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Groundwater level threatens to fall in Germany due to climate change

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Groundwater level threatens to fall in Germany due to climate change

Climate change directly affects groundwater resources. Groundwater levels in Germany threaten to fall in the next decades. This is the result of a study made by Karlsruhe Institute of Technology (KIT) and the Federal Institute for Geosciences and Natural Resources (BGR). It is now published in Nature Communications.

The experts from BGR and KIT used AI-based forecast models to find out how climate change will affect groundwater resources in Germany in the 21st century. They applied deep learning methods to assess on the basis of groundwater data from all over the Germany the development of groundwater levels for different locations and climate scenarios defined by the Intergovernmental Panel on Climate Change (IPCC). These scenarios ranged from an assumed increase of global mean temperature by less than 2 degrees Celsius until 2100, the target defined by the Paris Climate Agreement, to a moderate scenario (plus 2.6 degrees) to the so-called business-as-usual scenario that is based on the absence of any climate protection measures and an increase in temperature by up to 5 degrees compared to the pre-industrial level. “Our scientific study exclusively covered direct climatic impacts and changes. Anthropogenic factors, such as groundwater extraction, were not considered,” says Andreas Wunsch from KIT’s Institute of Applied Geosciences (AGW), first author of the study.

Groundwater level threatens to fall in Germany due to climate change
Left: Mean changes of the groundwater level (in percent) in 2100 compared to 2014 for all locations studied and climate projections for the business-as-usual scenario.Right: Heat maps of the modeled groundwater levels for an exemplary location. Credit: KIT/BGR

Forecasts reveal falling groundwater levels are independent of the scenario

According to the experts, all three climate scenarios studied lead to more or less strong developments with droughts, falling groundwater levels, and a changed water availability. While less pronounced trends were obtained for the two more optimistic scenarios, KIT and BGR experts found a trend toward significantly falling groundwater levels at most locations for the strongest of the three warming scenarios. “The results of this prognosis are particularly relevant to the near future, as this scenario is closest to today’s situation,” says Dr. Tanja Liesch, AGW.

“Future negative impacts will be particularly visible in North and East Germany, where the corresponding developments have already started. Here, longer periods of low groundwater levels threaten to occur by the end of the century in particular,” says Dr. Stefan Broda, BGR. For the two weaker warming scenarios, this trend is not that severe. KIT and BGR experts think that this indicates that the reduction of greenhouse gas emissions may have a positive impact on future groundwater levels.

The published results were obtained within the BGR project MENTOR that is aimed at developing an AI-based method for nationwide forecast of groundwater levels.

More information: Andreas Wunsch et al, Deep learning shows declining groundwater levels in Germany until 2100 due to climate change, Nature Communications (2022). DOI: 10.1038/s41467-022-28770-2
Provided by Karlsruhe Institute of Technology.

4 billion-year-old relic from early solar system heading our way

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4 billion-year-old relic from early solar system heading our way

An enormous comet—approximately 80 miles across, more than twice the width of Rhode Island—is heading our way at 22,000 miles per hour from the edge of the solar system. Fortunately, it will never get closer than 1 billion miles from the sun, which is slightly farther from Earth than Saturn; that will be in 2031.

Comets, among the oldest objects in the solar system, are icy bodies that were unceremoniously tossed out of the solar system in a gravitational pinball game among the massive outer planets, said David Jewitt. The UCLA professor of planetary science and astronomy co-authored a new study of the comet in the Astrophysical Journal Letters. The evicted comets took up residence in the Oort cloud, a vast reservoir of far-flung comets encircling the solar system out to many billions of miles into deep space, he said.

A typical comet’s spectacular multimillion-mile-long tail, which makes it look like a skyrocket, belies the fact that the source at the heart of the fireworks is a solid nucleus of ice mixed with dust—essentially a dirty snowball. This huge one, called Comet C/2014 UN271 and discovered by astronomers Pedro Bernardinelli and Gary Bernstein, could be as large as 85 miles across.

“This comet is literally the tip of the iceberg for many thousands of comets that are too faint to see in the more distant parts of the solar system,” Jewitt said. “We’ve always suspected this comet had to be big because it is so bright at such a large distance. Now we confirm it is.”

This comet has the largest nucleus ever seen in a comet by astronomers. Jewitt and his colleagues determined the size of its nucleus using NASA’s Hubble Space Telescope. Its nucleus is about 50 times larger than those of most known comets. Its mass is estimated to be 500 trillion tons, a hundred thousand times greater than the mass of a typical comet found much closer to the sun.

“This is an amazing object, given how active it is when it’s still so far from the sun,” said lead author Man-To Hui, who earned his doctorate from UCLA in 2019 and is now with the Macau University of Science and Technology in Taipa, Macau. “We guessed the comet might be pretty big, but we needed the best data to confirm this.”

So the researchers used Hubble to take five photos of the comet on Jan. 8, 2022, and incorporated radio observations of the comet into their analysis.

