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World

Russia Says It Will Rejoin Ukraine Grain-Export Deal

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Russia said it would rejoin a deal allowing for the safe passage of Ukrainian grain, ending days of uncertainty over future shipments and feeding some criticism at home that Moscow had capitulated in the standoff.

Over the weekend, Russia suspended its involvement in an agreement with the United Nations and Turkey that was struck in July and allowed for the safe passage of grain exports from war-torn Ukrainian ports through the Black Sea to world markets. Russian authorities had said a maritime corridor used to facilitate the grain shipments had been used in an attack on Russia-occupied Crimea. Moscow threatened to board ships that left without its permission.

Russia’s Defense Ministry said early Wednesday it had received written guarantees from Kyiv that Ukraine wouldn’t use the corridor to attack Russian forces and that those were sufficient to rejoin the deal. President

Vladimir Putin

later Wednesday said that Russia reserved the right to pull out of the deal, but that it wouldn’t interfere in any future grain shipments from Ukraine directly to Turkey.

The justification provided by the Defense Ministry triggered derision in Moscow, where commentators have openly criticized Russia’s execution of the war in Ukraine. Senior military officials have at times drawn fire from pro-Kremlin military bloggers for losing ground to Ukraine’s army in recent months and for other moves these critics have called tactical or strategic mistakes. Russian officials have also had to defend themselves against criticism they have bungled a recent mobilization of reinforcements across the country.

“We trust Kyiv that the grain deal will not be used for military purposes. Brilliant,” wrote political commentator

Pavel Danilin,

director of the Center for Political Analysis, a pro-Kremlin Moscow-based think tank, questioning the logic of trusting Ukraine.

After Russia said over the weekend that it was suspending its participation in the deal, ships continued to pull in and out of Ukraine, navigating through a maritime corridor established to safeguard the trade. Moscow then threatened it would intercept ships that disembarked without permission, but Russia’s navy didn’t stop any vessels.

The relatively smooth operation, despite Russia’s suspension, was taken by some critics as a sign Moscow was powerless to upset the trade, even if it wanted to.

“The Kremlin itself simply fell into a trap from which it did not know how to get out,”

Tatiana Stanovaya,

founder of R.Politik, an independent political-analysis firm founded in Moscow, wrote on Telegram.

An oil refinery in Sicily, owned by Russia’s second largest oil and gas giant Lukoil, acts as a pass-through for Russian crude, which ultimately makes its way to the U.S. as gasoline and other refined oil products. Photo Illustration: Laura Kammermann

Among shipping and insurance executives, though, Russia’s suspension was threatening to dry up underwriting for voyages. Insurers were pulling policies and refusing to write new ones without Russia’s participation in the deal.

“You can’t get insurance with Russia out of the agreement,” said

Nikolas Tsakos,

president and chief executive of U.S.-listed, Greece-based Tsakos Energy Navigation Ltd. Shipowners said insurers have resumed offering cover.

The grain standoff came as Russia faces setbacks on the battlefield and far from it. Ukrainian forces have taken back swaths of terrain that Russian forces had occupied in the early days of the invasion. Meanwhile, Russia’s economic leverage over Europe, in the form of its once-prodigious sales of natural gas, has recently waned—at least temporarily. European buyers have pivoted from Russian supplies, while Moscow cut back sharply on its sales to Europe.

Still, the continent has managed in recent months to sock away enough gas in storage that analysts believe will help it avoid the sort of shortages and rationings many Western officials just a few months ago had been bracing to endure. That new comfort could be short-lived, analysts say, if there is a colder-than-expected winter or infrastructure problems that further disrupt supplies.

Russia’s grain-deal suspension threatened to increase economic pressure on Ukraine, which relied on agriculture for about 10% of its gross domestic product before the war, Western and Ukrainian officials said. The Russian shutdown also imperiled food supplies for millions of people in poorer countries that import Ukrainian wheat.

Russia’s invasion of Ukraine had bottled up those grain exports, sending global prices soaring. The U.N.-brokered deal moderated those prices, but also appeared to give Moscow outsize leverage on markets. As Mr. Putin threatened in recent weeks to leave the deal, Western officials accused him of using food as a weapon.

A U.N. official prepares to inspect in Istanbul a ship from Ukraine loaded with grain.



Photo:

yasin akgul/Agence France-Presse/Getty Images

Ismini Palla,

a spokeswoman for the U.N. at a coordination center in Istanbul that is charged with overseeing the deal, said Wednesday’s pause in shipping, which had been anticipated before Russia’s decision to rejoin the deal, was intended “to provide time for planning and discussions for the next movement of vessels.”

Ukraine shipped nearly 10 million tons of corn, wheat, sunflower oil and other products through the deal’s maritime corridor between August and October, helping to return the country’s exports to prewar levels. More than 100 large bulk ships are involved in the trade.

Russia stopped cooperating with the agreement after it accused Ukraine of using the corridor to attack Russian forces over the weekend. The U.N. said no military vessels are allowed to approach the corridor, which is closely monitored using satellite data.

In threatening to abandon the deal in recent months, Russia had complained that not enough of Ukraine’s grain was going to poor countries and said Western sanctions had slowed Russian food and fertilizer exports. U.S. and European Union officials say the sanctions don’t apply to food products. The U.N. said the measures have created obstacles to financing, insuring, shipping and paying for Russian products.

Russian shipping executives said vessel arrivals at Russian export ports had fallen by 20% over the past two months, with the majority of ships shifting to move Ukrainian cargoes.

U.N. Secretary-General

António Guterres

praised Russia’s renewed participation in the deal. Mr. Guterres “continues his engagement with all actors towards the renewal and full implementation of the Initiative, and he also remains committed to removing the remaining obstacles to the exports of Russian food and fertilizer,” his spokesman,

Stéphane Dujarric,

said.

Russia’s Defense Ministry said Wednesday that thanks to the U.N. and Turkey, “it was possible to obtain the necessary written guarantees from Ukraine” that it wouldn’t use the maritime corridor and Ukrainian ports for combat operations against Russia. Russia “considers that the guarantees received at the moment appear to be sufficient and resumes the implementation of the agreement,” it said.

Write to Jared Malsin at jared.malsin@wsj.com, Ann M. Simmons at ann.simmons@wsj.com and Costas Paris at costas.paris@wsj.com

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World

Zelenskiy demands firmer defence of Ukraine grains export corridor

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  • Turkish minister expects grains deal with Russia to continue
  • Russia attacks on Ukraine infrastructure cause power cuts
  • Civilian evacuations set from more areas of Kherson

KYIV/MYKOLAIV, Ukraine, Nov 2 (Reuters) – The world must respond firmly to any Russian attempts to disrupt Ukraine’s grain export corridor, President Volodymyr Zelenskiy said, as more ships were loading despite Moscow suspending its participation in a U.N.-brokered deal.

