
We are forever grateful to the Chinese people for everything they did for us during that tragic year of 1999, and for everything they continue to do, supporting us in everything so that our people and our country would persevere through challenging times.
GT: The Serbian military has purchased weapons and equipment developed by China, such as anti-aircraft missiles and drones. This is different from the choices made by other European countries, which mostly opt for American- or Russian-made equipment. Why did the Serbian military choose Chinese-made weapons and equipment, and what factors were considered in this decision?
Vucevic: Being a neutral country, Serbia cooperates with both its Eastern and Western partners, and has been committed to doing so for years. In the past, many assets have been delivered to Serbia, some of the most important ones undoubtedly being the Chinese FK-3 medium-range anti-aircraft missile system and the Chinese CH-95 and CH-92A UAVs.
The delivery of weapons and equipment from China has attracted public attention globally, but what is most important and what should be highlighted is that the Serbian Armed Forces are strengthening significantly thanks to the modern weapons and equipment, and are thus acquiring capabilities that they did not have before.
We will continue to enhance our capabilities, both in human resources and weapons and military equipment, in order to be able to protect our people, wherever they live, and in order to be the guarantor of Serbia's independence.
GT: What changes have Chinese weapons and equipment brought to the Serbian defense forces?
Vucevic: Equipping our armed forces with modern weapons and military equipment is excellent news for our military personnel, but also for our citizens. All decisions regarding the procurement of equipment for and modernization of our troops are based on thorough analyses and expert assessments carried out by the competent authorities of the Ministry of Defense and the Serbian Armed Forces. We are referring to modern weapons with which we strive to strengthen our defense capabilities and significantly improve our combat readiness. It is certain that the acquisition of the modern FK-3 anti-aircraft system has provided added security to our airspace and our country as a whole.
Furthermore, by acquiring the CH-95 remotely piloted aircraft from our Chinese partners, we have considerably improved our aerial reconnaissance and target engagement capabilities, which many countries in the region and the world do not have.
GT: We have noticed that the weapons and equipment provided by China to Serbia are mostly defensive in nature and primarily used for safeguarding the homeland. However, some Western media sources have taken the opportunity to hype up the claim that China's provision of weapons and equipment to Serbia has altered the regional military balance. What is your take on this view?
Vucevic: The Ministry of Defense and the Serbian Armed Forces are making great efforts to provide new and modernized weapons and military equipment intended for the defense of our country and our airspace.
Those who claim that the delivery of Chinese weapons has altered the regional military balance normally have no comment when it comes to our neighbors arming themselves with aircrafts, artillery-missile systems, armored vehicles, anti-armor systems, or drones whose purpose is the complete opposite of defense.
Serbia will continue to equip its military and enhance its defense capabilities in order to be able to address all security challenges, risks, and threats adequately, and preserve our people and our country.
GT: Some Western countries are now trying to contain China by exploiting the Taiwan question, similar to how they used the Kosovo and Metohija issue to pressure the Serbian government. What's your view on this?
Vucevic: We are truly grateful for China's wholehearted support for the preservation of Serbia's sovereignty and territorial integrity. China's position on the Kosovo-Metohija issue has always been principled and consistent, which is proof of the true friendship between the two countries.
In the same spirit, as the President of the Republic and Supreme Commander of the Serbian Armed Forces, Aleksandar Vucic, has repeatedly said, Serbia supports the one-China policy and condemns all attempts to threaten its unity. We strongly support the preservation of the territorial integrity and sovereignty of the People's Republic of China. For us, there is only one government with its seat in Beijing, and we view the island of Taiwan as an integral part of China.
GT: Some Western countries often smeared China as a "warlike" nation. However, in reality, China has always advocated for peaceful dialogue to resolve international disputes, including in its own reunification cause. How do you view China's stance, and do you think China will be an important force in maintaining world peace?
Vucevic: China has experienced major changes in a relatively short period of time. Its achievements have attracted global attention.
Unlike other great powers, China does not attach any conditions to its cooperation with Serbia, and has selflessly dedicated its achievements in various fields to attaining global goals.
We consider China our traditional and long-term friend in these challenging times, but also one of the crucial factors contributing to global peace and stability, which it has been proven countless times with China's peacetime policy and wise political moves.
GT: In the future, in which areas will the Serbian military deepen cooperation with the Chinese military?
Vucevic: I am glad to see that the last decade has seen an upward trend in military cooperation between Serbia and China. Friendly relations and mutual respect between the two Presidents, Aleksandar Vucic and Xi Jinping, have greatly facilitated and accelerated cooperation in all areas, especially in the field of defense.
