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“The Stardust samples, microscopic grains from a body less than two miles wide, contain a record of the deep past covering billions of miles,” said Dr. Ryan Ogliore. “After 18 years of interrogating this comet, we have a much better view of the solar system’s dynamic formative years.”


What can samples collected from a comet almost 20 years ago tell us about the history of comets and our solar system? This is what a recent study published in Geochemistry hopes to address as a researcher from the Washington University in St. Louis (WUSTL) analyzed samples from Comet 81P/Wild 2 that were returned to Earth almost exactly 18 years ago today. This study holds the potential to help scientists not only gain greater insights into the origin and history of comets, but of our solar system, as well.

Image of the Stardust sample return capsule being retrieved inside a protective covering after it was collected from its landing site at the U.S. Air Force Utah Test and Training Range in January 2006. (Credit: NASA)

While Comet 81P/Wild 2 currently orbits in the main asteroid belt between Mars and Jupiter, scientists have long hypothesized that the comet formed much farther out, possibly beyond the orbit of Neptune. Therefore, they interpreted that any samples collected from the comet would contain material from the interstellar medium before the formation of the solar system. However, the samples that returned to Earth from NASA’s Stardust mission have revealed material comprised of a variety of events that occurred during the early age of the solar system, as opposed to strictly before the solar system formed.

Just like a book can’t be judged by its cover, a material can’t always be judged by its surface. But, for an elusive conjectured class of materials, physicists have now shown that the surface previously thought to be “featureless” holds an unmistakable signature that could lead to the first definitive observation.

Higher-order , or HOTIs, have attracted attention for their ability to conduct electricity along one-dimensional lines on their surfaces, but this property is quite difficult to experimentally distinguish from other effects. By instead studying the interiors of these materials from a , a team of physicists has identified a signature that is unique to HOTIs that can determine how light reflects from their surfaces.

As the team reports in the journal Nature Communications, this property could be used to experimentally confirm the existence of such topological states in real materials.

Just like humans, plants also communicate with each other as soon as any danger or attack is detected in their neighbourhood. Scientists know about this phenomenon since the 1980s, having identified at least 80 species who act in their defence in crisis situations. However, it was still shrouded in mystery as to how exactly plants receive such danger signals from their neighbours.

Now, a team of Japanese scientists has not just solved this puzzle but also filmed the communication among plants in an amazing video. In a study published in Nature Communications, molecular biologists at Saitama University in Japan, Yuri Aratani and Takuya Uemura, demonstrated how these plants behave upon detecting danger.

To conduct the experiment, scientists set off caterpillars on leaves cut from tomato plants and a commonly used weed called Arabidopsis thaliana. To better analyse its impact on the neighbouring plant, the compounds were concentrated in a plastic bottle and pumped onto the recipient plant at a constant rate.

Rishi Sunak needs to decide whether he wants to back the UK’s creative industries or gamble everything on an artificial intelligence boom, the chief executive of Getty Images has said.

Craig Peters, who has led the image library since 2019, spoke out amid growing anger from the creative and media sector at the harvesting of their material for “training data” for AI companies. His company is suing a number of AI image generators in the UK and US for copyright infringement.

Summary: Researchers create a transparent graphene-based neural implant offering high-resolution brain activity data from the surface. The implant’s dense array of tiny graphene electrodes enables simultaneous recording of electrical and calcium activity in deep brain layers.

This innovation overcomes previous implant limitations and offers insights for neuroscientific studies. The transparent design allows optical imaging alongside electrical recording, revolutionizing neuroscience research.