Posts

The researchers conclude that, over Earth’s history, a larger amount of Earth’s mantle has melted – and ultimately formed the Earth’s crust – than previously thought. “To sustain the material budget between Earth’s mantle and crust, mass fluxes between the surface and Earth’s interior must have operated at a higher rate,” says Münster University’s Prof. Andreas Stracke, who is heading the study. As the material below the Azores rises from very deep within Earth’s mantle – and is unexpectedly similar to most of its upper part – the composition of Earth’s entire mantle may differ from current thinking....

The material that forms W40’s wings was ejected from a dense cluster of stars that lies between the wings in the image. The hottest, most massive of these stars, W40 IRS 1a, lies near the center of the star cluster. W40 is about 1,400 light-years from the Sun, about the same distance as the well-known Orion nebula, although the two are almost 180 degrees apart in the sky. Launched on August 25, 2003, NASA’s Spitzer Space Telescope’s goal was to provide a unique, infrared view of the universe and allow us to peer into regions of space that are hidden from optical telescopes....

The universe is so big, and it takes so long for most celestial objects to change, that it is rare a telescope can catch something in motion. It helps if the target is moving at nearly the speed of light, and that the Hubble Space Telescope’s crystal-clear view can catch subtle changes in one-tenth the time it might take for a ground-based telescope. Astronomers collected 500 Hubble pictures, taken over 13 years to make a movie flipbook of a blowtorch-like jet of gas blasted from the vicinity of a supermassive black hole....

The US Defense Advanced Research Projects Agency (Darpa) has recently commissioned three private companies, Blue Origin, Lockheed Martin and General Atomics, to develop nuclear fission thermal rockets for use in lunar orbit. Such a development, if flown, could usher in a new era of spaceflight. That said, it is only one of several exciting avenues in rocket propulsion. Here are some others. Chemical rockets The standard means of propulsion for spacecraft uses chemical rockets....

Two-Minute Tour: An Ultra-Compact Dwarf Galaxy Astronomers may have discovered the densest galaxy in the nearby Universe. The galaxy, known as M60-UCD1, is located about 54 million light years from Earth. M60-UCD1 is packed with an extraordinary number of stars and this has led scientists to classify it as an “ultra-compact dwarf galaxy.” This means that this galaxy is smaller and has more stars than just a regular dwarf galaxy....

Pneumocell in Austria, an inflatable structures specialist, performed a system study of an inflatable lunar habitat, based on prefabricated ultralight structures. Once inflated, these habitats would be buried under 4-5 m (13-16 feet) of lunar regolith for protection from radiation and micrometeorites. A truss holding a mirror membrane would be erected above each habitat. It would be designed to rotate to follow the Sun throughout the sky. Sunlight from the mirror would be directed down through an artificial crater, from which another cone-shaped mirror reflects it into the surrounding greenhouse....

How is it possible to move in the desired direction without a brain or nervous system? Single-celled organisms apparently manage this feat without any problems: for example, they can swim towards food with the help of small flagellar tails. How these extremely simply built creatures manage to do this was not entirely clear until now. However, a research team at TU Wien (Vienna) has now been able to simulate this process on the computer: They calculated the physical interaction between a very simple model organism and its environment....

Researchers at EPFL’s Distributed Information Systems Laboratory (LSIR) have come up with a way to make the news industry more transparent. Their initiative, Media Observatory, maps out the Swiss and international media landscape through the topics that local media outlets choose to cover. It then uses those choices to identify possible outside influences on the outlets. “The main difficulty in this approach is the absence of an objective baseline: the simple act of selecting stories is inherently biased....

New findings reveal how ants increase their collective sensing power to help them navigate complex terrains. Ants use their numbers to overcome navigational challenges that are too large and disorienting to be tackled by any single individual, reports a new study in the open-access journal eLife. The results demonstrate the potential advantages of group living and collective cognition in making certain environments habitable for a species. “Cooperation is a common means by which animals can increase their cognitive capacity, and we were intrigued as to whether this cooperation allows ants to extend the range of environments in which they can efficiently collect food,” says first author Aviram Gelblum, a postdoctoral fellow in senior author Ofer Feinerman’s lab at the Weizmann Institute of Science, Israel....

The internet is an indispensable communication tool, connecting tens of billions of devices worldwide, and yet we struggle to connect to the web from under water. “People from both academia and industry want to monitor and explore underwater environments in detail,” explains the first author, Basem Shihada. Wireless internet under the sea would enable divers to talk without hand signals and send live data to the surface. Underwater communication is possible with radio, acoustic and visible light signals....