One of the global consequences of Russia’s war on its neighbour has been food shortages and a cost of living crisis in many countries, and a deal brokered by the United Nations and Turkey on July 22 had provided safe passage for vessels carrying grain and other fertiliser exports.

Russia withdrew from the accord over the weekend, saying it could not guarantee safety for civilian ships because of an attack on its Black Sea fleet.

In a late Tuesday night video address, Zelenskiy said ships were still moving out of Ukrainian ports with cargoes thanks to the work of Turkey and the United Nations.

“But a reliable and long-term defence is needed for the grain corridor,” Zelenskiy said.

“Russia must clearly be made aware that it will receive a tough response from the world to any steps to disrupt our food exports,” Zelenskiy said. “At issue here clearly are the lives of tens of millions of people.”

The grains deal aimed to help avert famine in poorer countries by injecting more wheat, sunflower oil and fertilizer into world markets and to ease a dramatic rise in prices. It targeted the pre-war level of 5 million metric tonnes exported from Ukraine each month.

The U.N. coordinator for grain and fertiliser exports under the accord said on Twitter on Tuesday that he expects loaded ships to leave Ukrainian ports on Thursday. Ukrainian Infrastructure Minister Oleksandr Kubrakov said on Twitter that eight vessels were expected to pass through the corridor on Thursday.

Having spoken to his Russian counterpart twice in as many days, Turkish Defence Minister Hulusi Akar hoped the deal would continue, adding that he expected a response from Russia “today and tomorrow”.

POWER CUTS

Russia fired missiles at Ukrainian cities including the capital Kyiv in what President Vladimir Putin called retaliation for an attack on Russia’s Black Sea Fleet over the weekend. Ukraine said it shot most of those missiles down, but some had hit power stations, knocking out electricity and water supplies.

Nine regions were experiencing power cuts.

“We will do everything we can to provide power and heat for the coming winter,” Zelenskiy said. “But we must understand that Russia will do everything it can to destroy normal life.”

[1/7] Commercial vessels including vessels which are part of Black Sea grain deal wait to pass the Bosphorus strait off the shores of Yenikapi during a misty morning in Istanbul, Turkey, October 31, 2022. REUTERS/Umit Bektas

The United States denounced the attacks, saying about 100 missiles had been fired on Monday and Tuesday targeting water and energy supplies.

“With temperatures dropping, these Russian attacks aimed at exacerbating human suffering are particularly heinous,” State Department spokesperson Ned Price told reporters at a daily briefing. Russia denies targeting civilians.

KHERSON EVACUATIONS

Russia told civilians on Tuesday to leave an area along the eastern bank of the Dnipro River in the Ukrainian province of Kherson, a major extension of an evacuation order that Kyiv says amounts to the forced depopulation of occupied territory.

Russia had previously ordered civilians out of a pocket it controls on the west bank of the river, where Ukrainian forces have been advancing for weeks with the aim of capturing the city of Kherson, the first city that Russian forces took control over after invading Ukraine on Feb. 24.

Russian-installed officials said on Tuesday they were extending that order to a 15-km (9-mile) buffer zone along the east bank too. Ukraine says the evacuations include forced deportations from occupied territory, a war crime.

The mouth of the Dnipro has become one of the most consequential frontlines in the war.

Seven towns on the east bank would be evacuated, comprising the main populated settlements along that stretch of the river, Vladimir Saldo, Russian-installed head of occupied Kherson province, said in a video message.

Russian-installed authorities in the Kherson region also said an obligatory evacuation of Kakhovka district, close to the Nova Kakhovka hydroelectric station, was to begin on Nov. 6.

Moscow has accused Kyiv of planning to use a so-called “dirty bomb” to spread radiation, or to blow up a dam to flood towns and villages in Kherson province. Kyiv says accusations it would use such tactics on its own territory are absurd, but that Russia might be planning such actions itself to blame Ukraine.

In the city of Bakhmut, a target of Russia’s armed forces in their slow advance through the eastern Donetsk region, some residents were refusing to leave as fighting intensified.

“Only the strongest stayed,” said Lyubov Kovalenko, a 65-year-old retiree. “Let’s put it this way, the poor ones. Everyone is wearing whatever clothing we have left.”

Rodion Miroshnik, “ambassador” of the neighbouring Russian-occupied region of Luhansk, said Russian troops and their allies had repelled Ukrainian attacks on the towns of Kreminna and Bilohorivka.

Moscow describes its actions in Ukraine as a “special military operations to demilitarise and “denazify” its neighbour. Ukraine and Western nations have dismissed this as a baseless pretext for invasion.

Reporting by Reuters bureaux; Writing by Grant McCool and Lincoln Feast; Editing by Simon Cameron-Moore

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World

Russia Moves to Pull Out of Ukraine Grain Deal After Blasts Hit Crimean Port

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Russia said Saturday that it would suspend participation in the export of agricultural products from Ukrainian ports, in response to an attack on the occupied Black Sea port of Sevastopol that it blamed on the government of Ukraine.

The Defense Ministry said in a statement published on Telegram that ships of the Black Sea Fleet and civilian ships involved in ensuring the security of the so-called grain corridor had come under attack. As a result, “the Russian side suspends participation in the implementation of agreements on the export of agricultural products from Ukrainian ports,” the statement said.

The move threatens to derail the United Nations brokered deal that unblocks Ukraine’s vital grain exports through the Black Sea, which is critical to addressing a global hunger crisis and comes a day after U.N. chief

António Guterres

urged Russia and Ukraine to renew the agreement, which is officially set to expire on Nov. 19.

Officials from Russia, Turkey, Ukraine and the U.N. signed the grain agreement in July, freeing millions of tons of food products that had been bottled up in the country since the Russian invasion began in February.

The agreement is one of the few diplomatic breakthroughs of the war and helped to bring the global price of wheat down to prewar levels, helping to ease a global hunger crisis that resulted in part from the conflict. Ukraine provided about 10% of the world’s wheat before Russia invaded.

If shipments of Ukrainian grain are halted, the suspension will likely drive up the global price of wheat, corn and other vital food products.