Our cooperation in almost all areas of mutual interest has achieved great results. Regarding the bilateral Serbia-China relations, I would single out military to military cooperation, as well as economic cooperation and numerous investments, which are very important for our country.
As for our relations and cooperation in the future, I am extremely optimistic and I have confidence in the tenacity of our friendship. China is our strategic partner and one of Serbia's most reliable friends, so I am convinced that we will continue to develop our overall relations, especially in the fields of military-economic, military-medical, and military-educational cooperation.
Chinese state security authority on Friday revealed a case concerning espionage activities of the US Central Intelligence Agency (CIA).
According to a post of China's Ministry of State Security (MSS) on Friday, the MSS recently put a suspect surnamed Zeng, who was a staff member of a Chinese military industrial group and an important confidential employee, under enforcement measures after finding evidence that Zeng was conducting espionage activities.
Zeng, born in July 1971, was once sent by his company to study in Italy. During that period, an official of the US embassy in Italy, called Seth according to the post, took the initiative to get acquainted with Zeng. Since then, Seth gradually developed a close relationship with Zeng through activities such as dinner parties, outings, and operas.
Zeng gradually became psychologically dependent on Seth, and Seth took advantage of this to instill Western values into Zeng. Under Seth's solicitation, Zeng's political stance was shaken.
As the exchanges between the two gradually deepened, Seth revealed to Zeng that he was a member of the CIA's Rome station. Seth asked Zeng to provide sensitive information about the Chinese military to him, promising to pay a huge amount of remuneration and help Zeng's family to migrate to the US.
Zeng agreed and signed an espionage agreement with the US side and accepted the assessment and training from the US. After his studies abroad, Zeng returned to China and continued to meet secretly with CIA personnel many times, providing a large amount of China's core information to the US and collecting espionage funds from the CIA.
The MSS has transferred the case to the procuratorate for review and prosecution, according to the Friday post.
Northern Oklahoma is just as susceptible to a damaging earthquake within the next year as the most quake-prone areas of California. That’s because earthquakes are no longer just a natural hazard, the U.S. Geological Survey says. In its new quake hazards forecast released March 28, the agency for the first time has included artificially triggered seismicity.
An increased risk in the central United States largely stems from sites where fluids, such as wastewater from fracking, are injected underground (SN: 8/9/14, p. 13). Rising fluid pressure underground can unclamp faults and unleash earthquakes (SN: 7/11/15, p. 10). From 1973 to 2008, an average of 24 potentially damaging quakes rattled the central United States each year. From 2009 to 2015, an uptick in fracking activity helped skyrocket that number to 318 annual quakes on average, with a record-setting 1,010 tremors in 2015 alone. Around 7 million people currently live and work in central and eastern U.S. areas vulnerable to shakes stemming from earthquakes roughly above magnitude 2.7, USGS scientists estimate.
Human-caused quakes aren’t as powerful as their natural counterparts (the strongest induced quake in the United States clocked in at magnitude 5.6 in 2011 compared with the magnitude 7.8 San Francisco temblor in 1906, for instance). But the potential for more powerful shakes exists, the scientists warn. The new hazard assessment should help regulators revise building codes to better prepare for the rising risk.
The U.S. Environmental Protection Agency has a methane problem — and that could misinform the country’s carbon-cutting plans. Recent studies suggest that the agency’s reports fail to capture the full scope of U.S. methane emissions, including “super emitters” that contribute a disproportionate share of methane release. Those EPA reports influence the country’s actions to combat climate change and the regulation of methane-producing industries such as agriculture and natural gas production.
With EPA’s next annual methane report due to be published by April 15, early signs suggest that the agency is taking steps to fix the methane mismatch. A preliminary draft of the report revises the agency’s methane calculations for 2013 — the most recent year reported — upward by about 27 percent for the natural gas and petroleum sectors, a difference of about 2 million metric tons. Yet it’s unclear how that and other revisions will factor into final methane emission totals in the upcoming report. The draft estimates that U.S. methane emissions from all sources in 2014 were about 28 million metric tons, up slightly from the revised estimate for 2013 and well above the original 2013 estimate of 25.453 million metric tons. But the totals in the draft don’t include updates to emission estimates from the oil and gas industry. “EPA is reviewing the substantial body of new studies that have become available in the past year on the natural gas and petroleum sector,” says EPA spokesperson Enesta Jones. The agency is also gathering feedback from scientists and industry experts to further improve their reporting.
