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Combination of a Hubble Space Telescope image of SN 1987A and the compact argon source. The faint blue source in the centre is the emission from the compact source detected with the JWST/NIRSpec instrument. Outside this is the stellar debris, containing most of the mass, expanding at thousands of km/second. The inner bright "string of pearls" is the gas from the outer layers of the star that was expelled about 20,000 years before the final explosion. The is the fast debris are now colliding with the ring, explaining the bright spots. Outside of the inner ring are two outer rings,...

1.) How did the Universe begin? What “type” of inflation occurred? What preceded and/or caused inflation? 2.) What explains neutrino mass? Are neutrinos Dirac or Majorana particles? Are there heavy, sterile neutrino species? 3.) Why is our Universe matter-dominated? More matter than antimatter permeates the Universe. 4.) What is dark matter? Its effects are understood, not its underlying cause. 5.) What is dark energy? Its properties indicate a constant, positive spatial energy density.

A fiery-looking, red-orange energetic jet blasting bright light from the center of a galaxy. An artist's illustration of neutrinos originating from a high-energy Blazar Benjamin Amend, Clemson University Born in the cradle of deep space, blasting across the universe at nearly the speed of light and harnessing energy up to a million times greater than anything achieved by the world's most powerful particle accelerator, cosmic rays are atom fragments that relentlessly rain down on Earth. They get caught in our atmosphere and mess up our satellites. They threaten the health of astronauts living in orbit, even when sparse in number....

Observations of galactic rotation curves give one of the strongest lines of evidence pointing towards the existence of dark matter, a non-baryonic form of matter that makes up an estimated 85% of the matter in the observable Universe. Current assessments of galactic rotation curves are based upon a framework of Newtonian accounts of gravity, a new article suggests that if this is substituted with a general relativity-based model, the need to recourse to dark matter is relieved, replaced by the effects of gravitomagnetism.

Explanation: From where do these neutrinos come? The IceCube Neutrino Observatory near the South Pole of the Earth has begun to detect nearly invisible particles of very high energy. Although these rarely-interacting neutrinos pass through much of the Earth just before being detected, where they started remains a mystery. Pictured here is IceCube's Antarctic lab accompanied by a cartoon depicting long strands of detectors frozen into the crystal clear ice below. Candidate origins for these cosmic neutrinos include the violent surroundings of supermassive black holes at the centers of distant galaxies, and tremendous stellar explosions culminating in gamma ray bursts...

Pip-squeak particles called neutrinos are dishing out more than scientists had bargained for.A particle detector has spotted a puzzling abundance of the lightweight subatomic particles and their antimatter partners, antineutrinos, physicists report May 30 at arXiv.org. The finding mirrors a neutrino excess found more than two decades ago. And that match has researchers wondering if a new type of particle called a sterile neutrino — one even more shadowy than the famously elusive ordinary neutrinos — might be at large.Such a particle, if it exists, would transform the foundations of particle physics and could help solve cosmic puzzles like the...

IT TRIGGERED A SUBATOMIC CASCADE — AND COULD HAVE AN AVALANCHE OF IMPLICATIONS FOR THE FUTURE OF PHYSICS.Crash Course Scientists have now confirmed that an unusually powerful particle of antimatter crashed down into Antarctica back in December 2016. The collision seems to have triggered a subatomic cascade effect called Glashow resonance, Live Science reports, which is a theoretical phenomenon that requires more energy to set off than even the most powerful particle accelerators can provide. Scientists didn’t expect to see tangible evidence of Glashow resonance, but now that they have it helps further confirm the Standard Model of subatomic physics....

On December 6, 2016, a high-energy particle called an electron antineutrino hurtled to Earth from outer space at close to the speed of light carrying 6.3 petaelectronvolts (PeV) of energy. Deep inside the ice sheet at the South Pole, it smashed into an electron and produced a particle that quickly decayed into a shower of secondary particles. The interaction was captured by a massive telescope buried in the Antarctic glacier, the IceCube Neutrino Observatory. IceCube had seen a Glashow resonance event, a phenomenon predicted by Nobel laureate physicist Sheldon Glashow in 1960. With this detection, scientists provided another confirmation of...

Exotic subatomic particles, sterile neutrinos, are no-shows in experiments, increasing doubts about their existence. University of Cincinnati physicists, as part of an international research team, are raising doubts about the existence of an exotic subatomic particle that failed to show up in twin experiments. UC College of Arts and Sciences associate professor Alexandre Sousa and assistant professor Adam Aurisano took part in an experiment at the Fermi National Accelerator Laboratory in search of sterile neutrinos, a suspected fourth "flavor" of neutrino that would join the ranks of muon, tau, and electron neutrinos as elementary particles that make up the known...

In tunnels deep inside a granite mountain at Daya Bay, a nuclear reactor facility some 55 kilometers from Hong Kong, sensitive detectors are hinting at the existence of a new form of neutrino, one of nature's most ghostly and abundant elementary particles. Neutrinos, electrically neutral particles that sense only gravity and the weak nuclear force, interact so feebly with matter that 100 trillion zip unimpeded through your body every second. They come in three known types: electron, muon and tau. The Daya Bay results suggest the possibility that a fourth, even more ghostly type of neutrino exists - one more...