But Russia’s Foreign Ministry said that Ukraine’s armed forces used “the cover of a humanitarian corridor” to launch massive air and sea strikes and as a result Moscow “cannot guarantee the safety of civilian dry cargo ships participating in the Black Sea Initiative and suspends its implementation from today for an indefinite period.” It said appropriate instructions have been given to Russian representatives at the Joint Coordination Center in Istanbul, which controls the transportation of Ukrainian food.

A Turkish official said Turkey hasn’t been officially notified of Russia’s decision to suspend its participation in the deal. Turkish President Recep

Tayyip Erdogan

helped broker the deal.

Oleksandr Kubrakov,

Ukraine’s minister of infrastructure, said his country will continue supplying grains around the world. “The world should not be held hostage to Russia’s whims, hunger cannot be a weapon,” he said in a Tweet.

Russia’s decision to suspend it is also a major blow to Ukraine’s globally important agriculture industry, which returned to a nearly prewar level of grain exports earlier this month, largely due to the deal. Since the agreement was signed, Ukraine exported 9.2 million tons of food products through a safe corridor in the Black Sea, according to the United Nations.

Russian President

Vladimir Putin

has threatened to abandon the deal in recent months, arguing that not enough of Ukraine’s wheat was going to poorer nations and that not enough Russian food and fertilizers were being exported due to sanctions. Around one-quarter of the food shipped through the deal went to low-income countries, according to the U.N. Ukraine also has shipped wheat to crisis-stricken nations including Somalia, Afghanistan and Yemen under the agreement.

Stéphane Dujarric,

a spokesman for the U.N. secretary-general, on Saturday said, “We’ve seen the reports from the Russian Federation regarding the suspension of their participation in the Black Sea Grain Initiative following an attack on the Russian Black Sea Fleet. We are in touch with the Russian authorities on this matter.”

“It is vital that all parties refrain from any action that would imperil the Black Sea Grain Initiative which is a critical humanitarian effort that is clearly having a positive impact on access to food for millions of people around the world,” said Mr. Dujarric.

In Luch, a village near the Kherson front line, a resident plays with her dog in the basement where she has been living during the war.



Photo:

Virginie NGUYEN HOANG for the Wa

Volunteers distribute humanitarian aid in the village.



Photo:

Virginie NGUYEN HOANG for the Wa

When asked about how Russia’s decision would affect the operation of the grain corridor, a representative of the Joint Coordination Center referred to Mr. Dujarric’s statement.

Ukraine’s foreign minister said in a tweet, “We have warned of Russia’s plans to ruin the Black Sea Grain Initiative. Now Moscow uses a false pretext to block the grain corridor which ensures food security for millions of people. I call on all states to demand Russia to stop its hunger games and recommit to its obligations.”

A worker at a Ukrainian power plant repairs equipment damaged in a missile strike.



Photo:

sergei supinsky/Agence France-Presse/Getty Images

The remains of a house in the southern village of Luch, which has suffered frequent shelling.



Photo:

Virginie NGUYEN HOANG for the Wa

Ukraine President

Volodymyr Zelensky

accused Russia earlier this month of deliberately slowing the passage of vessels through the corridor, creating a backlog of more than 170 vessels waiting to transit. The corridor’s capacity is limited by the number of inspectors from Russia, Turkey, Ukraine and the U.N. who must check each ship as it enters and exits the Black Sea.

Russian Defense Ministry spokesman Lt. Gen. Igor Konashenkov said nine aerial drones and seven maritime drones were involved in Saturday’s attack. He said the air attacks were repelled, but a sea minesweeper, the Ivan Golubets, sustained minor damage, as did some defensive infrastructure in Yuzhnaya Bay, one of the harbor bays in Sevastopol.

“You could hear explosions coming in from the sea,” said Yevgeni Babalin, a dockworker at the Port of Sevastopol. “There are fears that the Admiral Makarov was hit by an underwater drone.They shot at it from the ship and from a helicopter.”

The Admiral Makarov, a frigate, replaced the Moskva as the Black Sea Fleet’s flagship after the latter was attacked earlier this year.

A broker in Odessa who arranges cargoes from Sevastopol to the Middle East said the situation at the port was tense with residents asked to stay inside by Russian authorities.

Mikhail Razvozhayev, the Russian-installed governor of Sevastopol, wrote on his Telegram messaging channel that the attack had caused minimal damage to civilian infrastructure but city services were put on alert. He appealed to residents of the city not to publicize videos or information of the attack that could aid Ukrainian forces “to understand how the defense of our city is built.”

Ukrainian officials haven’t claimed responsibility for previous blasts in Crimea, including a drone strike on the headquarters of the Black Sea Fleet in August, but rejoiced and vowed to reclaim the peninsula annexed by Russia in 2014.

Crimea has served as a rear base for Moscow’s military occupation of a swath of territory in southern Ukraine, where Kyiv’s forces are now seeking to dislodge Russian forces from part of the Kherson region.

Gen. Sergei Surovikin, the recently appointed commander of Russian troops in Ukraine, has acknowledged that the position in Kherson is challenging and that “difficult decisions” might be called for, without elaborating.

Russian-installed officials in Kherson began telling residents to leave the city earlier this month in what they said was preparation for a Ukrainian assault.

Kirill Stremousov,

deputy head of the Kherson region’s Russian-installed administration on Friday said the evacuation of civilians was complete.

Meanwhile, the Russian Defense Ministry spokesman accused the British Navy on Saturday of being responsible for sabotaging Nord Stream pipelines in late September. Western governments have found that explosions rocked Nord Stream and a parallel pair of pipelines, Nord Stream 2. Investigations are continuing. Some German officials have said they are working under the assumption that Russia was behind the blasts.

The U.K. Defense Ministry said in a tweet on Saturday: “To detract from their disastrous handling of the illegal invasion of Ukraine, the Russian Ministry of Defence is resorting to peddling false claims of an epic scale. This invented story, says more about arguments going on inside the Russian Government than it does about the west.”

—Alistair MacDonald and Costas Paris contributed to this article.

Write to Ann M. Simmons at ann.simmons@wsj.com, Jared Malsin at jared.malsin@wsj.com and Isabel Coles at isabel.coles@wsj.com

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US

Exclusive: Russia is prepared to quit Black Sea grains deal, writes to UN with demands

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GENEVA, Oct 13 (Reuters) – Moscow has submitted concerns to the United Nations about an agreement on Black Sea grain exports, and is prepared to reject renewing the deal next month unless its demands are addressed, Russia’s Geneva U.N. ambassador told Reuters on Thursday.