Methane, which makes up the bulk of natural gas, originates from natural sources, such as wetlands, as well as from human activities such as landfills, cattle ranches (SN: 11/28/15, p. 22) and the oil and gas industry. Globally, human activities release about 60 percent of the 600 million metric tons of methane emitted into the atmosphere each year. Once in the air, methane prevents some of Earth’s heat from escaping into space, causing a warming effect. Methane emissions currently account for about a quarter of human-caused global warming.
The EPA’s underestimation of U.S. methane emissions comes down to accounting. EPA samples emissions from known methane sources, such as cows or natural gas pipelines, and works out an average. That average is then multiplied by the nation’s number of cows, lengths of pipe and other methane sources. Results from this method disagree with satellite and land-based observations that measure changes in the total amount of methane in the air. A 2013 report in the Proceedings of the National Academy of Sciences found that U.S. methane emissions based on atmospheric measurements are about 50 percent larger than EPA estimates (SN Online: 11/25/13). EPA’s reports don’t just misjudge the scale of emissions, they also miss the long-term trend, recent work suggests. EPA reported that U.S. methane emissions remained largely unchanged from 2002 to 2014. But researchers report online March 2 in Geophysical Research Letters that emissions of the greenhouse gas rose more than 30 percent over that period. The United States could be responsible for as much as 30 to 60 percent of the global increase in methane emissions over the last decade, the study’s authors conclude. “We’re definitely not a small piece of that pie,” says Harvard University atmospheric scientist Alex Turner, who coauthored the study. Correctly tracking methane is important, Turner says, because over a 100-year period, the warming impact of methane is more than 25 times that of the same amount of CO2. Methane levels have also risen faster: Since the start of the industrial revolution, methane concentrations have more than doubled while CO2 has risen more than 40 percent.
While methane is more potent than CO2, there is about 200 times less methane in the atmosphere than CO2. Furthermore, methane stays in the atmosphere for only around 12 years before being absorbed by soil or breaking apart in chemical reactions. “If we reduce methane emissions, the climate responds very quickly and global warming would slow down almost immediately,” says Cornell University earth systems scientist Robert Howarth. “CO2, on the other hand, has an influence that will go hundreds to even thousands of years into the future.”
Turner and colleagues tracked methane across the continental United States using land stations that measure methane in the air and satellite observations that record dips in the infrared radiation frequencies absorbed and reemitted by methane. The researchers compared these methane measurements with those taken over Bermuda and the North Pacific Ocean — places upwind of the United States and far from major methane sources.
From 2002 through 2014, methane concentrations over the continental United States grew faster than those over the oceans, the researchers found. The difference was most pronounced over the central United States, where methane concentrations rose nearly twice as fast as in the rest of the country. Natural gas drilling and production boomed in in the central United States during the period studied, though the researchers could not precisely trace the source of the additional methane.
Turner and colleagues say they’re now working with EPA to reconcile the methane estimates. EPA will provide small-scale estimates of methane emissions down to a 10-kilometer-wide grid. By combining that grid with space and land observations, scientists should be able to isolate where methane mismatches are the most pronounced.
While Turner’s research can’t pinpoint the exact origins of the additional methane, other studies point to the oil and gas industry. The numbers that the EPA uses to tabulate methane emissions assume that equipment is functioning as intended, says Stanford University sustainability engineer Adam Brandt. Malfunctioning equipment can spew huge amounts of methane. That became abundantly – and visibly – clear last October when the largest U.S. methane leak in history began in an underground storage facility near Los Angeles. The leak released 97,100 metric tons of methane, equivalent to the annual greenhouse gas emissions of 572,000 cars, before being permanently sealed in February, researchers estimated in the March 18 Science.
Super methane emitters are a big problem elsewhere, too, albeit typically much smaller than the California leak, researchers report in the June 2016 Environmental Pollution. Surveying emissions from 100 natural gas leaks around Boston, the researchers found that 7 percent of leaks contributed half of the total methane released. In 2014, a different research team reported in Environmental Science & Technology that 19 percent of pneumatic controllers used at natural gas production sites accounted for 95 percent of all controller emissions.
Monitoring and quick repairs can stamp out rogue methane sources quickly, Brandt says. “This is a problem that’s easier to fix than it is to understand,” he says.
Most people do not marvel much at sand. We may enjoy how it feels under our bare feet, or get annoyed when someone tracks it into the house. But few of us see those quartz grains the way geologist Walter Alvarez does — as the product of 4.5 billion years of improbable cosmic and geologic events that defined the course of human history.