4 billion-year-old relic from early solar system heading our way
Diagram comparing the size of the icy, solid nucleus of comet C/2014 UN271 (Bernardinelli-Bernstein) to several other comets. Credit: NASA, ESA, Zena Levy (STScI)

The comet is now less than 2 billion miles from the sun and in a few million years will loop back to its nesting ground in the Oort cloud, Jewitt said.

Comet C/2014 UN271 was first serendipitously observed in 2010, when it was 3 billion miles from the sun. Since then, it has been intensively studied by ground and space-based telescopes.

The challenge in measuring this comet was how to determine the solid nucleus from the huge dusty coma—the cloud of dust and gas—enveloping it. The comet is currently too far away for its nucleus to be visually resolved by Hubble. Instead, the Hubble data show a bright spike of light at the nucleus’ location. Hui and his colleagues next made a computer model of the surrounding coma and adjusted it to fit the Hubble images. Then, they subtracted the glow of the coma, leaving behind the nucleus.

Hui and his team compared the brightness of the nucleus to earlier radio observations from the Atacama Large Millimeter/submillimeter Array, or ALMA, in Chile. The new Hubble measurements are close to the earlier size estimates from ALMA, but convincingly suggest a darker nucleus surface than previously thought.

“It’s big and it’s blacker than coal,” Jewitt said.

The comet has been falling toward the sun for well over 1 million years. The Oort cloud is thought to be the nesting ground for trillions of comets. Jewitt thinks the Oort cloud extends from a few hundred times the distance between the sun and the Earth to at least a quarter of the way out to the distance of the nearest stars to our sun, in the Alpha Centauri system.

The Oort cloud’s comets were tossed out of the solar system billions of years ago by the gravitation of the massive outer planets, according to Jewitt. The far-flung comets travel back toward the sun and planets only if their orbits are disturbed by the gravitational tug of a passing star, the professor said.

First hypothesized in 1950 by Dutch astronomer Jan Oort, the Oort cloud still remains a theory because the comets that make it up are too faint and distant to be directly observed. This means the solar system’s largest structure is all but invisible, Jewitt said.

More information: Man-To Hui et al, Hubble Space Telescope Detection of the Nucleus of Comet C/2014 UN271 (Bernardinelli–Bernstein), The Astrophysical Journal Letters (2022). DOI: 10.3847/2041-8213/ac626a
Journal information: Astrophysical Journal Letters
Provided by University of California, Los Angeles.

China’s ‘space dream’: A Long March to the Moon and beyond

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China’s ‘space dream’: A Long March to the Moon and beyond

The return to Earth of three astronauts on Saturday after six months at China’s new space station marks a landmark step in the country’s space ambitions, ending its longest crewed mission ever.

The world’s second-largest economy has put billions into its military-run space programme, with hopes of eventually sending humans to the Moon.

China has come a long way in catching up with the United States and Russia, whose astronauts and cosmonauts have decades of experience in space exploration.

Here is a look at the country’s space programme, and where it is headed:

Mao’s vow

Soon after the Soviet Union launched Sputnik in 1957, Chairman Mao Zedong pronounced: “We too will make satellites.”

It took more than a decade, but in 1970, China launched its first satellite on a Long March rocket.

Human spaceflight took decades longer, with Yang Liwei becoming the first Chinese “taikonaut” in 2003.

As the launch approached, concerns over the viability of the mission caused Beijing to cancel a live television broadcast at the last minute.

But it went smoothly, with Yang orbiting the Earth 14 times during a 21-hour flight aboard the Shenzhou 5.

China has launched seven crewed missions since.

Space station and ‘Jade Rabbit’

The Jade Rabbit lunar rover surveyed the moon's surface for 31 months
The Jade Rabbit lunar rover surveyed the moon’s surface for 31 months.

Following in the footsteps of the United States and Russia, China began planning to build its own space station circling the planet.

The Tiangong-1 lab was launched in 2011.

In 2013, the second Chinese woman in space, Wang Yaping, gave a video class from inside the space module to children across the world’s most populous country.

The craft was also used for medical experiments and, most importantly, tests intended to prepare for the construction of a space station.

That was followed by the “Jade Rabbit” lunar rover in 2013, which initially appeared a dud when it turned dormant and stopped sending signals back to Earth.

It made a dramatic recovery, however, ultimately surveying the Moon’s surface for 31 months—well beyond its expected lifespan.

In 2016, China launched its second orbital lab, the Tiangong-2. Astronauts who visited the station have run experiments on growing rice and other plants.

‘Space dream’

Under President Xi Jinping, plans for China’s “space dream” have been put into overdrive.

Beijing is looking to finally catch up with the United States and Russia after years of belatedly matching their milestones.

Besides a space station, China is also planning to build a base on the Moon, and the country’s National Space Administration said it aims to launch a crewed lunar mission by 2029.