The agreement, brokered by the United Nations and Turkey in July, paved the way for Ukraine to resume grain exports from Black Sea ports that had been shut since Russia invaded. Moscow won guarantees for its own grain and fertiliser exports.

The agreement helped stave off a global food crisis: Russia and Ukraine are two of the world’s biggest grain exporters and Russia is the number one fertiliser exporter. But Moscow has repeatedly complained about its implementation, arguing it still faces difficulty selling fertiliser and food.

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In an interview with Reuters, Gennady Gatilov, Russia’s ambassador to the United Nations in Geneva, said Moscow had delivered a letter to U.N. Secretary-General Antonio Guterres on Wednesday setting out a list of complaints. U.N. officials are due in Moscow on Sunday to discuss the renewal of the agreement.

“If we see nothing is happening on the Russian side of the deal – export of Russian grains and fertilisers – then excuse us, we will have to look at it in a different way,” he said.

Asked if Russia might withhold support for the grains deal’s renewal over the concerns, he said: “There is a possibility…We are not against deliveries of grains but this deal should be equal, it should be fair and fairly implemented by all sides.”

Gatilov declined to make a copy of the letter available.

U.N. speokesperson Stephane Dujarric said: “We remain in constant touch with Russian officials, as well as with officials from the European Union, the United Kingdom and the United States in order to remove the last obstacles to facilitate the export of Russian grain and fertiliser.”

He said Guterres was committed to those efforts and to having an extended and expanded Black Sea Grain Initiative.

Gatilov, a career diplomat who was deputy minister of foreign affairs before taking up the Geneva post, said that he saw fading prospects for a negotiated settlement to the nearly eight month war in Ukraine. He cited what he called “terrorist acts” such as an explosion on a bridge to Crimea.

“All this makes it more difficult to reach a political solution,” he said.

Washington has said that Russian claims to be open to talks on the war’s future amount to “posturing” as it continues to strike Ukrainian cities. read more

Asked about the prospect of a meeting between President Vladimir Putin and U.S. President Joe Biden, Gatilov said it was not feasible given the levels of U.S. military support for Ukraine. “It makes the U.S. a part of the conflict,” he said.

However, he was more upbeat on other negotiated outcomes such as on aid access and a further prisoner swap, calling these “a possibility”. He said a delegation of the International Committee of the Red Cross had met with Russia’s defence ministry in Moscow recently about a possible swap, without giving further details. The ICRC did not immediately respond to a request for comment.

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Reporting by Emma Farge
Editing by Peter Graff

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Science

Grains of dust from asteroid Ryugu older than our solar system

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28Si hotspots. (f) 17O-rich presolar oxide found in the Ryugu A0058-2 matrix. (g)–(h) This O-anomalous presolar grain was found in the less altered area shown in (b). The inlet in (g) shows a δ18O sigma image in which every pixel represents the number of standard deviations from the average values. The grain is probably a presolar silicate as Si is present in the EDX map, and Al was neither detected in the EDX map nor the NanoSIMS ion image, unlike the adjacent spinel (MgAl2O4), purple in color in (h). Credit: The Astrophysical Journal Letters (2022). DOI: 10.3847/2041-8213/ac83bd”>
28Si hotspots. (f) 17O-rich presolar oxide found in the Ryugu A0058-2 matrix. (g)–(h) This O-anomalous presolar grain was found in the less altered area shown in (b). The inlet in (g) shows a δ18O sigma image in which every pixel represents the number of standard deviations from the average values. The grain is probably a presolar silicate as Si is present in the EDX map, and Al was neither detected in the EDX map nor the NanoSIMS ion image, unlike the adjacent spinel (MgAl2O4), purple in color in (h). Credit: The Astrophysical Journal Letters (2022). DOI: 10.3847/2041-8213/ac83bd” width=”800″ height=”530″/>
(a) Backscattered electron (BSE) image of Ryugu thin section A0058-2. Every black area consists of ∼20 NanoSIMS maps measured. (b) An area in section C0002 with a less altered lithology than the surrounding Ryugu matrix (“clast 1”; BSE image). This area contains Mg-rich olivine, low-Ca pyroxenes, and spinel grains with sizes up to ∼15 μm (Kawasaki et al. 2022). Two of three O-anomalous grains identified in Ryugu, including one likely presolar silicate (g)–(h), were found in this region. (c)–(e) Secondary electron (SE) image of a Ryugu particle pressed into gold foil in which two presolar SiC grains were detected. The C-anomalous regions, indicated by the white arrows, are clearly associated with 28Si hotspots. (f) 17O-rich presolar oxide found in the Ryugu A0058-2 matrix. (g)–(h) This O-anomalous presolar grain was found in the less altered area shown in (b). The inlet in (g) shows a δ18O sigma image in which every pixel represents the number of standard deviations from the average values. The grain is probably a presolar silicate as Si is present in the EDX map, and Al was neither detected in the EDX map nor the NanoSIMS ion image, unlike the adjacent spinel (MgAl2O4), purple in color in (h). Credit: The Astrophysical Journal Letters (2022). DOI: 10.3847/2041-8213/ac83bd

An international team of researchers studying dust samples retrieved by the Hayabusa-2 space probe, has found that some of its dust grains are older than the solar system. In their paper published in The Astrophysical Journal Letters, the group describes their analysis of the dust from the asteroid and what they found.

The Hayabusa-2 space probe began its mission back in 2014 as it was launched into space aboard a H-IIA 202 rocket. It rendezvoused with the near-Earth asteroid 162173 Ryugu four years later. After circling the asteroid for two years, it descended to its surface and grabbed a sample of its surface dust. It then blasted off and made its way back to Earth.

Ryugu is situated 300 million kilometers from Earth and circles the sun every 16 months. It has been described as little more than an assemblage of gravel, likely made from the debris of several other asteroids. Other research has shown that it likely formed in the outer part of the solar system and has been creeping inward since—others yet suggest its dust hints at the possibility of Earth’s water coming from a similar asteroid.

Since the sample of dust collected by the probe returned to Earth, parts of it have been passed around the world to different researchers eager to test it in different ways. In this new effort, the researchers looked to determine its age—they note that different kinds of grains in asteroids such as Ryugu originated from different types of stars and stellar processes. The age of the grains in their dust can be identified and dated by their isotopic signatures.

