Science: Asteroid that wiped out the dinosaurs hit Earth during northern spring, scientists argue

The asteroid impact that wiped out most dinosaurs may have taken place during the Northern Hemisphere’s spring or early summer, according to new research on the infamous mass extinction.

The new research hinges on a site called Tanis, located in North Dakota, that an overlapping group of scientists announced in 2019. That work argued that the site’s fossilized wildlife died within hours of a large asteroid slamming into the Yucatán peninsula 66 million years ago in what is today Mexico. (Notably, the bulk of the fossils buried at Tanis did not belong to dinosaurs; most come from fishes.)

In the new paper, the researchers argue that those fish fossils also suggest that the impact occurred while the Northern Hemisphere was in spring or early summer, potentially making the event still more devastating to life in that hemisphere.

"This project has been a huge undertaking but well worth it," Robert DePalma, the lead author of both research papers and a graduate student in paleontology at the University of Manchester, said in a university statement.

The extinction itself is famous: The most recent of the five mass die-offs that paleontologists have identified in the fossil record, the extinction marked the end of the Cretaceous period 66 million years ago and wiped out about 75% of the species that lived on Earth at the time.

Scientists continue to debate whether the asteroid impact and its consequences were solely responsible for the extinction. Some argue that massive volcanic eruptions that happened at about the same time may have done the job, or that only both catastrophes in tandem could have made such a mark. Either way, the impact had global consequences.

The 2019 paper hailing the North Dakota site’s fossils as a legacy of the impact was greeted with some skepticism, in part because a high-profile magazine story broke the news with scant scientific details; according to reporting at the time by Science, some paleontologists also expressed concerns about DePalma’s professional practices.

But Tanis is tantalizing because, if the research is correct, it would mark the first site where scientists can see the direct consequences of the asteroid impact on life. (Geologists have studied the Chicxulub crater left behind, of course, but the whole asteroid impact situation really did a number on the local fossil record of the period.)

DePalma and his colleagues wanted to determine whether they could date the Tanis fossils to a specific part of the year. Many of the fossils at the site come from paddlefish and sturgeon species at a range of ages.

Fish bones, coincidentally, display the same type of pattern as the annual rings of trees. Fish bones grow a dark layer in the spring and summer, when the animals have plenty to eat and grow faster; in the fall and winter, a lighter band forms. These two bands also sport different ratios of the chemical flavors of carbon that scientists can distinguish in the lab.

When DePalma and his colleagues looked at the bones this way, they found that the most recent layer, found on the outside of the bones, had formed during a season of plenty.

The researchers also used a synchrotron to analyze trace metals found in the fossils, which scientists can use to determine how developed the animal was when it died. That analysis found that there were both adult and juvenile fish at the site, also suggesting a spring or early summer cataclysm, the researchers determined.

All this makes sense, the scientists argue. Modern species of sturgeon migrate between saltwater in the winter and freshwater in the spring and summer, and Tanis was a freshwater site. The researchers found that insect damage preserved in fossilized leaves and fossils of adult mayflies during the catastrophe also match the seasonal timing they suggest.

"Animal behavior can be a pretty powerful tool," Loren Gurche, a co-author on the study and a graduate student at the University of Kansas, said in the statement. "They all matched up."

The scientists even suggest that a spring impact may have triggered more extinctions in the Northern Hemisphere than in the southern. Species in areas of the Northern Hemisphere with distinct seasonal variations built into their lifestyle, the authors wrote in the paper, would have "vulnerabilities inherent to this time span, which was a period of growth and reproduction for many animals and plants."

Had the asteroid hit Earth six months earlier or later than it did, would more dinosaurs have survived? Would mammals have come to rule the world? There’s no way to know, of course.

"Extinction can mark the end of a dynasty, but we must not forget that our own species might not have evolved if it weren’t for the impact and the timing of events that saw the end of the dinosaurs," DePalma said.

The research is described in a paper published Wednesday (Dec. 8) in the journal Scientific Reports.