But lunar work was dealt a setback in 2017 when the Long March-5 Y2, a powerful heavy-lift rocket, failed to launch on a mission to send communication satellites into orbit.

That forced the postponement of the Chang’e-5 launch, originally scheduled to collect Moon samples in the second half of 2017.

Another robot, the Chang’e-4, landed on the far side of the Moon in January 2019—a historic first.

This was followed by one that landed on the near side of the Moon last year, raising a Chinese flag on the lunar surface.

The unmanned spacecraft returned to Earth in December with rocks and soil—the first lunar samples collected in four decades.

And in February 2021, the first images of Mars were sent back by the five-tonne Tianwen-1, which then landed a rover on the Martian surface in May that has since started to explore the surface of the Red Planet.

Palace in the sky

A trio of astronauts docked successfully in October with the core Tianhe module of the Chinese space station, which was placed in orbit in April 2021.

The astronauts stayed at the station for six months before returning safely to Earth on Saturday, ending China’s longest crewed mission to date.

The Chinese space station Tiangong—meaning “heavenly palace”—will need a total of around 11 missions to bring more parts and assemble them in orbit.

Once completed, it is expected to remain in low Earth orbit at between 400 and 450 kilometres (250 and 280 miles) above our planet for at least 10 years—realising an ambition to maintain a long-term human presence in space.

While China does not plan to use its space station for global cooperation on the scale of the International Space Station, Beijing said it is open to foreign collaboration.

It is not yet clear how extensive that cooperation will be.

Some cities, states say Big Oil should pay for climate damage

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Some cities, states say Big Oil should pay for climate damage

In the waning days of 2021, a grass fire broke out in Boulder County, Colorado. Fueled by extreme drought and high winds, the fire swept through the communities of Superior and Louisville. Within hours, it had destroyed more than a thousand structures—making the Marshall fire the most destructive in the state’s history.

The December fire was an extraordinary event, but perhaps a preview of the new normal under the conditions caused by climate change. Late last month, another fire forced the evacuation of 18,000 residents in and around Boulder. Fortunate winds saved the city from catastrophic damage, but the near-miss—and the timing well outside of the region’s traditional fire season—was a warning sign of what’s to come.

“We’ve already experienced impacts (from climate change), but nowhere near the amount that we’re likely to experience in the coming decades,” said Aaron Brockett, Boulder’s mayor. “We have a lot of work to do to make our community more resilient.”

Boulder leaders are working to reduce fuel loads in the forests and open spaces owned by the city. They’re seeking to make the neighborhoods bordering those lands more fire resilient. They’re hoping to upgrade fire stations and equipment. And they’re planning projects to reduce flood risk from the severe storms that climate change is likely to bring.

That work will cost tens, if not hundreds, of millions of dollars. And local leaders think oil companies should pay for it.

In February, the city and county of Boulder, along with San Miguel County in western Colorado, scored a significant win in their legal fight against Exxon Mobil and Suncor energy companies when a federal appeals court ruled that the case would remain in state court.

Local governments earned another win last week when a different federal appeals court ruled that Baltimore’s case against oil companies also belonged in state court.

The decisions were the first under new U.S. Supreme Court guidelines, established last May as part of Baltimore’s climate lawsuit, directing appeals courts to take a more expansive look at oil companies’ arguments that the cases belong in federal court. The rulings have been closely watched by the nearly two dozen states, cities and counties that have filed lawsuits likewise seeking payment from fossil fuel companies for the damages caused by climate change.

Oil companies, with the backing of some other states, have fought to move the cases to federal court, where they think national regulations around drilling, refining, emissions and air quality would invalidate the legal claims against them. The local governments that have sued say their cases rest on Big Oil’s deception about the harm its products would cause, giving them a foothold under state law to seek damages.

The jurisdictional battle, which more federal appeals courts are likely to rule on this year, will have massive implications for whether the climate lawsuits proceed to local jury trials. If they do, it would set up a high-stakes showdown over the still uncertain territory of legal accountability for climate change—with billions of dollars on the line.

Several states and industry groups have weighed in to support the oil companies, arguing that rulings against them could devastate the industry and make energy more expensive.

“If it’s in federal court, (the oil companies) win,” said Hannah Wiseman, a professor of law at Penn State University’s College of Earth and Mineral Sciences. “These cities are wise to the precedent, and they’ve made clear they’re raising issues of state tort law and not arguing for federal climate policy. They’re doing a good job of that, and it’s hard to predict how the courts will ultimately come out.”

The governments suing the oil industry come from regions facing sea level rise, wildfires, drought, flooding and severe weather. They cite extensive news reporting—including investigations from the Los Angeles Times, Inside Climate News and The Guardian—that shows oil companies understood the dangers of climate change decades ago but led campaigns to undermine the scientific consensus that their products were contributing to a growing crisis.