In studying the Ryugu dust sample, the researchers compared them to grains found in carbonaceous chondrite meteorites that have been found on Earth. They note that just 5% of such meteorites have been found to harbor grains that predate the creation of the solar system—some of which have been dated to 7 billion years ago. The researchers found that the dust sample held grains identical to all of the others that have been seen in meteorites, showing that it too predates the solar system. They note that one in particular, a silicate that is known to be very easily destroyed, must have been protected somehow from damage by the sun.

Space mission shows Earth’s water may be from asteroids: study

More information:
Jens Barosch et al, Presolar Stardust in Asteroid Ryugu, The Astrophysical Journal Letters (2022). DOI: 10.3847/2041-8213/ac83bd

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Citation:
Grains of dust from asteroid Ryugu older than our solar system (2022, August 18)
retrieved 18 August 2022
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World

Russia Strikes Odessa Port After Signing Deal to Unblock Ukrainian Grain Exports

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KYIV, Ukraine—Russia launched a missile attack on Ukraine’s key grain-exporting port of Odessa, officials said, hours after signing an international agreement to ease its blockade of the Black Sea coastline and allow for the safe transport of grain and other foodstuffs necessary to alleviate a looming global food crisis.

The attack on Odessa appeared to violate the terms of the United Nations-brokered agreement signed by Russia and Ukraine in Istanbul on Friday, which stipulated that both countries would refrain from attacking port facilities or civilian ships used for grain transport, according to a copy of the agreement reviewed by The Wall Street Journal. U.N. Secretary-General

António Guterres

condemned the strike, saying in a statement that all parties had committed to ensuring the safe movement of Ukrainian grain shipments.

At least two Russian Kalibr cruise missiles hit Odessa, the only major Ukrainian port resisting Russian occupation, damaging infrastructure at the site, Ukraine officials said. Another two of the missiles, which Russia has been launching from warships and submarines, were shot down by aerial defenses, officials said.

A railcar discharging point and a warehouse used for loading grain were destroyed in the attack, according to international grain traders.

The target of the strike was likely a nearby shipbuilding yard, workers at the port said.

“It’s obvious that the agreement with Russia is not even worth the paper it was signed on…Russia is a terrorist state,” said Ukraine’s ambassador to Turkey,

Vasyl Bodnar,

who was present at the signing of the agreement.

Ukrainian Foreign Ministry spokesman

Oleg Nikolenko

said the attack on Odessa was like spitting in the face of the U.N. and Turkey, which facilitated and hosted the negotiations.

“We urge the U.N. and Turkey to ensure Russia’s compliance with its obligations to provide a safe corridor for the grain exports,” Mr. Nikolenko said in a statement posted to Facebook.

A resident of Kharkiv, northeastern Ukraine, on Saturday carried items out of an apartment damaged by a Russian attack.



Photo:

STRINGER/REUTERS

Russia’s Defense Ministry didn’t respond to a request for comment, nor was there any comment from the Kremlin.

Turkish officials who helped broker the agreement said they had been in contact with Russia, which denied being behind the attack.

“The Russians told us that they had absolutely nothing to do with this attack and that they were examining the issue very closely and in detail. The fact that such an incident occurred right after the agreement we made yesterday regarding the grain shipment really worried us as well,” said Turkey’s Defense Minister

Hulusi Akar

in a statement on Saturday.

Mr. Akar signed the agreements with Ukraine and Russia on behalf of Turkey on Friday. He added that Ankara would continue to fulfill its duties under the grain agreement, which calls on Turkey to help monitor the accord and inspect shipments.

Russia also struck a military airport and a railway station on Saturday in central Ukraine, authorities said, in another long-range attack reaching far beyond the immediate front lines. Ukraine, meanwhile, is continuing to take advantage of Western weapons to stall Russia’s military advance.

Andriy Raikovych,

head of the Kirovohrad region in central Ukraine, said 13 missiles were fired at infrastructure and military facilities overnight, leaving at least three people dead and 13 wounded. Another strike, on Mykolaiv in the south, destroyed a warehouse, authorities there said.

Odessa, the only key port city on the Black Sea still held by Ukraine, was also shelled Saturday, with local media reporting seven missile strikes inside the urban area.

Ukraine’s forces meanwhile used U.S.-made Himar rocket launchers in a systematic shelling campaign seemingly aimed at cutting off vital supplies from the strategically important southern region of Kherson, which Russia has occupied since early in the invasion, Russian and Ukrainian officials said.

Kyiv’s use of Himars launchers to bombard two strategic bridges over the Dnipro and Inhulets rivers has already made tank and truck traffic between Kherson and Russia near-impossible, according to officials and footage from the ground circulating on social media. Ukrainian officials have said that they are preparing a counteroffensive to liberate the Kherson region.

Residents of cities throughout Ukraine have largely become accustomed to the sound of air-raid sirens portending a possible rocket attack, with the majority disregarding advice to find the nearest underground shelter and wait until the danger has passed. Mr. Raikovych asked them to reconsider.

“I continually urge you to not ignore the sirens and immediately go to a shelter,” he wrote on the Telegram messaging app.

The latest round of attacks beyond the front lines comes as Ukrainian forces slow the Russian campaign to take the Donbas region in the east. Ukraine’s strikes on arms depots and strategic bridges in Russian-occupied territory, and its effective use of Himars rocket systems and other Western-supplied arms, have made it much harder for Russia to solidify its occupation in certain regions and to maintain the relentless artillery barrages that have underpinned its piecemeal but steady advance since April.

Analysts say a brief operational pause earlier this month following Russia’s capture of the eastern Luhansk region has given its troops too little time to recover before their campaign resumed this week.

Part of a rocket protrudes from a wheat field in the Kharkiv region.



Photo:

sergey bobok/Agence France-Presse/Getty Images

“Russian forces are degraded, they are beat up, tired and exhausted, and they need to regroup in order to be able to regain some of the combat effectiveness which they’d lost over the course of the Donbas campaign and the overall war,” said George Barros, an analyst at the Washington-based Institute for the Study of War. “An approximately 10-day operational pause is not sufficiently long for the Russian forces to be able to regain the strength that they need.”

While the battlefield picture has ossified in recent days, diplomatic avenues to resolve the crisis have made some headway. In the agreement aimed at ending the grain crisis caused by the war, Ukraine and Russia paved the way for the resumption of exports from Black Sea ports blocked by Russian ships. Delegates from the two countries signed parallel deals Friday at a ceremony in Istanbul, following months of diplomacy led by Turkey and the United Nations.

The agreement could free up about 18 million tons of wheat, corn and other supplies that have been stuck at Ukrainian ports and grain silos for weeks. Grain analysts have said they expect it could take weeks for grain shipments to begin flowing again, if both sides remain committed to the deal.