Using the International Gemini Observatory, astronomers have discovered the closest-known black hole to Earth. This is the first unambiguous detection of a dormant stellar-mass black hole in the Milky Way. Located a mere 1600 light-years away, its close proximity to Earth offers an intriguing target of study to advance our understanding of the evolution of binary systems. Black holes are the most extreme objects in the Universe. It is believed that supermassive versions of these unimaginably dense objects reside at the centers of all large galaxies....

NASA’s New Horizons mission revolutionized our knowledge of Pluto when it flew past that distant world in July 2015. Among its many discoveries were images of strange formations resembling giant knife blades of ice, whose origin had remained a mystery. Now, scientists have turned up a fascinating explanation for this “bladed terrain”: the structures are made almost entirely of methane ice, and likely formed as a specific kind of erosion wore away their surfaces, leaving dramatic crests and sharp divides....

The switch included bringing online the backup Power Control Unit (PCU) and the backup Command Unit/Science Data Formatter (CU/SDF) on the other side of the Science Instrument and Command & Data Handling (SI C&DH) unit. The PCU distributes power to the SI C&DH components, and the CU/SDF sends and formats commands and data. In addition, other pieces of hardware onboard Hubble were switched to their alternate interfaces to connect to this backup side of the SI C&DH....

“Bats are an exciting group to study because they have evolved so many different hunting strategies,” Page said. “In this review, we look broadly across bats worldwide to investigate the patterns and processes underlying the sensory and cognitive adaptations bats have evolved to successfully hunt their prey.” Bats hunting in open spaces, high above the forest or over water, depend primarily on their echolocation systems. When they receive an echo from a prey, they produce more and more frequent signals—producing what is called a feeding buzz—as they go in for the kill....

Gut bacteria brew all sorts of chemicals, but we don’t know what most of them do. A new study suggests that one such compound, previously linked to cancer, may serve as a bizarre weapon in microbial skirmishes. Some gut bacteria have a spooky superpower: they can reanimate dormant viruses lurking within other microbes. This viral awakening unleashes full-blown infections that destroy the virus-carrying cells, Howard Hughes Medical Institute Investigator Emily Balskus’s lab first published as a preprint on bioRxiv....

The Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) mission team is continuing to work towards recovery of the spacecraft orientation control. This work includes collecting information from the spacecraft, running simulations, and refining recovery plans. CAPSTONE is currently power positive. This means that it is generating more power from its solar panels than the spacecraft systems are using. The spacecraft remains in a stable condition on track to the Moon....

NASA’s Cassini spacecraft spied details on the pockmarked surface of Saturn’s moon Prometheus (86 kilometers, or 53 miles across) during a moderately close flyby on December 6, 2015. This is one of Cassini’s highest resolution views of Prometheus, along with PIA18186 and PIA12593. This view looks towards the anti-Saturn side of Prometheus. North on Prometheus is up. The image was taken in visible light with the Cassini spacecraft narrow-angle camera....

Galaxy clusters are the largest structures in the cosmos that are held together by gravity. Clusters consist of hundreds or even thousands of galaxies embedded in hot gas, and contain an even larger amount of invisible dark matter. Sometimes two galaxy clusters collide, as in the case of the Bullet Cluster, and occasionally more than two will collide at the same time. The new observations show a mega-structure being assembled in a system called Abell 1758, located about 3 billion light-years from Earth....

As artificial intelligence has attracted broad interest, researchers are focused on understanding how the brain accomplishes cognition so they can construct artificial systems with general intelligence comparable to humans’ intelligence. Many have approached this challenge by using conventional silicon microelectronics in conjunction with light. However, the fabrication of silicon chips with electronic and photonic circuit elements is difficult for many physical and practical reasons related to the materials used for the components....

One clue emerged when past studies discovered that a certain genetic change (mutation) is present in most people with the condition. This genetic mutation makes gut lining cells more vulnerable to damage. However, the mystery deepened again when it was learned that half of all Americans have this same risk-conferring genetic mutation, but fewer than half a million develop Crohn’s disease. Published on October 5, 2022, in the journal Nature, the new research in mice and in human tissue revealed for the first time that in healthy individuals, immune defenders called T cells secrete a protein called apoptosis inhibitor 5 (API5), which signals the immune system to stop the attack on gut lining cells....