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Scientists have solved the mystery of the Seychelles’ vanished crocodiles using DNA from historic museum specimens。 The reptiles were not a unique species after all, but an isolated population of saltwater crocodiles that likely drifted thousands of kilometers across the Indian Ocean
Supernovae characterized by enduring narrow optical hydrogen emission lines (SNe IIn) are believed to result primarily from the core-collapse of massive stars undergoing sustained interaction with a dense circumstellar medium (CSM). While the properties of SN IIn progenitors have relatively few direct constraints, the ongoing ejecta-CSM interaction provides unique information about late-stage stellar mass-loss preceding core-collapse. We present late-time X-ray and radio observations of four $\geq$3000 day-old SNe IIn: SN 2013L, SN 2014ab, SN 2015da, and KISS15s. The radio and X-ray emission from KISS15s indicate a mass-loss rate of \eq{\dot M\sim4\times 10^{-3}~\rm{M_{\odot}\,yr^{-1}}} at $\sim$450 years pre-supernova -- 2 orders of magnitude below earlier optical estimates (which probed the mass loss immediately preceding the supernova). We find hints of a spectral inversion in the radio SED of KISS15s; a possible signature of a secondary shock due to a binary system or the emergence of a pulsar wind. For SN 2013L, we obtain a mass-loss rate of \eq{\dot M\sim2 \times 10^{-3}~\rm{M_{\odot}\,yr^{-1}}} at $\sim$400 years pre-explosion based on the X-ray detection. For SN 2014ab and
Two groups recently analyzed the long-term orbital evolution of HM Cancri, which is one of the most important verification binaries for the space gravitational wave detector LISA. By using the reported first and second derivatives of its orbital frequency $f$, we discuss potential tertiary effects on this binary. We found that, in contrast to the first derivative $\dot f$, the second derivative $\ddot f$ might be strongly affected by a dark tertiary component such as an old white dwarf with an outer orbital period of $\sim$250 years.
Gravity is, by far, one of the scientific themes that have most piqued the curiosity of scientists and philosophers over the centuries. The history of science tells us that when the creative effort of physicists and philosophers to solve the main puzzles of the understanding of our universe met, a new conceptual revolution has started. However, since Einstein's relativistic theories and the subsequent advent of quantum mechanics, physicists and philosophers have taken different paths, both kidnapped by the intrinsic conceptual and mathematical difficulties inherited by their studies. Is it possible to restore a unitary vision of knowledge, overcoming the scientific-humanistic dichotomy that has established itself over time? The answer is certainly not trivial, but we can start from school to experience a new vision of a unified knowledge. From this need, the Gravitas project has born. Gravitas is a multidisciplinary outreach and educational program devoted to high school students (17-19 years old) that mixes contemporary physics and the philosophy of science. Coordinated by the Cagliari Section of the National Institute of Nuclear Physics, in Italy, Gravitas has started on December
"We look forward to working with Roscosmos on a collaborative approach to address the leaks
The reactor, from a startup called Antares, isn't ready to generate power yet
A team at the University of Minnesota discovered that changing a metal film's thickness by just a few nanometers can dramatically alter how it behaves electronically。 The finding reveals a surprising new way to control metals and could help power future advances in electronics, catalysis, and quantum technology
Scientists have successfully tested an AI-designed universal coronavirus vaccine in humans for the first time, finding it to be safe and well tolerated。 The vaccine generated immune responses against multiple coronaviruses, including SARS-CoV-2, SARS, and related bat viruses with pandemic potential。 By targeting features shared across an entire vir
As traditional chip miniaturization slows, researchers have found a way to pack more computing power into the same space by stacking silicon circuits in multiple layers。 The new process uses ultra-thin silicon membranes and low-temperature manufacturing techniques to overcome a major obstacle that has long blocked the production of true 3D chips
Astronomers have finally cracked the mystery behind a strange class of repeating cosmic signals that has baffled scientists for years。 Using Australia’s ASKAP radio telescope, researchers traced the bursts to a rare stellar duo in which a dense white dwarf is relentlessly siphoning material from a nearby red dwarf companion。 As the stolen matter sp
Researchers have developed a compact quantum detector that makes terahertz radiation much easier to detect。 A specially designed metasurface funnels incoming energy into tiny active regions, greatly strengthening the electrical signal produced。 The approach boosted efficiency by roughly 20 times compared to earlier designs and could pave the way fo
In the end, the three companies involved all point the finger at each other
Scientists used some of the most advanced plasma simulations ever created to uncover how the universe builds enormous magnetic fields out of turbulence。 The discovery could reshape our understanding of stars, black holes, neutron star collisions, and dangerous solar eruptions
Money would keep coal plants open, build the first new plants in over a decade
June's night sky delivers several must-see events, starting with a close encounter between Venus and Jupiter after sunset。 Mercury joins the pair to form a rare three-planet lineup, while the Moon puts on a special show by passing in front of Venus for viewers in parts of the Americas。 The month also marks the start of astronomical summer and the r
NASA’s Psyche spacecraft just used Mars as a giant gravitational slingshot to continue its journey toward a strange metal rich asteroid。 The close flyby boosted the spacecraft’s speed by about 1,000 mph while also producing rare crescent images of Mars glowing through its dusty atmosphere
Scientists have developed a solar desalination system that turns seawater into drinking water without creating environmentally damaging brine。 Special laser-textured metal panels use sunlight to evaporate water while automatically moving salt deposits away from the working surface, preventing clogging。 The process was successfully tested with water
A giant planet nearly 700 light-years away has a bizarre daily weather cycle where mineral clouds appear every morning and vanish by nightfall。 Using the James Webb Space Telescope, astronomers discovered that WASP-94A b’s mornings are filled with clouds made of rock-like minerals, while its evenings are surprisingly clear。 The finding gave scienti
Head's true genius—and that of his character, Giles—lay in quietly filling in the gaps in every scene
Scientists say moons around rogue planets wandering through the galaxy could remain warm enough for life thanks to tidal heating and hydrogen-rich atmospheres。 These dark, starless worlds may have had stable oceans for billions of years — long enough for complex life to potentially emerge