Late on Friday, Ukraine said operations at some of its ports may resume in as little as three days. Yury Vaskov, Ukraine’s deputy infrastructure minister and a member of the country’s delegation at the talks in Istanbul, told Ukrainian media on Friday that the port of Chornomorsk south of Odessa is preparing to handle the first vessel carrying grain.

River traffic on Thursday near the port of Reni, on the Ukrainian stretch of the Danube.



Photo:

Sergii Kharchenko/Zuma Press

The most active wheat futures contract fell 5.9%, to $7.59 per bushel, in trading on the Chicago Board of Trade Friday, as the deal raised hopes that a restart to Ukrainian grain exports would ease a brewing global food-supply crisis.

The deal has been seen as a limited but promising step toward bringing the two sides closer to a peace deal. Some European Union countries have suggested Ukraine should make concessions to Russia in exchange for peace. But in an interview with The Wall Street Journal on Friday, Ukrainian President

Volodymyr Zelensky

said any pause in the fighting could merely give battered Russian forces a chance to regroup and rearm.

Instead he called for further weapons supplies from the West, and credited the support of Ukraine’s allies for shifting the balance on the battlefield and allowing Ukraine to bog down Russian troops fighting to capture swaths of the country’s east. Shortly after he spoke, the White House on Friday announced another $270 million worth of weapons for Ukraine, including four more Himars and hundreds more Phoenix Ghost drones.

The U.S. also said that the Pentagon is considering providing Ukrainian forces with jet fighters. It is “making some preliminary explorations into the feasibility of potentially providing fighter aircraft to the Ukrainians,” said John Kirby, the National Security Council coordinator for strategic communication. U.S. officials have previously resisted supplying Ukraine with jet fighters over concerns that they could risk a more direct conflict with Moscow.

Write to Matthew Luxmoore at Matthew.Luxmoore@wsj.com, Bojan Pancevski at bojan.pancevski@wsj.com and Jared Malsin at jared.malsin@wsj.com

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Science

A 4-Billion-Year-Old Piece of Earth’s Crust Has Been Identified Beneath Australia

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Scientists can use various clues to figure out what’s under Earth’s surface without actually having to do any digging – including firing super-fine lasers thinner than a human hair at minerals found in beach sand.

 

This technique has been used in a new study that points to a 4-billion-year-old piece of Earth’s crust about the size of Ireland, which has been sitting under Western Australia and influencing the geological evolution of the area across millions of millennia.

It might be able to provide clues to how our planet went from being uninhabitable to supporting life.

The researchers think that the huge expanse of crust would have heavily influenced the formation of rocks as old materials were mixed with new, having first appeared as one of the planet’s earliest protocrust formations and surviving multiple mountain-building events.

“When comparing our findings to existing data, it appears many regions around the world experienced a similar timing of early crust formation and preservation,” says geology PhD student and lead author Maximilian Dröellner, from Curtin University in Australia.

“This suggests a significant change in the evolution of Earth some 4 billion years ago, as meteorite bombardment waned, crust stabilized, and life on Earth began to establish.”

The lasers were used to vaporize grains of the mineral zircon, taken from sand sampled from rivers and beaches in Western Australia.

 

Technically known as laser ablation split stream-inductively coupled plasma-mass spectrometry, the method enables scientists to date the grains and compare them with others to see where they might have come from.

This gave the team an insight into the crystalline basement under Earth’s surface in this particular region – showing where the grains had originally eroded from, the forces used to create them, and how the geology of the region had built up over time.

As well as the significance of the protocrust remnant still being there – about 100,000 square kilometers (38,610 square miles) of it – the boundaries of the block will also help scientists to chart out what else is hidden away under Earth’s surface, and how it might have evolved to be in its current state.

“The edge of the ancient piece of crust appears to define an important crustal boundary controlling where economically important minerals are found,” says research supervisor geologist Milo Barham, from Curtin University.

“Recognizing these ancient crustal remnants is important for the future of optimized sustainable resource exploration.”

As you might expect after 4 billion years, there’s not much left of Earth’s original crust to study, which makes findings like this one all the more interesting and useful to experts – giving us an important window into the distant past.

 

The shifting of Earth’s crust and the swirling of the hot mantle underneath are difficult to predict and to retrospectively map out. When evidence of interior movement and geology can be found on the surface, scientists are therefore very keen to make use of it.

Further down the line, the results of the study described here could also help scientists who are looking at other planets – the way these planets are formed, how their earliest crust is shaped, and even how alien life might get established on them.

“Studying the early Earth is challenging given the enormity of time that has elapsed, but it has profound importance for understanding life’s significance on Earth and our quest to find it on other planets,” says Barham.

The research has been published in the journal Terra Nova.

 

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World

Russia Pushes to Seize Chemical Plant in Severodonetsk as Ukraine Detains Suspected Spies

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KYIV, Ukraine—Russia on Tuesday intensified its major offensive to take a chemical plant that has become the last bastion for Ukrainian forces in the strategic eastern city of Severodonetsk, as Ukrainian authorities called for more military aid and detained two of its own officials on suspicion they spied for Russia.

Serhiy Haidai,

the Ukrainian governor of the Luhansk region, said all regional towns that aren’t under Russia’s control are being shelled by its forces as Moscow mounts relentless artillery barrages in an attempt to complete its capture of Donbas.

President

Volodymyr Zelensky

late on Monday again appealed to the international community to help ensure that Ukraine’s fight against Russian forces doesn’t fade from global attention, saying he would do everything possible to achieve that.

A Ukrainian soldier on the front line in Shevchenkove, a village east of Kyiv.



Photo:

Guillaume Binet / MYOP for The Wall Street Journal

The last check point before the village of Pryshyb, Ukraine. Russian forces hold another village nearby.



Photo:

Guillaume Binet / MYOP for The Wall Street Journal

The conflict has morphed into a war of attrition, with Russia deploying heavy artillery to outgun Ukrainian forces. Mr. Zelensky has been pleading with Western leaders to send Kyiv more supplies of howitzers and other heavy weapons to counter the barrage.

“This is an evil that can only be defeated on the battlefield,” he said of Russia’s invasion. “We are defending Lysychansk and Severodonetsk. Throughout this whole region, the toughest, most serious battles are taking place.”

Ukraine has been counting on Central European countries that were subjugated by Moscow during the Cold War to donate Soviet-era equipment that Ukrainians have the training and spare parts to maintain. Slovakia has sent Soviet-type helicopter gunships, grad rockets, howitzers and an S-300 air-defense system.