Sandy beaches exist because silicon — a relatively rare element in the solar system — happened to become concentrated on Earth during the solar system’s early days, Alvarez, of the University of California, Berkeley, writes in A Most Improbable Journey. While powerful solar particles swept lighter, gaseous elements toward the outer planets, more massive, mineral-forming elements such as silicon, magnesium and iron were left behind for Earth. Later on, in the molten crucibles between Earth’s colliding tectonic plates, these elements formed the raw materials for pivotal human inventions, including stone tools, glass and computer chips. The 4.5 billion years of history that led to a computer chip is just one of many stories of scientific happenstance that Alvarez presents. Best known for proposing that an asteroid impact killed off the dinosaurs, Alvarez argues that rare, unpredictable cosmic, geologic and biological events — what he calls “contingencies” — are key to understanding the human condition.
Fans of Bill Bryson’s A Short History of Nearly Everything will appreciate Alvarez’s enthusiastic, clearly written tour of contingencies that have shaped our world, starting with the origins of life on Earth. No matter how distant the event, Alvarez quickly zeroes in on its eventual impact on people: For instance, the formation of oceanic crust helped expose rich deposits of copper ore on Cyprus, later an epicenter of the Bronze Age. A catastrophic Ice Age flood formed the English Channel in which the Spanish Armada would later sink. And ancient rivers in North America smoothed the terrain of the westward trail for American pioneers in covered wagons.
Not all of Alvarez’s arguments are convincing — his claim in the final chapter that every individual is a “contingency” in his or her own right, given how many other people could have been born instead, feels more flattering than important. Still, it’s hard to argue with his observation that impulsive human actions can transform the planet just as much as earthquakes, asteroids and other difficult-to-predict, occasionally world-changing phenomena.
Critics of this macro view, described in academia as “Big History,” say that the approach sacrifices important nuance and detail. At roughly 200 pages of text, however, A Most Improbable Journey does not claim to be a comprehensive account of history or a replacement for more detailed, focused examinations of the past. Instead, it makes a compelling case for Big History as a fun, perspective-stretching exercise — a way to dust off familiar topics and make them sparkle.
WASHINGTON — It has been used by an assassin wielding a poisoned umbrella and sent in a suspicious letter to a president.
Ricin, the potent toxin and bioterrorism agent, has no antidote and can cause death within days. But a cocktail of antibodies could one day offer victims at least a slim window for treatment.
A new study presented February 7 at the American Society for Microbiology’s Biothreats meeting reveals a ricin antidote that, in mice, works even days after exposure to the toxin. Another presented study offers a potential explanation for how such an antidote might work. Doctors need some way to deal with ricin poisoning, said Patrick Cherubin, a cell biologist at the University of Central Florida in Orlando. Immunologist Nicholas Mantis agreed: “There is no specific treatment or therapy whatsoever.”
Though ricin has an innocuous origin (it’s found in castor beans), the poison is anything but harmless. It’s dangerous and relatively easy to spread — rated by the U.S. Centers for Disease Control and Prevention as a category B bioterrorism agent, just behind the highest-risk category A agents such as anthrax, plague and Ebola.
Ricin poisoning is rare but has featured in some high-profile cases. In 1978, Bulgarian writer Georgi Markov was hit in the thigh with a ricin-poisoned pellet shot from an umbrella gun. A few days later, he was dead. In 2013, a letter addressed to President Barack Obama tested positive for granules of the deadly toxin. A Texas woman had ordered castor bean seeds and lye online, for a do-it-yourself approach to making ricin. No one was injured.
Symptoms of ricin poisoning depend on how the toxin enters the body, and how much gets in. Inhaling ricin can make breathing so difficult the skin turns blue. Ingesting ricin can cause diarrhea, vomiting and seizures. Death can come as soon as 36 hours after exposure.
Ricin is known as an RIP — a scary-sounding acronym that stands for ribosome-inactivating protein, said Mantis, of the New York State Department of Health in Albany. In the cell, ribosomes serve as tiny protein factories. After ricin exposure, “the whole machinery comes to a screeching halt,” Mantis said. For cells, shutting down protein factories for too long is a death sentence. Scientists have developed two vaccines for ricin, though neither is available yet for use in humans. A vaccine may be “good for soldiers going into the field,” said biochemist Ohad Mazor of the Israel Institute for Biological Research in Ness Ziona. But unvaccinated people are out of luck. Mazor and colleagues developed a new treatment that could potentially help. The treatment is a mixture of three proteins called neutralizing antibodies; they grab onto ricin and don’t easily let go. With antibodies hanging onto its back, ricin has trouble slipping into cells and wreaking its usual havoc. Even 48 hours after inhaling ricin, roughly 73 percent of mice, 22 out of 30, treated with the antibodies survived, the team reported at the meeting and in a paper published in the March 1 Toxicon. Untreated mice died within a week.