“By the ’70s, (oil companies) knew that a lack of action on moving away from fossil fuels would cause dramatic changes to the climate,” Brockett said. “Meanwhile, the burden for repairing the damage falls on local communities, and we don’t have the financial wherewithal to bear that burden.”

Backers of the lawsuits compare them to landmark cases against tobacco and opioid manufacturers, which resulted in multibillion-dollar settlements over the public health crises fueled by their products and business practices.

“They’re just saying, ‘You violated state law, because you deceived us about what you knew about your products in order to sell more of them,'” said Bob Percival, director of the University of Maryland’s environmental law program. “The oil companies are desperate to avoid a public trial that would focus attention on what they knew, when they knew it and how they tried to deceive the public.”

The cases mark an unprecedented attempt to assert legal accountability for climate change, a crisis with worldwide causes and consequences.

“The fact that it’s a global phenomenon is obviously the thing that distinguishes these tort actions from any case we’ve seen before,” said Pat Parenteau, a professor of environmental law at Vermont Law School, who also serves in an informal advisory group that supports some of the governments’ cases.

The oil companies named in the cases argue that federal energy and pollution policies should preempt state claims. Exxon Mobil and Suncor have contended in court filings in the Colorado lawsuit that they followed federal regulations on drilling, refining and distributing fossil fuels. The companies also assert that the lawsuits are backdoor attempts to establish climate policy through the courts, since Congress has failed to take meaningful action.

“On jurisdictional matters, climate change is a national issue that requires a federal solution, not a patchwork of various state-based rulings,” said William Allison, spokesperson for Energy In Depth, a research and public outreach project of the Independent Petroleum Association of America, a trade group.

Major companies facing the lawsuits—BP, Chevron, Exxon Mobil, Suncor, the American Petroleum Institute, Koch Industries and Shell—did not respond to Stateline’s requests for comment.

Supporters of the lawsuits say the cases aren’t about enforcing or enacting policies to reduce carbon emissions, but rather about seeking accountability for what they say are decades of dishonesty that contributed to political inaction on climate change.

Many of the cases have been through years of legal wrangling, and the current battle centers on whether they should be heard in state or federal court. Those backing the lawsuits say local juries should hear the cases.

“These cases, which are fundamentally about local injuries to communities, should be heard in state court,” said Marco Simons, general counsel with EarthRights International, which is representing the Colorado communities. “Our cases are not about stopping climate change writ large or broader policy issues. They’re about paying for damages suffered by these communities.”

But some states have weighed in to argue that the cases belong in federal court. For example, Indiana has filed multiple amicus briefs in favor of oil companies, including a recent filing with 13 states in the case brought by Baltimore.

“These claims are displaced by the existing federal regulatory scheme, which tells us the limits in advance on extraction, refinement and use of fossil fuels,” Tom Fisher, Indiana’s solicitor general, said in an interview. “If a court in California decides that Exxon and Chevron are responsible under public nuisance theory for causing global climate change and that requires an injunction to limit their output, that’s obviously going to affect Indiana and other states.”

Some business groups, including the Manufacturers’ Accountability Project, an arm of the National Association of Manufacturers that fights climate litigation, also have urged federal courts to take jurisdiction.

“Climate policy is federal and regulatory in nature—not one that can be decided by state courts,” Phil Goldberg, the project’s special counsel, wrote in an email to Stateline.

The National League of Cities, which advocates for municipal governments, takes a different view.

“This is really about federalism principles and where cases should be heard if there’s a local harm,” said Carolyn Berndt, the group’s legislative director for sustainability. “The local harm in this case happens to be climate change, and the right court for this is state court.”

Although federal judges mostly have ruled that the cases belong in state court, a U.S. Supreme Court ruling last May forced federal appeals courts to reevaluate those decisions because they hadn’t considered all the energy companies’ arguments.

This February, the 10th U.S. Circuit Court of Appeals ruled that the case filed by the Colorado municipalities would remain in state court, the first decision under the new Supreme Court guidelines. Last week, the 4th Circuit ruled that Baltimore’s case against oil companies also belonged in state court.

Several other circuit courts have yet to rule under the new guidelines.

“This is an important year,” said Richard Wiles, president of the Center for Climate Integrity, a nonprofit that supports communities that are taking on oil companies. “If these cases end up in state court, that’s a really good sign. If one of the circuits goes (the oil companies’) way, that could create grounds for an appeal to the Supreme Court.”

While several federal appeals court decisions await, some cases are moving ahead. Last month, a Hawaii Circuit Court judge ruled that a lawsuit filed by Honolulu could proceed to trial even as the jurisdictional issues are still being settled. The case could be the first to reach the discovery phase, an outcome advocates say energy companies have fought tooth-and-nail to avoid.

“They absolutely do not want it to get that far,” said Tommy Waters, chair of the Honolulu City Council. “What are they hiding?”