But most of those countries are only willing to do so if they can buy replacement systems from the North Atlantic Treaty Organization’s allies such as Germany, France or the U.S. Germany’s limited supply of equipment and production bottlenecks have left it unable to provide those countries with all the weaponry they need to keep giving Ukraine more.

On Tuesday, Slovakia said a plan to donate a tank battalion to Ukraine fell through after Germany was unable to supply the tanks Slovakia needed.

Under the plan, Slovakia would have given 30 T-72 Soviet-type tanks to Ukraine, enough for a tank battalion, the Slovak Defense Ministry’s spokeswoman said. For months, the Central European government had been in talks with Berlin to replace those tanks with modern German Leopard tanks. But Germany, Slovakia said, now says it can only offer Slovakia 15 Leopard main battle tanks.

“The Slovak Ministry of Defense is intensely seeking ways to aid Ukraine, however this is being done on the principle of solidarity, ensuring that our solutions are advantageous for all sides,” said Slovak Defense Ministry communications director Martina Kakaščíková.

A spokesman for the German government didn’t immediately respond to a request for comment on the tanks. Ukrainian Defence Minister

Oleksiy Reznikov

thanked the German government for sending the long-range howitzers, which he said would be put to full use in the battlefield. The shipment was made, a German official said, after Ukrainian troops had completed training for the systems in Germany.

In occupied regions of Ukraine, Russia is handing out passports, teaching its version of history, and sending trucks blasting the Kremlin’s propaganda. But convincing people to support the invader can be complicated. WSJ’s Thomas Grove reports. Photo: Sergei Ilnitsky/EPA-EFE/Shutterstock

Ukraine’s domestic intelligence agency, the SBU, has meanwhile moved to clamp down on people it suspects of working on Russia’s behalf in occupied areas and in government structures elsewhere.

The SBU said on Tuesday that it had detained two men suspected of spying for Russia, one working as a deputy in the cabinet of ministers and the other as director of one of the departments in the country’s chamber of commerce and industry.

In a video posted to Telegram, SBU spokesman Artem Dekhtyarenko said the officials had been passing classified information to Russia, ranging from details about Ukraine’s defense capabilities to the personal data of Ukrainian law-enforcement personnel. He said Russian handlers paid sums of up to $15,000 for an assignment to the two men. Russia didn’t immediately comment on the allegations.

The two officials, whose names weren’t given in the video, were shown saying they had been recruited by Russia’s Federal Security Service. It couldn’t be determined if they were speaking under duress or if they had legal representation.

Also on Tuesday, Ukrainian Prosecutor General Iryna Venediktova met with U.S. Attorney General

Merrick Garland

in Ukraine to discuss U.S. and international efforts to help Ukraine identify, apprehend and prosecute individuals involved in war crimes and other atrocities. Ukrainian prosecutors have said they are investigating more than 10,700 potential war crimes involving more than 600 suspects.

Meanwhile, Kremlin spokesman Dmitry Peskov reiterated to reporters on Tuesday that he couldn’t guarantee that two American military veterans feared captured in Ukraine wouldn’t face the death penalty. Alexander Drueke, 39, and Andy Tai Ngoc Huynh, 27, both from Alabama, volunteered to serve alongside Ukrainian forces.

“We can’t rule anything out, because this is a decision for the court,” Mr. Peskov said.

A refugee center in Odessa, Ukraine, which is supporting hundreds of people fleeing the war.



Photo:

Serhii Korovayny for The Wall Street Journal

Ukrainian student sailors near the opera house in Odessa, Ukraine.



Photo:

Serhii Korovayny for The Wall Street Journal

John Kirby, a national security spokesman for the White House, said Tuesday that the government was still trying to learn more about the two men and criticized the Russian threat.

“It’s appalling that a public official in Russia would even suggest the death penalty for the two American citizens,” Mr. Kirby said. “We’ve got more homework here to do. But I do think it’s important for us to make it clear: Truly appalling for even the suggestion” that the men could be put to death.

Authorities in the self-proclaimed Donetsk People’s Republic, which broke away from Ukraine with Russian arms and financing in 2014, recently sentenced to death three foreigners—two from the U.K. and one from Morocco—after they were captured fighting alongside Ukrainian forces against Russian-backed troops near Mariupol.

Russia has accused Ukraine of attacking strategic objects on territory under its control.

Sergei Aksyonov,

the Russian-appointed head of the Crimean Peninsula that was annexed by Russia from Ukraine in 2014, wrote on Telegram on Monday that Ukrainian forces had struck drilling platforms owned by gas company Chernomorneftegaz, injuring three people.

The apparent Ukrainian attack on the gas rigs has prompted a search-and-rescue operation in Crimea and is expected to cost Russian authorities billions of dollars in damage and lost revenue. Just hours after Mr. Aksyonov reported the attack, Russia launched a series of rockets toward Odessa in Ukraine’s south, scrambling the city’s air defenses and causing some residents to flee to bomb shelters in fear of the largest assault on the city in recent weeks.

Russian President

Vladimir Putin

on Tuesday told military-school graduates that Russian forces had started receiving S-500 air and missile defense systems. The Sarmat intercontinental ballistic missile will be ready for combat at the end of the year, said Mr. Putin. He oversaw the first test-launch of the RS-28 Sarmat system in April.

Russia would “continue to develop and strengthen our armed forces, taking into account potential military threats and risks based on the lessons of contemporary armed conflicts,” Mr. Putin said.

Russian journalist Dmitry Muratov on Monday raised $103.5 million for Ukrainian child refugees after auctioning off the Nobel Peace Prize he won last year. “I was hoping that there was going to be an enormous amount of solidarity,” Mr. Muratov said after the sale, which shattered the record haul for a Nobel medal. “But I was not expecting this to be such a huge amount.”

Mr. Muratov is a co-founder and editor in chief of the now-closed independent Russian newspaper Novaya Gazeta, an outlet that had for years published investigations on state corruption and the role of Russia’s military on the world stage.

Meanwhile, the continued blockage of Ukraine’s sea ports is intensifying an export crisis that has left millions of metric tons of grain stranded in the country and unable to reach countries that desperately need it. Kyiv has sought to move out the grain by land, but the amount that can be transported by rail and truck pales in comparison with that shipped each year through southern ports.

Also in his address late Monday, Mr. Zelensky said capacity at the Krakovets-Korczowa checkpoint on the border with Poland had been increased by 50%, a move he expects to facilitate the flow of some grain out of the country.