Russian cosmonaut Oleg Kononenko sets a new world record for the most time spent in space

A Russian cosmonaut has set a new record for the most time in space after spending nearly two and a half years cumulatively on the ISS.

Russian cosmonaut Oleg Kononenko has broken the world record for the most cumulative time spent in space, Russia’s space agency Roscosmos reported on Sunday.

The 59-year-old has now spent more than 878 days and 12 hours in space, surpassing fellow Russian Gennady Padalka, who set the previous record of 878 days, 11 hours, 29 minutes, and 48 seconds in 2015.

Kononenko has made five journeys to the International Space Station (ISS), dating back to 2008.

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Speaking with Russian state news agency TASS, the engineer said that each trip to the ISS required careful preparation due to the station’s constant upgrades – but that life as a cosmonaut was a childhood dream come true.

"I fly into space to do what I love, not to set records. I’ve dreamt of and aspired to become a cosmonaut since I was a child. That interest – the opportunity to fly into space, to live and work in orbit – motivates me to continue flying," he told TASS.

Kononenko’s current trip to the ISS began on September 15, 2023, when he launched alongside NASA astronaut Loral O’Hara and Roscosmos compatriot Nikolai Chub.

By the end of this expedition, the cosmonaut is expected to become the first person to accumulate 1,000 days in space.

The International Space Station is one of the few areas in which the United States and Russia still cooperate closely following Moscow’s invasion of Ukraine in February 2022.

Roscosmos announced in December that its cross-flight programme with NASA transporting astronauts to the ISS had been extended until 2025.


Technology & Engineering: Largest ever fully electric concept plane could take to the skies by 2033

[Electric planes might be a better idea than electric cars. I'm not fully sure, but I would think so. Jan]

A startup has unveiled its design for a fully electric passenger jet that can seat up to 90 passengers, with plans to launch it within the next 10 years.

The E9X concept, designed by the Dutch company Elysian, is a battery-powered plane that can fly up to 500 miles (800 kilometers) on a single charge based on a theoretical battery pack of 360 watt-hours per kilogram — the standard measure of battery density. By contrast, a Tesla battery has a density of between 272 and 296 Wh/kg according to Inside EVs. With future improvements, the startup hopes to boost the plane’s range up to 620 miles (1,000 km).

The design of the E9X, and the core technology that powers it, is based on a collaboration with researchers at the Delft University of Technology, which produced two papers published Jan. 4 in the journal American Institute of Aeronautics and Astronautics (AIAA).

The first paper focused on redefining assumptions around existing battery technology. Most literature suggests battery-electric aircraft are only feasible for shorter-range trips of up to 250 miles (400 km) with up to 19 passengers on board. As a result, most real-world efforts have focused on designing regional or inter-city electric aircraft.

These widely used assumptions likely stem from much earlier expectations and technological constraints, Simay Akar, Institute of Electrical and Electronics Engineers senior member and the CEO and founder of AK Energy Consulting told Live Science.

In the paper, the study authors suggest that advances in battery technology mean that larger aircraft can house denser batteries. Meeting the design specifications, however, can’t be done with commercially available technology; it "would depend on breakthroughs in battery energy density, weight, and efficiency to achieve such ambitious goals," Akar said.

The study also argues that planes can be designed to be more aerodynamically efficient than previously thought — meaning they could generate more lift without increasing drag.

They performed calculations on high-level estimates from previous aircraft to show there’s a "design space" where both energy density and aerodynamic efficiency can "reach significantly higher values than often assumed."

They validated these assumptions by making more detailed estimates that incorporated each component of a plane — including onboard equipment and systems — to show that a hypothetical plane could fly once the breakthroughs are made.

The second paper outlined the rough dimensions of the 90-seater E9X aircraft, which would include batteries integrated into the wings, a low-wing configuration, as well as folding wingtips. The plane they designed has an energy consumption of 167 Wh per passenger-kilometer, meaning it takes 167 watt-hours to ferry each passenger a kilometer. This equates to "an environmental impact well below" kerosene, electro-fuelled sustainable aviation fuel (eSAF), or hydrogen-based alternatives. The authors added this environmental impact is comparable to land-based modes of transport, such as today’s electric cars.