Waters said Honolulu is facing billions in damages from sea level rise alone, and it also requires expensive upgrades to its stormwater infrastructure to handle extreme precipitation.

“Our roads are falling into the ocean, homes are falling into the ocean, our beaches are disappearing,” he said. “We simply can’t afford it.”

Another case, filed by the state of Massachusetts against Exxon Mobil, also is moving toward discovery. That lawsuit, like most of the cases brought by state attorneys general, focuses on consumer fraud violations. Such lawsuits seek civil penalties, rather than restitution for the costs of climate mitigation.

If the local governments prove their cases against the oil companies, the implications would be massive. Courts may have to determine the extent to which a given company is responsible for the climate damages in a particular region.

“Science has made great strides in being able to attribute what percentage of temperature rise and what impacts are associated with a particular company’s emissions,” said Percival, the University of Maryland professor. “There are now some really distinguished experts who can testify about how to apportion the harm.”

And if some cities and counties are successful, advocates expect a deluge of others to file suits.

“If these cases are ruled in favor of the plaintiffs, then every city in the country could follow suit,” said Wiles of the Center for Climate Integrity. “There isn’t a city budget out there that couldn’t use help from the oil companies for their climate-driven adaptation costs.”

Backers of the lawsuits acknowledge that the costs of dealing with climate change nationwide are far more than the oil companies could bear.

“If these cases all go to their logical extreme, [the oil companies] all go bankrupt,” said Parenteau, the Vermont Law School professor. “They should.”

Others argue that outcome is why the cases should be dropped.

“We choose to use energy, which is mostly fossil fuel, because it makes our lives better,” said Wayne Winegarden, a senior fellow at the Pacific Research Institute, a California-based think tank that advocates for free market principles and is supported in part by oil industry-affiliated groups. “Imagine they win $100 billion in one of the suits. That becomes a per-barrel tax that gets passed on to consumers.”

New method for tracking the sources of diamonds

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New method for tracking the sources of diamonds

A technique for identifying the sources of diamonds without the use of clues such as the presence of specific inclusions will be reported on Wednesday, Nov. 4, in a presentation by Catherine McManus, Chief Scientist at Materialytics, LLC, at The Geological Society of America’s Annual Meeting in Baltimore, Maryland, USA. The new testing method produced results with average accuracy around 98%.

“The report is unique because all of the 330 test samples used are of gem quality, making this diamond provenance study relevant not only to geologists but also to consumers by providing a scientific verification in support of conflict-free trade,” said McManus.

Materialytics has extensively studied industrial ceramics, metal alloys, and electronic components to identify counterfeits and improve quality control. Materials such as tin, tungsten, tantalum, gold, as well as gemstones such as emeralds, have been studied for origins. However, studies on gem-quality diamonds have historically presented a challenge because of their chemical simplicity.

Co-author Nancy McMillan, of New Mexico State University, observed that “one of our major findings is that the high success rates are not due to inclusions in the diamonds, but rather to signals from the carbon itself. That is significant, because it means that this method of analysis is applicable to all diamonds.”

The implications of this research appear to be far reaching.

What is granite rock and how is it formed?

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What is granite rock and how is it formed?

What is Granite?

Granite is a common type of granular and phaneritic felsic intrusive igneous rock. Granites, depending on their mineralogy, can be predominantly white, pink or gray in colour. In reference to the coarse-grained structure of such a holocrystalline rock, the word “granite” comes from the Latin granum, a grain. Strictly speaking, granite is an igneous rock with a volume of between 20% and 60% and at least 35% of the total feldspar consisting of alkali feldspar, although the term “granite” is commonly used to refer to a wider range of coarse-grained igneous rocks with quartz and feldspar.

The term “granite” is used for granite and a group of intrusive igneous rocks with similar textures and slight variations in composition and origin. These rocks consist mainly of feldspar, quartz, mica, and amphibole minerals, forming an interlocking, somewhat equigranular feldspar and quartz matrix with dispersed darker biotite mica and amphibole (often hornblende) peppering the lighter minerals.

Granite is almost always massive, hard and tough (i.e. without any internal structures). Throughout human history, these properties have made granite a widespread building stone. The average granite density ranges from 2.65 to 2.75 g / cm3 (165 to 172 lb / cu ft), its compressive strength is usually above 200 MPa, and its viscosity near STP is 3–6·1019 Pa·s.

How is granite formed?

Granite is more common in continental crust than in oceanic crust and has a felsic composition. They are crystallized by felsic melts that are less dense than mafia rocks and therefore tend to ascend to the surface. Mafic rocks, on the other hand, either basalts or gabbros, once metamorphosed at eclogite facies, tend to sink under the Moho into the mantle.

