A quirky material that behaves like a mishmash of liquid and solid could be hidden deep in the Earth.

Computer simulations described in two studies suggest that the material in Earth's inner core, which includes iron and other, lighter elements, may be in a "superionic" state. That means that while the iron stays put, as in a solid, the lighter elements flow like a liquid.

The research gives a potential peek at the inner workings of an enigmatic, inaccessible realm of the planet. According to conventional scientific wisdom, Earth's core consists of a liquid outer core surrounding a solid inner core (SN: 1/28/19). But beyond knowing that the inner core is rich in iron, scientists don't know exactly which other elements are present, and in what quantities.

A research team led by Lund University in Sweden has provided an important clue to the origin of the element Ytterbium in the Milky Way, by showing that the element largely originates from supernova explosions. The groundbreaking research also provides new opportunities for studying the evolution of our galaxy. The study is published in Astronomy & Astrophysics.

Ytterbium is one of four elements in the periodic table named after the Ytterby mine in the Stockholm archipelago. The element was first discovered in the black mineral gadolinite, which was first identified in the Ytterby mine in 1787.

Ytterbium is interesting because it may have two different cosmic origins. Researchers believe that one half comes from heavy stars with short lives, while the other half comes from more regular stars, much like the sun, and that they create Ytterbium in the final stages of their relatively long lives.

"By studying stars formed at different times in the Milky Way, we have been able to investigate how fast the Ytterbium content increased in the galaxy. What we have succeeded in doing is adding relatively young stars to the study", says Martin Montelius, astronomy researcher at Lund University at the time of the research, and now at the University of Groningen.

The asteroid that killed nearly all dinosaurs struck Earth during springtime. An international team of scientists from the Vrije Universiteit (VU) Amsterdam (The Netherlands), Uppsala University (Sweden), Vrije Universiteit Brussel (Belgium) and the ESRF, the European Synchrotron (France), have determined when the meteorite crashed into the Earth after analyzing the remains of fishes that died just after the impact. Their results are published in the journal Nature today.

Around 66 million years ago, the so-called Chicxulub meteorite crashed into the Earth in what today is the Yucatán peninsula in Mexico, marking the demise of dinosaurs and the end of the Cretaceous period. This mass extinction still puzzles scientists today, as it was one of the most selective in the history of life: all non-avian dinosaurs, pterosaurs, ammonites, and most marine reptiles disappeared, while mammals, birds, crocodiles, and turtles survived.

Meta founder Mark Zuckerberg has unveiled several ambitious artificial-intelligence projects, describing AI as "the key to unlocking the Metaverse".

In a livestreamed demonstration, he created a basic virtual world - including an island, trees and a beach - using the AI feature Builder Bot.

Mr Zuckerberg also announced a plan to build a universal speech translator.

When we attached tiny, backpack-like tracking devices to five Australian magpies for a pilot study, we didn't expect to discover an entirely new social behaviour rarely seen in birds.

Our goal was to learn more about the movement and social dynamics of these highly intelligent birds, and to test these new, durable and reusable devices. Instead, the birds outsmarted us.

As our new research paper explains, the magpies began showing evidence of cooperative "rescue" behaviour to help each other remove the tracker.

While we're familiar with magpies being intelligent and social creatures, this was the first instance we knew of that showed this type of seemingly altruistic behaviour: helping another member of the group without getting an immediate, tangible reward.

The strange weather was found in the 1st detailed study of the exoplanet's 'dark side.'

Imagine a world where the clouds are made of metal and liquid rubies and sapphires rain down from the sky. A new study shows that, on the hot Jupiter exoplanet WASP-121 b, this could be the reality.

In 2015, scientists discovered WASP-121 b, a gas giant exoplanet 880 light-years from Earth. The alien world is what is known as a "hot Jupiter," a class of gas giants that have physical similarities to Jupiter but orbit their stars much closer (hence, their "hot" nature). Since its discovery, researchers have further explored this world and its strange atmosphere.

In a new study, scientists using the Hubble Space Telescope have made the first detailed measurement of the atmosphere on the planet's cooler nightside. And this nighttime atmosphere seems to have a number of strange and remarkable qualities including metal clouds and rain made of what could be liquid gems.

Does the brain replay our best memories?

Our brains are pretty active and coordinated even as the body meets its demise. Researchers captured brainwaves during an individual's death and found semblance to high cognition activities such as dreaming or meditating, a recently published study has shown.