The KATRIN discovery stems from direct, high-precision measurements of how a rare type of electron-neutrino pair share energy. This approach is the same as neutrino mass experiments from the 1990s and early 2000s...both of which set the previous upper limit of the mass at 2 eV. The heart of the KATRIN experiment is the source that generates electron-neutrino pairs: gaseous tritium, a highly radioactive isotope of hydrogen. As the tritium nucleus undergoes radioactive decay, it emits a pair of particles: one electron and one neutrino, both sharing 18,560 eV of energy. KATRIN scientists cannot directly measure the neutrinos, but they...

A Neutrino Beam Beaconby Paul Gilsteron May 17, 2019 If you want to look for possible artifacts of advanced civilizations, as do those practicing what is now being called Dysonian SETI, then it pays to listen to the father of the field. My friend Al Jackson has done so and offers a Dyson quote to lead off his new paper: “So the first rule of my game is: think of the biggest possible artificial activities with limits set only by the laws of physics and look for those.” Dyson wrote that in a 1966 paper that repays study today (citation...

Researchers at the XENON dark matter observatory have spotted something incredibly rare. Unfortunately, it’s not dark matter, but it is the next best thing. The detectors at the observatory have spotted the decay of xenon-124, the rarest event ever recorded in human history. The XENON experiment is designed to detect dark matter, which is not an easy task. The reason that dark matter is so mysterious is that it pretty much never does anything, which makes it hard to spot. Dark matter doesn’t give off light, or have any sort of magnetic field, and it almost never interacts with normal...

It takes 1 trillion times the age of the universe for a xenon-124 sample to shrink by half For the first time, researchers have directly observed an exotic type of radioactive decay called two-neutrino double electron capture.The decay, seen in xenon-124 atoms, happens so sparingly that it would take 18 sextillion years (18 followed by 21 zeros) for a sample of xenon-124 to shrink by half, making the decay extremely difficult to detect. The long-anticipated observation of two-neutrino double electron capture, reported in the April 25 Nature, lays the groundwork for researchers to glimpse a yet unseen, even rarer version...

Scientists revel in exploring mysteries, and the bigger the mystery, the greater the enthusiasm. There are many huge unanswered questions in science, but when you're going big, it's hard to beat "Why is there something, instead of nothing?" That might seem like a philosophical question, but it's one that is very amenable to scientific inquiry. Stated a little more concretely, "Why is the universe made of the kinds of matter that makes human life possible so that we can even ask this question?" Scientists conducting research in Japan have announced a measurement last month that directly addresses that most fascinating...

Scientists have produced the firmest evidence yet of so-called sterile neutrinos, mysterious particles that pass through matter without interacting with it at all. The first hints these elusive particles turned up decades ago. But after years of dedicated searches, scientists have been unable to find any other evidence for them, with many experiments contradicting those old results. These new results now leave scientists with two robust experiments that seem to demonstrate the existence of sterile neutrinos, even as other experiments continue to suggest sterile neutrinos don't exist at all. That means there's something strange happening in the universe that is...

"We Truly Don't Know What It Is" --Mystery Milky-Way Spectrum of Light Observed 'Not Produced By Any Known Emission' April 17, 2018   "We use special telescopes to catch X-ray light in the sky, and while looking at these X-rays, the telescopes noticed an unexpected feature and captured a spectrum of light, which is not produced by any known atomic emission," said University of Miami astrophysicist Nico Cappelluti. "This emission line is now called the 3.5 kiloelectron volt (keV). One interpretation of this emission line is that it's produced by the decay of dark matter." "This 3.5 keV emission line is...

POSSIBLY the clearest skies on Earth have been found - but to exploit them, astronomers will have to set up a telescope in one of the planet's harshest climates...[Scientists] evaluated different factors that affect telescope vision, such as the amount of water vapour, wind speeds and atmospheric turbulence...The team found that the Antarctic plateau offers world-beating atmospheric conditions - as long as telescopes are raised 20 meters above its frozen surface...[The Antarctic air is] drier than the Atacama desert in Chile [where some of the best telescopes in the world are currently located].

Cosmologists Probe Mystery Of Dark Energy With South Pole Telescope ScienceDaily (Apr. 3, 2008) — Something is pulling the universe apart. What is it, and where will it take us from here? Scientists at the Kavli Institute for Cosmological Physics, University of Chicago, seek answers to those questions with the newly-commissioned South Pole Telescope. Frigid and bone-dry, with six straight months of night each year, the South Pole is a forbidding place to live or work. But for largely the same reasons, it’s one of the best spots on the planet for surveying the faint cosmic microwave background (CMB) radiation...

Ron Cowen 3-22-2016 In tunnels deep inside a granite mountain at Daya Bay, a nuclear reactor facility some 55 kilometers from Hong Kong, sensitive detectors are hinting at the existence of a new form of neutrino, one of nature’s most ghostly and abundant elementary particles.Neutrinos, electrically neutral particles that sense only gravity and the weak nuclear force, interact so feebly with matter that 100 trillion zip unimpeded through your body every second. They come in three known types: electron, muon and tau. The Daya Bay results suggest the possibility that a fourth, even more ghostly type of neutrino exists —...