Uses of Granite

Granite has many uses as well as interior / exterior design in the construction. It is popular throughout the world and widely used for architectural design. The following are some of the most commonly used granite products:

  1. Granite flooring tiles
  2. Granite wall tiles
  3. Granite slabs for vanity and counter tops, feature walls and kitchen islands
  4. Granite monuments
  5. Granite tombstones
  6. Granite cobbles
  7. Granite paving stones

Earliest evidence of Maya divination calendar discovered in ancient temple

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Earliest evidence of Maya divination calendar discovered in ancient temple

Archaeologists in Guatemala have discovered the oldest evidence of the Maya calendar on record: two mural fragments that, when pieced together, reveal a notation known as “7 deer,” a new study finds.

The two “7 deer” fragments date to between 300 B.C. and 200 B.C., according to radiocarbon dating done by the research team. This early date indicates that this Maya divination calendar, which was also used by other pre-Columbian cultures in Mesoamerica, such as the Aztecs, has been in continuous use for at least 2,300 years, as it is still followed today by modern Maya, the researchers said. (Notably, this is not the Long Count calendar that some people used to suggest the world was going to end in 2012.)

“It’s the one calendar that survives all the conquests and the civil war in Guatemala,” the latter of which was waged from 1960 to 1996, study first author David Stuart, the Schele professor of Mesoamerican art and writing at the University of Texas at Austin, told Live Science. “The Maya of today in many communities have kept it as a way of connecting to their ideas of fate and how people relate to the world around them. It’s not a revival. It’s actually a preservation of the calendar.”

The researchers found the mural fragments at the archaeological site of San Bartolo, northeast of the ancient Maya city of Tikal. Stuart was part of the team that discovered San Bartolo in 2001. “It’s in the remote jungles of northern Guatemala” and famous for its Maya murals dating to the Late Preclassic period (400 B.C. to A.D. 200), he said.

The murals at San Bartolo are in a massive complex known as Las Pinturas, which the Maya built over hundreds of years. Every so often, the Maya would build over an old complex, constructing larger and more impressive structures. As a result, Las Pinturas is layered like an onion. If archaeologists tunnel into its inner layers, they can find earlier structures and murals, Stuart said.

The researchers collected ancient organic material, such as charcoal, within the layer where the mural fragments were discovered. By radiocarbon-dating these fragments, they could estimate when the murals were created.

However, these murals weren’t in one piece. In total, the team discovered about 7,000 fragments from various murals. Of this colossal collection, the team analyzed 11 wall fragments, discovered between 2002 and 2012, with radiocarbon dating. These included the two pieces that formed the “7 deer” notation, which includes a glyph, or image of a deer under the Maya symbol for the number seven (a horizontal line with two dots over it).

Four Maya calendars

The Maya had four calendars, as “they were very interested in timekeeping,” Stuart said. “They had very elaborate and elegant ways of tracking time.”

One is the sacred divination calendar, or Tzolk’in, from which this “7 deer” notation originates. This calendar has 260 days consisting of a combination of 13 numbers and 20 days that have different signs (like deer). 

The 260 days don’t make up a year, however. Rather, it’s a cycle similar to the seven-day week. The notation “7 deer” doesn’t give you a date; it doesn’t tell you the season or year in which something happened. “It’s like saying Napoleon invaded Russia on a Wednesday,” Marcello Canuto, director of the Middle American Research Institute at Tulane University, who wasn’t involved with the study, told Live Science.

Today, the 260-day cycle in the Tzolk’in calendar is used for soothsaying and ceremonial record keeping, Stuart said. “There are date keepers, as they’re called, in Guatemala today,” Stuart said. “If you said the day is 7 deer, they would go, ‘Oh yeah, 7 deer, that means this, this and this.'”

The other Maya calendars are the Haab’, a solar calendar that lasts 365 days but doesn’t account for a leap year; a lunar calendar; and the Long Count calendar, which tracks major time cycles and caused a lot of brouhaha in when some people (mistakenly) thought it was foretelling the end of the world in 2012, Live Science previously reported.

“[I remember] all that nonsense back in 2012 about the end of a cycle,” Stuart said. “Everyone was saying, ‘It’s the end of the calendar.’ But no, they didn’t understand there was yet another cycle after that.”

There are other calendar notations that might be older than the newly described 7-deer finding, but these artifacts are challenging to date because they were carved into stone (which does not hold any radioactive carbon that can be dated). Moreover, these carved stones were possibly moved around, meaning a date from the site might not reflect the date of these calendars, Stuart said. For instance, a proposed Tzolk’in calendar found in Oaxaca Valley, Mexico has dates ranging from 700 B.C. to 100 B.C., according to several studies.

When these four types of calendars are taken into account, this “7 deer” notation is the “earliest evidence of any Maya calendar, possibly [the] earliest securely dated evidence anywhere in Mesoamerica,” Stuart said. 

Surprising deer

The archaeologists were surprised to find the deer glyph. Later Maya Tzolk’in notations almost always write out the word for deer rather than drawing a glyph of the animal, Stuart said. In effect, these fragments might be evidence of an early stage of Maya script, he said.