“Modernization awaits other checkpoints on the borders with the European Union,” Mr. Zelensky said.

A Ukrainian soldier in a roadside bunker near the village of Bashtanka.



Photo:

Guillaume Binet/MYOP for The Wall Street Journal

—Bojan Pancevski contributed to this article.

Write to Matthew Luxmoore at Matthew.Luxmoore@wsj.com, Drew Hinshaw at drew.hinshaw@wsj.com and Mauro Orru at mauro.orru@wsj.com

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Business

Commodity Funds Draw Bets Ukraine Invasion, Russia Sanctions Will Stoke Rally

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Investors are raising bets that the invasion of Ukraine and sanctions on Russia will further fuel an already-hot commodities rally.

War has gripped global markets, lifting prices for a number of raw materials. Wheat has surged to its highest level since 2008. Corn prices have jumped around 25% so far this year, earlier this week touching their highest levels since March 2013 before paring gains. Aluminum and nickel have jumped to their highest levels in over a decade. 

Federal Reserve Chairman

Jerome Powell

said Wednesday he would propose a rate increase of a quarter-percentage point at the central bank’s meeting in mid-March, spurring wagers that the Fed won’t react too aggressively to curb inflation. 

These developments have helped general commodity mutual funds and exchange-traded funds report net inflows for the eighth consecutive week through Wednesday, according to data from Refinitiv Lipper. That marks the longest streak since a 23-week run that ended in June 2021. Inflows for the week ended March 2, at $867 million, were at a record high, according to data going back to 2011.

The surge extends gains in commodities, many of which reached multiyear highs in 2021. Analysts said global supply of several commodities, already tight because of supply-chain obstacles, unfavorable weather and strong demand, could be strained further. 

“People are looking for a way to get out of inflation’s impact, and commodities really look like a good hedge,” said

Hakan Kaya,

senior portfolio manager at Neuberger Berman, whose firm has increased exposure across commodities from energy to livestock and agriculture in 2022.

Commodity prices tend to rise alongside inflation, and investors often use them to hedge portfolios. Commodity funds invest in both commodity-linked derivatives and the underlying commodities themselves.

The S&P GSCI index, a benchmark for commodities, has added about 30% so far this year, while the broad-based S&P 500 has retreated around 10%. The Bloomberg Commodity Index has gained around 30% during that period.

“This is the type of environment where commodities have proven their worth in terms of why they are in the portfolio in the first place,” said

Matt Stucky,

senior portfolio manager at Northwestern Mutual Wealth Management Co.

Seven-year highs in energy prices are contributing to the boost in commodities. Brent crude, the global oil benchmark, has risen around 50% so far this year, recently trading above $118 a barrel. Higher energy prices have spillover effects: Smelters could cut back on the production of metals, for example, while farmers could pay more to transport grains.

While investors can benefit from rising commodities prices, they pose broader economic concerns. Analysts said higher inflation alongside lower economic growth could increase the risk of recession. Meanwhile, investors are watching the events in Ukraine and the effect of sanctions on Russia. 

“Broad-based commodity exposures have performed strongly and continue to make sense as the conflict continues; ongoing and further escalation can and would likely lead to higher index levels still,” RBC analysts wrote in a Tuesday note.

While Ukraine endures military assaults by Russian forces, analysts are warning that the world’s wheat supply could be severely threatened. WSJ’s Shelby Holliday explains. Photo: Valentyn Ogirenko/Reuters

Write to Hardika Singh at hardika.singh@wsj.com

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Science

There’s a Hidden Mathematical ‘Law’ in The Sand Megaripples Found All Over Earth

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Wherever there is sand and an atmosphere, prevailing winds may whip the grains into undulating shapes, pleasing to the eye with their calming repetition.

Certain sand waves, with wavelengths between 30 centimeters (almost 12 inches) and several meters (around 30 feet), are known as megaripples: they’re between ordinary beach ripples and full dunes in size, and we’ve seen them not just on Earth, but even on other planets such as Mars, well known for its all-encompassing dust storms.

 

Aside from their size, a key characteristic of these middle-ground ripples is the grain size involved – a surface of coarse grains over an interior of much finer material. Yet this mix of grains is never the same, and nor are the winds that blow across the sand to create the ripples in the first place.

Now researchers have discovered a surprising mathematical feature of megaripples: Dividing the diameter of the coarsest grains in the mix with the diameter of the smallest grains always equals a similar number – something that hasn’t been spotted before across several decades of research.

Transverse aeolian ridges, a type of megaripple seen on Mars. (NASA/JPL-Caltech/Univ. of Arizona)

In the future, this number could be used to categorize different types of ripples and which particular grain transport processes formed them, the study authors conclude.

“We found that a characteristic signature of grain-scale transport is encoded in the grain-size distributions (GSDs) that co-evolve with megaripples,” write the researchers in their published paper.

“Our compilation of original and literature data firmly establishes the accuracy and robustness of the theoretical prediction across a wide range of geographic locations and prevailing environmental conditions.”

 

As winds whip across the sand, megaripples are caused by fine grains kicking up coarser ones. Traveling at different rates, the coarse grains collect on the crests of the ripples, while the fine grains usually settle in the troughs.

Samples were studied from megaripple fields in Israel, China, Namibia, India, Israel, Jordan, Antarctica and New Mexico in the US. Further analysis was added from observations made on Mars and in a lab wind tunnel.

“A comprehensive collection of terrestrial and extraterrestrial data, covering a wide range of geographical sources and environmental conditions, supports the accuracy and robustness of this unexpected theoretical finding,” write the researchers.

What also sets megaripples apart is that they’re more fragile than smaller sand ripples and larger dunes, and more susceptible to the whims of shifting wind patterns – if the wind gets too strong, the mechanisms creating the megaripples get overpowered.

The researchers suggest that their calculations could also be used to predict when this will happen, and even to look back at past weather and climate conditions based on the sediment left behind by previous megaripples.

 

The findings even apply beyond Earth: they could give us a better understanding of how megaripples are created on planets such as Mars, and the sort of atmospheric conditions required to produce them rather than other types of sand waves.

“If we were able to use prevailing atmospheric conditions to explain the origin and migration of terrestrial and extraterrestrial sand waves, this would be an important step,” says theoretical physicist Katharina Tholen, from Leipzig University.

“It might then be possible to evaluate the sand structures we are currently observing, for example on Mars or in fossils and remote locations on Earth, as complex archives of past climatic conditions.”

The research has been published in Nature Communications.

 

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