Previous antibody treatments for ricin work well only if mice are treated within hours after exposure, Mazor said. For poisoned humans, that may not be long enough to diagnose the problem. Mazor doesn’t know how his antibodies might work in people, but he’d like to follow up his mouse work with studies in monkeys or pigs.
Scientists haven’t figured out exactly how antibodies help animals recover, but another study presented at the meeting offers a clue. Cherubin and colleagues added ricin to monkey cells in a dish, and then tracked how much protein was manufactured by the cells.
At high enough levels, ricin exposure shuttered the factories as expected. But when researchers stopped exposing cells to the toxin, protein synthesis started up again and cells recovered. “You need ongoing toxin delivery to eventually kill the cell,” Cherubin said. It’s possible that antibody treatments could cut off ricin delivery to cells, letting them bounce back from poisoning, said study coauthor Ken Teter, also a cell biologist at the University of Central Florida.
A strain of wild Hawaiian worms has helped unmask long-studied genes as just plain selfish. The scammers beat the usual odds of inheritance and spread extra fast by making mother worms poison some of their offspring.
Biologists have for decades discussed how two genes in the familiar lab nematode Caenorhabditis elegans might help embryos build their organs. Working with a little-studied wild strain, however, caused a rethink of the genes’ supposedly beneficial role “that flipped it on its head,” says UCLA geneticist Leonid Kruglyak. Instead of doing some body sculpting, the gene sup-35 doses the eggs with a toxin that will kill them after fertilization, two postdocs in the Kruglyak lab discovered. The toxin gene doesn’t poison itself out of the gene pool because it’s linked to a partner, pha-1, that lets embryos manufacture an antidote. Embryos die unless they inherit a copy of the antidote gene in either egg or sperm, and so the poison-antidote duo can spread unusually fast through populations.
Making a mom on occasion poison some of her offspring doesn’t benefit her but certainly helps the genes. Thus the long-known sup-35 and pha-1 form what’s called a selfish genetic element, Kruglyak’s team proposes May 11 in Science.
That analysis is “very clearly accurate,” says evolutionary geneticist Jack Werren of the University of Rochester in New York. The idea that a gene could behave selfishly, promoting its own spread regardless of its host’s interests, was once controversial (SN: 3/19/16, p. 12). But as molecular biology techniques have improved, researchers have found more and more examples. Many of the most dramatic forms of selfishness, the murderous cheats, come from bacteria, so Werren welcomes the C. elegans scam as a rare case discovered in animals. Kruglyak’s lab has described an earlier example in C. elegans: a gene that doses sperm with a toxin that kills embryos unless an antidote gene rescues them. Finding a second selfish element in the nematode, he says, suggests that these may not be as rare in animals as people have thought. The big community of researchers regularly studying C. elegans had missed discovering the selfish role for a simple reason: The main lab strain of nematodes carries the selfish element, explains study coauthor Eyal Ben-David. Whenever the standard strain mates or self-fertilizes (the species has both males and hermaphrodites), all the offspring inherit sup-35 and pha-1. Researchers see no weird die-offs.
In the Kruglyak lab, however, Ben-David and fellow postdoc Alejandro Burga were doing a project that required crossing the usual lab nematodes with the DL238 strain from Hawaii. In its natural state, this strain has somehow escaped invasion by the selfish sup-35/pha-1 pair.
A series of oddities in interbreeding the disparate strains pushed the researchers to reconsider the two genes. For instance, much higher percentages of offspring died in mixed-parent crosses than the routine few percent in same-strain pairings. And when Ben-David and Burga looked at the genes in the Hawaiian strain isolated from the wild, sup-35 and pha-1 just weren’t there.
That was a shock. Earlier experiments in the lab strain had shown that disabling pha-1 caused death in offspring — which it certainly does. The feeding tube of the dying embryos was not forming properly, so researchers at first speculated that the gene controlled tube development. Later work suggested a more nuanced role for it, Ben-David says, but the overall hypothesis remained that the genes helped regulate embryo development. The Hawaiian strain changed that thinking: “How is this wild isolate alive and happy without a gene that’s supposed to be essential for development?” Kruglyak wanted to know.
A better way of interpreting the old experiments, he and his colleagues suggest, is that the embryos died because pha-1 wasn’t providing the antidote to the sup-35 toxin. “No one had previously considered the possibility,” says David S. Fay of the University of Wyoming in Laramie, who has done much of the work exploring the role of these genes. “All the data, including a lot of our previous published and unpublished findings, seem to fit the [selfish gene] model perfectly,” he says. And perhaps the highest praise: “I wish we had somehow come up with the solution ourselves.”