“High density battery technology is one of the challenges at this moment, because scaling up production and further improving density remain crucial for widespread adoption," said Akar. "360 Wh/kg energy density is a significant leap from current battery technology and crucial for an electric plane’s range. Also, ground infrastructure and regulations still need to adapt to accommodate electric aircraft prior to the targeted timeline.”

The E9X won’t be the first electric passenger aircraft to take flight, if and when it does in 2033. The first electric passenger plane was Eviation Alice, designed to accommodate up to nine passengers and two crew — with its manufacturer first testing a prototype in September 2022 ahead of a target date of 2027 for full production, company representatives said. It has a range of approximately 250 nautical miles (approximately 288 miles or 463 km).

Whether or not the company hits this date remains to be seen, but Eviation has struck agreements with carriers to ship the plane in the future — including a written agreement with the European regional airline flyVbird to supply 25 aircraft, with an option for a further 25 in the future.


The Fossils I saw here in South Africa – Amazing Tree Fossils and others

Here in SA, I once went to a farm where there were small footprints in rock from the dinosaur age. It was amazing to see the footprints and how the small lizards’ tails had dragged through what was once clearly some mud by a river or lake. For me the most amazing thing I saw was on the coast near margate where you could see fossilized trees near the beach. Trees that used to exist, but which are now solid rock. I found it amazing, being close up and looking at it. I took many photos. You also get "fossil negatives" where the original thing died and rotted away (e.g. tree trunk) and then rock formed around it. The trees blew my mind – you could see them fallen down and you could even see tree rings. I have the photos.

But, one of the greatest places on earth for fossils is in the semi-desert known as the Kalahari. That used to be a sea bed. some of the wildest craziest fossils ever found were found there including impossible fossils like jelly fish in what is now solid rock. (My suspicion is that this was created through very high speed, intensive catastrophic events).

VERY IMPORTANT SCIENTIFIC EXPERIMENT: Scientists closer to finding quantum gravity theory after measuring gravity on microscopic level

[I can't over stress the critical importance of this. This is what we really need and this will lead to unbelievable things. With this we are heading towards the greatest breakthrough since nuclear physics. This is even bigger than that. With this, we can head across the universe. Once we figure out how gravity actually works … insane things will be possible. This is something I've mentioned many times in the past. We need to know HOW gravity actually works. This is the first true breakthrough ever. Jan]

Scientists are a step closer to unraveling the mysterious forces of the universe after working out how to measure gravity on a microscopic level.

Experts have never fully understood how the force that was discovered by Isaac Newton works in the tiny quantum world. Even Einstein was baffled by quantum gravity and, in his theory of general relativity, said there is no realistic experiment that could show a quantum version of gravity.

But now physicists at the University of Southampton, working with scientists in Europe, have successfully detected a weak gravitational pull on a tiny particle using a new technique.

They claim it could pave the way to finding the elusive quantum gravity theory.

The experiment, published in Science Advances, used levitating magnets to detect gravity on microscopic particles—small enough to border on the quantum realm.

Lead author Tim Fuchs, from the University of Southampton, said the results could help experts find the missing puzzle piece in our picture of reality.

He added, "For a century, scientists have tried and failed to understand how gravity and quantum mechanics work together. Now we have successfully measured gravitational signals at a smallest mass ever recorded, it means we are one step closer to finally realizing how it works in tandem.

"From here we will start scaling the source down using this technique until we reach the quantum world on both sides. By understanding quantum gravity, we could solve some of the mysteries of our universe—like how it began, what happens inside black holes, or uniting all forces into one big theory."

The rules of the quantum realm are still not fully understood by science—but it is believed that particles and forces at a microscopic scale interact differently than regular-sized objects.

Academics from Southampton conducted the experiment with scientists at Leiden University in the Netherlands and the Institute for Photonics and Nanotechnologies in Italy.

Their study used a sophisticated setup involving superconducting devices, known as traps, with magnetic fields, sensitive detectors and advanced vibration isolation. It measured a weak pull, just 30aN, on a tiny particle 0.43mg in size by levitating it in freezing temperatures a hundredth of a degree above absolute zero—about –273 degrees Celsius.