Even as humanity strives to learn more about the death of stars, there is a lot that we do not know about our deaths. Technology might help us live beyond our deaths somehow, but we do not know for sure what comes to pass as one dies. Now, a chance observation has given us our first glimpse of what happens in our brains as we die.

Continuous EEG and brain waves

An 87-year-old man was admitted to an emergency unit in Estonia after a fall. The patient was operated upon but faced as many as 12 epileptic attacks post-surgery. As part of monitoring the individual, doctors used continuous electroencephalography (EEG) that provided a means to detect the seizures. Unfortunately, the patient suffered a heart attack during this time and passed away. However, the continuous EEG monitor provided the first-ever recording of human brain activity during death.

Researchers also find salt deposits in an impact crater on the dwarf planet.
The third-largest crater on the dwarf planet Ceres was geologically active at least once many millions of years after its formation. In a recent study published today in the journal Nature Communications, researchers from the Max Planck Institute for Solar System Research (MPS) in Göttingen, the University of Münster (WWU) and the National Institute of Science Education and Research (NISER) in Bhubaneswar, India present the most detailed study of Urvara crater to date. For the first time, they evaluated camera images from the last phase of NASA's Dawn mission, which reveal geological structures only a few meters in size. The Dawn spacecraft entered orbit around the dwarf planet in 2015 and studied it up close for about three and a half years. Like Occator crater, Urvara crater may have been the scene of cryovolcanic activity, the researchers argue. The study supports the picture that a global saline ocean extended beneath Ceres' crust, some of which may still be liquid today.

Numerous large craters cover the surface of dwarf planet Ceres, the largest body in the asteroid belt at about 960 kilometers in diameter. Probably the most striking of these craters is Occator located in the northern hemisphere. The bright spots in its interior, which were already clearly visible during Dawn's approach phase, turned out to be saline remnants of a subsurface brine, which rose to the surface through cryovolcanic processes until recent geological times. In another large crater, called Ernutet, there is evidence of exposed organic compounds and thus very complex chemistry. In their latest publication, researchers led by the MPS now turn their attention to Urvara crater. Located in the southern hemisphere, it is Ceres' third largest crater, with a diameter of 170 kilometers. The impact that formed it about 250 million years ago is thought to have revealed material from depths of up to 50 kilometers.

"The large impact structures on Ceres give us access to the deeper layers of the dwarf planet," explains Andreas Nathues of the MPS, first author of the current study and Lead Investigator of Dawn's camera team. "As it turns out, the current topography and mineralogical composition of some of Ceres' large craters is the result of complex and long-lasting geological processes that have altered the dwarf planet's surface," he adds.

Of 18 fish, 17 responded to the visual cue of a mark on their body when presented with a mirror during a study

Mirror self-recognition (MSR) is seen as evidence for self-awareness and passing the mark test, in which animals touch or scrape a mark placed on their body in a location that can only be indirectly viewed in a mirror, is used to determine the capacity of an animal for MSR. Aside from chimpanzees, the evidence for other animals having passed the mark test has been criticized and thus inconclusive. By addressing criticisms placed against their previous work on the cleaner fish Labroides dimidiatus, an international team of researchers led by Masanori Kohda from the Graduate School of Science, Osaka City University, has provided further evidence to suggest the fish have the capacity for MSR.

This new experiment was recently published in PLOS Biology.

Professor Kohda says, "Previously, using a brown marking on the throat area of L. dimidiatus, we had shown three out of four cleaner fish to scrape their throats several times after swimming in front of a mirror, a number on par with similar studies done on other animals like elephants, dolphins, and magpies."

A complex hierarchical structure helps the lizard prevent accidental amputations

Lizards are famous for losing their tails, but perhaps the bigger question should be: How do their tails stay on? The answer may lie in the appendage's internal design. A structure of prongs, micropillars and nanopores holds a lizard's tail on tight enough to handle most jarring while remaining primed to drop the tail in case of emergency, researchers report in the Feb. 18 Science.

Self-amputation, or autotomy, of a limb is a common defense strategy in the animal kingdom, including for many lizard species (SN: 3/8/21). But it's a risky plan: A detachable limb brings with it increased risk of accidental loss from small bumps and snags. "It has to find the just right amount of attachment, so it doesn't come off easily. But it should also come off whenever it's needed," says Yong-Ak Song, a bioengineer at New York University Abu Dhabi in the United Arab Emirates. "It's a fine balance."