“We speculate a little bit in the article that it may be that this is an early phase of the writing system where they haven’t quite established the norms that we’re used to,” Stuart said. He added that it’s unclear where in Mesoamerica this calendrical system began.

These two lines of evidence help tie everything together, Canuto noted. “The text seems to suggest something really archaic, and then the radiocarbon and the context of the dating seems to support that,” he said.

The study is “meticulously done,” Walter Witschey, a retired research professor of anthropology and geography at Longwood University in Virginia and a research fellow at the Middle American Research Institute, told Live Science in an email. The finding is “evidence for the earliest known calendar notation from the Maya region,” he said.

The study was published online Wednesday (April 13) in the journal Science Advances.

A dusty, compact object bridging galaxies and quasars at cosmic dawn

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A dusty, compact object bridging galaxies and quasars at cosmic dawn

An international effort led by astrophysicists at the Niels Bohr Institute, University of Copenhagen, and the Technical University of Denmark has identified a distant object with properties that lie between those of a galaxy and those of a so-called quasar.

The object can be seen as the ancestor of a supermassive black hole, and it was born relatively soon after the Big Bang. Simulations had indicated that such objects should exist, but this is the first actual discovery.

“The discovered object connects two rare populations of celestial objects, namely dusty starbursts and luminous quasars, and thereby provides a new avenue toward understanding the rapid growth of supermassive black holes in the early universe,” says Seiji Fujimoto, a postdoctoral fellow based at the Niels Bohr Institute, University of Copenhagen.

The discovery can be attributed to the Hubble Space Telescope operated jointly by ESA and NASA. With its location in space, the telescope can gaze further into the depths of the universe than would have been the case on the ground. And in astronomy, looking further equals being able to observe phenomena which took place at earlier cosmic periods, since light and other types of radiation travel longer to reach us.

The newly found object—named GNz7q by the team—was born 750 million years after the Big Bang, which is generally accepted as the beginning of the universe as we know it. Since the Big Bang occurred about 13.8 billion years ago, GNz7q origins in an epoch known as “cosmic dawn.”

The mystery of supermassive black holes

The discovery is linked to a specific type of quasars. Quasars, also known as quasi-stellar objects, are extremely luminous objects. Images from Hubble and other advanced telescopes have revealed that quasars occur in the centers of galaxies. The host galaxy for GNz7q is an intensely star-forming galaxy, forming stars at a rate 1,600 times faster than our own galaxy, the Milky Way. The stars, in turn, create and heat cosmic dust, making it glow in infrared to the extent that GNz7q’s host is more luminous in dust emission than any other known object at this period of the cosmic dawn.

In the most recent years it has transpired, that luminous quasars are powered by supermassive black holes, with masses ranging from millions to tens of billions of solar masses, surrounded by vast amounts of gas. As the gas falls towards the black hole, it will heat up due to friction which provides the enormous luminous effect.

“Understanding how supermassive black holes form and grow in the early universe has become a major mystery. Theorists have predicted that these black holes undergo an early phase of rapid growth: a dust-reddened compact object emerges from a heavily dust-obscured starburst galaxy, then transitions to an unobscured luminous compact object by expelling the surrounding gas and dust,” explains Associate Professor Gabriel Brammer, Niels Bohr Institute. “Although luminous quasars had already been found even at the earliest epochs of the universe, the transition phase of rapid growth of both the black hole and its star-bursting host had not been found at similar epochs. Moreover, the observed properties are in excellent agreement with the theoretical simulations and suggest that GNz7q is the first example of the transitioning, rapid growth phase of black holes at the dusty star core, an ancestor of the later supermassive black hole.”

Both Seiji Fujimoto and Gabriel Brammer are part of the cosmic dawn Center (DAWN), a collaboration between Niels Bohr Institute and DTU Space.

Breaking news from the dawn of the universe
The object, which is referred to as GNz7q, is shown here in the centre of the image of the Hubble GOODS-North field. Credit: NASA, ESA, G. Illingworth (University of California, Santa Cruz), P. Oesch (University of California, Santa Cruz; Yale University), R. Bouwens and I. Labbé (Leiden University), and the Science Team, S. Fujimoto et al. (Cosmic Dawn Center [DAWN] and University of Copenhagen)

Hiding in plain sight

Curiously, GNz7q was found at the center of an intensely studied sky field known as the Hubble GOODS North field.

“This shows how big discoveries can often be hidden right in front of you,” Gabriel Brammer says.

Finding GNz7q hiding in plain sight was only possible thanks to the uniquely detailed, multi-wavelength datasets available for GOODS North. Without the richness of data, the object would have been easy to overlook, as it lacks the distinguishing features for quasars in the early universe.

“It’s unlikely that discovering GNz7q within the relatively small GOODS-N survey was just “dumb luck,” but rather that the prevalence of such sources may in fact be significantly higher than previously thought,” Brammer adds.