The results open the door for future experiments between even smaller objects and forces, said Professor of Physics Hendrik Ulbricht also at the University of Southampton.

He added, "We are pushing the boundaries of science that could lead to new discoveries about gravity and the quantum world.

"Our new technique that uses extremely cold temperatures and devices to isolate vibration of the particle will likely prove the way forward for measuring quantum gravity.

"Unraveling these mysteries will help us unlock more secrets about the universe’s very fabric, from the tiniest particles to the grandest cosmic structures."

More information: Tim Fuchs et al, Measuring gravity with milligram levitated masses, Science Advances (2024). DOI: 10.1126/sciadv.adk2949.

Journal information: Science Advances


Scientists have a new way to find oceans — and possible alien life — on distant planets

Searching for liquid water on exoplanets is the key to finding life among the stars, and now, scientists have proposed a new strategy that might improve the chances of finding it.

In the new study, published Dec. 28 in the journal Nature Astronomy, researchers hypothesized that if the atmosphere of an exoplanet has less CO2 than its neighbors, there may be vast quantities of water on its surface — or even life.

Currently, finding liquid water on planets outside the solar system is a major challenge. Of the 5,000 or so exoplanets we’ve discovered, liquid water hasn’t been confirmed on any. The best scientists can do is detect traces of water in exoplanet atmospheres and determine whether planets could theoretically support water in the liquid state.

"We know that initially, the Earth’s atmosphere used to be mostly CO2, but then the carbon dissolved into the ocean and made the planet able to support life for the last four billion years or so," study co-lead author Amaury Triaud, professor of exoplanetology at the University of Birmingham in the U.K., said in a statement.

Once carbon is dissolved in the oceans, tectonic activity then locks it away in Earth’s crust, creating an effective carbon sink. This is partly why our planet has significantly lower CO2 levels compared with our neighbors — Earth’s atmosphere is around 0.04% CO2, whereas the atmospheres on Venus and Mars are both over 95% CO2.

If scientists observe a similarly low-carbon atmosphere on an exoplanet, it could indicate the presence of vast oceans similar to our own, the researchers said.

Looking for CO2 is easier than finding liquid water. CO2 absorbs infrared radiation very well, meaning it produces a strong signal that scientists can detect.

It’s also possible to perform this technique with existing telescopes, such as the James Webb Space Telescope (JWST). Ground-based observations should also be possible because of the specific wavelength CO2 is measured at — whereas Earth’s atmosphere can torpedo experiments at other wavelengths by partially absorbing the signals.

"It’s a really nice way of doing this. And it’s also not going to involve a massive investment of telescope time, which is really important because that’s extremely precious to our community," said Sarah Casewell, a lecturer in the school of physics and astronomy at the University of Leicester in the U.K., who wasn’t involved in the research.

Tantalizingly, another scenario could contribute to an atmosphere low in carbon: life itself. The main ways life on our planet captures carbon are through photosynthesis and making shells, and around 20% of all carbon capture on Earth is caused by biological processes.

"Despite much early hopes, most of our colleagues had eventually come to the conclusion that major telescopes like the JWST would not be able to detect life on exoplanets. Our work brings new hope," study co-lead author Julien de Wit, assistant professor of planetary sciences at the Massachusetts Institute of Technology, said in the statement. "By leveraging the signature of carbon dioxide, not only can we infer the presence of liquid water on a faraway planet, but it also provides a path to identify life itself," de Wit said.

JWST found the unambiguous signature of water on exoplanet WASP-96B. A new technique may make it even easier for telescopes like JWST to find water.

Although the approach looks like it’ll work in principle, there may still be hurdles, as it’s not clear how many terrestrial exoplanets also have atmospheres. "Finding the perfect system to test this on might turn out to be a little bit more challenging than we previously thought," Casewell told Live Science.

But as researchers keep discovering more exoplanets, more atmospheres will also be spotted. And this technique could help figure out whether they could sustain life.