The team now hopes to systematically search for similar objects using dedicated high-resolution surveys and to take advantage of the NASA/ESA/CSA James Webb Space Telescope.

“Fully characterizing these objects and probing their evolution and underlying physics in much greater detail will become possible with the James Webb Telescope. Once in regular operation, Webb will have the power to decisively determine how common these rapidly growing black holes truly are,” Seiji Fujimoto says.

A paper on the discovery of GNz7q, “A dusty compact object bridging galaxies and quasars at cosmic dawn,” is published in the online edition of Nature on April 13, 2022.

More information: Seiji Fujimoto, A dusty compact object bridging galaxies and quasars at cosmic dawn, Nature (2022). DOI: 10.1038/s41586-022-04454-1. www.nature.com/articles/s41586-022-04454-1
Journal information: Nature.

Team behind discovery of planet with three stars retracts their article

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Team behind discovery of planet with three stars retracts their article

An international team of researchers who published a paper in the journal Science in 2016 describing their discovery of an exoplanet with three stars, has now retracted that paper.

In their original paper, the team described their work with direct imaging technology to study the triple-star system HD 131399. They spotted what they believed to be an exoplanet approximately four times the size of Jupiter. They also noted its apparent odd orbital system—the planet appeared to orbit just one of the stars while the other two stars were farther away.

Subsequent to the publishing of the paper, in 2017, another international team of researchers found evidence suggesting that the planet was not a planet after all—the data observed the year before, they claimed, was from a background object, perhaps a dwarf star. They further noted in their paper published in The Astronomical Journal, that the object was much more likely to be something moving unusually fast in the background in a path that coincided with star system HD 131399.

That finding led the original team to take another look at their earlier work and then to observe star system HD 131399 over an extended period of time. This allowed them to capture imagery of the star system in motion. They discovered “a clear parallax difference between the object and HD 131399″—confirmation that the light from what they had thought in 2016 was a planet was actually coming from much farther away than light from the stars in the system—ruling out the possibility that the light was from a planet in that system. It was instead most certainly from something much farther away in the distant background.

The researchers have suggested to members of the press that their work highlights the risk in making assumptions about stationary backgrounds in star systems, and that it is their hope that their experience will help to improve astronomy. All of the authors of the original paper have agreed to having their paper retracted.

More information: Kevin Wagner et al, Retraction, Science (2022). DOI: 10.1126/science.abq1709
Journal information: Astronomical Journal , Science.

Chinese astronauts return to Earth after six months on space station

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Chinese astronauts return to Earth after six months on space station

Three Chinese astronauts returned to Earth on Saturday after 183 days in space, ending China’s longest crewed mission as it continues its quest to become a major space power.

The Shenzhou-13 spacecraft was the latest mission in Beijing’s drive to rival the United States, after landing a rover on Mars and sending probes to the Moon.

Live footage from state broadcaster CCTV showed the capsule landing in a cloud of dust, with ground crew who had kept clear of the landing site rushing in helicopters to reach the capsule.

The two men and one woman — Zhai Zhigang, Ye Guangfu and Wang Yaping — returned to Earth shortly before 10 am Beijing time (0200 GMT), after six months aboard the Tianhe core module of China’s Tiangong space station.

Ground crew applauded as the astronauts each took turns to report that they were in good physical condition.

Zhai was the first to emerge from the capsule roughly 45 minutes after the landing, waving and grinning at cameras as he was lifted by ground crew into a specially designed chair before being bundled into a blanket.

“I’m proud of our heroic country,” Zhai said in an interview with CCTV shortly after leaving the capsule. “I feel extremely good.”

The trio originally launched in the Shenzhou-13 from China’s northwestern Gobi Desert last October, as the second of four crewed missions during 2021-2022 sent to assemble the country’s first permanent space station — Tiangong, which means “heavenly palace.”

Wang became the first Chinese woman to spacewalk last November, as she and her colleague Zhai installed space station equipment during a six-hour stint.

Mission commander Zhai, 55, is a former fighter pilot who performed China’s first spacewalk in 2008, while Ye is a People’s Liberation Army pilot.

The trio have completed two spacewalks, carried out numerous scientific experiments, set up equipment and tested technologies for future construction during their time in orbit.

The astronauts spent the past few weeks tidying up and preparing the cabin facilities and equipment for the crew of the incoming Shenzhou-14, expected to be launched in the coming months.

China’s previous record spaceflight mission length was set by last year’s Shenzhou-12 deployment, which lasted 92 days.

Six months will become the normal astronaut residence period aboard the Chinese space station, according to state broadcaster CCTV.

Space race
The world’s second-largest economy has poured billions into its military-run space programme, with hopes of having a permanently crewed space station by 2022 and eventually sending humans to the Moon.

The country has come a long way in catching up with the United States and Russia, whose astronauts and cosmonauts have decades of experience in space exploration.

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