Showing 20 articles starting at article 481

< Previous 20 articles        Next 20 articles >

Categories: Geoscience: Landslides, Space: Astrophysics

Return to the site home page

     (via sciencedaily.com) 

Astronomers have directly measured the mass of a single, isolated white dwarf -- the surviving core of a burned-out, Sun-like star. Researchers found that the white dwarf is 56 percent the mass of our Sun. This agrees with earlier theoretical predictions of the white dwarf's mass and corroborates current theories of how white dwarfs evolve as the end product of a typical star's evolution. The unique observation yields insights into theories of the structure and composition of white dwarfs.

     (via sciencedaily.com) 

Astronomers using data from the SMARTS 1.5-meter Telescope at the Cerro Tololo Inter-American Observatory (CTIO), have made the first confirmed detection of a star system that will one day form a kilonova -- the ultra-powerful, gold-producing explosion created by merging neutron stars. These systems are so phenomenally rare that only about 10 such systems are thought to exist in the entire Milky Way.

     (via sciencedaily.com) 

What happened shortly after the universe was born in the Big Bang and began to expand? Bubbles occurred and a previously unknown phase transition happened, according to particle physicists.

     (via sciencedaily.com) 

A group of scientists have released one of the most precise measurements ever made of how matter is distributed across the universe today.

     (via sciencedaily.com) 

A giant diffuse tail of stars has been discovered emanating from a large, faint dwarf galaxy. The presence of a tail indicates that the galaxy has experienced recent interaction with another galaxy. This is an important clue for understanding how so called 'ultra-diffuse' galaxies are formed.

     (via sciencedaily.com) 

Earth's potassium arrived by meteoritic delivery service finds new research led by Earth and planetary scientists. Their work shows that some primitive meteorites contain a different mix of potassium isotopes than those found in other, more-chemically processed meteorites. These results can help elucidate the processes that shaped our Solar System and determined the composition of its planets.

     (via sciencedaily.com) 

Scientists have discovered the first gamma-ray eclipses from a special type of binary star system using data from NASA's Fermi Gamma-ray Space Telescope. These so-called spider systems each contain a pulsar -- the superdense, rapidly rotating remains of a star that exploded in a supernova -- that slowly erodes its companion.

     (via sciencedaily.com) 

The most sensitive telescope now searching for radio signals from cosmic dawn, an era around 200 million years after the Big Bang when stars ignited, has doubled its sensitivity, a new paper reports. While not yet detecting this radiation -- the redshifted 21-centimeter line -- they have put new limits on the elemental composition of galaxies during the Epoch of Reionization. Early galaxies seem to be low in metals, fitting the most popular theory of cosmic evolution.

     (via sciencedaily.com) 

Space weather can interfere with spaceflight and the operation of satellites, but the phenomenon is very difficult to study on Earth because of the difference in gravity. Researchers effectively reproduced the type of gravity that exists on or near stars and other planets inside of a glass sphere measuring 3 centimeters in diameter, or about 1.2 inches. The achievement could help scientists overcome the limiting role of gravity in experiments that are intended to model conditions in stars and other planets.

     (via sciencedaily.com)     Original source 

Astronomers used observations from the James Webb Space Telescope (JWST) to achieve the darkest ever view of a dense interstellar cloud. These observations have revealed the composition of a virtual treasure chest of ices from the early universe, providing new insights into the chemical processes of one of the coldest, darkest places in the universe as well as the origins of the molecules that make up planetary atmospheres.

     (via sciencedaily.com)     Original source 

A startling analysis from Globe at Night -- a citizen science program -- concludes that stars are disappearing from human sight at an astonishing rate. The study finds that, to human eyes, artificial lighting has dulled the night sky more rapidly than indicated by satellite measurements.

     (via sciencedaily.com) 

Research has revealed how supermassive black holes (SMBHs) are feeding off gas clouds which reach them by traveling hundreds of thousands of light years from one galaxy to another.

     (via sciencedaily.com) 

Las Vegas, with its rapid urbanization and desert landscape, is highly vulnerable to flooding. For this reason, flood managers have built an extensive system of drainage ditches and detention basins to protect the public. Now, a new study shows how intentional engineering and urban development are interacting with climate change to alter the timing and intensity of flood risk.

     (via sciencedaily.com)     Original source 

Astronomers have released a gargantuan survey of the galactic plane of the Milky Way. The new dataset contains a staggering 3.32 billion celestial objects -- arguably the largest such catalog so far. The data for this unprecedented survey were taken with the Dark Energy Camera.

     (via sciencedaily.com)     Original source 

Our solar system is estimated to be about 4.57 billion years old. Previous analyses of ancient meteorites have shown that minerals were created through chemical reactions with water as far back as 4.5 billion years ago. New findings from the Ryugu asteroid samples indicate that carbonates were forming from water-rock reactions several million years earlier, even closer to the solar system's beginnings.

     (via sciencedaily.com) 

A new modelling study shows that the Seychelles and other islands in the western Indian Ocean are not responsible for most of the plastic waste that accumulates on their beaches. Indonesia, India, and Sri Lanka were found to be the main sources of land-based plastic debris. The Seychelles also accumulate significant amounts of plastic debris of marine origin from fisheries and shipping lanes. • The results highlight the urgent need for a legally-binding Global Plastics Treaty and greater enforcement of regional policies to reduce plastic waste.

     (via sciencedaily.com) 

Recent research shows that magnetic fields can spontaneously emerge in a plasma if the plasma has a temperature anisotropy. This mechanism is known as the Weibel instability. This new research is the first to unambiguously observe the Weibel instability in the laboratory. It offers a possible solution to the problem of the origin of the microgauss-level magnetic fields that permeate the galaxies.

     (via sciencedaily.com) 

Hundreds of millions of light-years away in a distant galaxy, a star orbiting a supermassive black hole is being violently ripped apart under the black hole's immense gravitational pull. As the star is shredded, its remnants are transformed into a stream of debris that rains back down onto the black hole to form a very hot, very bright disk of material swirling around the black hole, called an accretion disc. This phenomenon -- where a star is destroyed by a supermassive black hole and fuels a luminous accretion flare -- is known as a tidal disruption event (TDE), and it is predicted that TDEs occur roughly once every 10,000 to 100,000 years in a given galaxy.

     (via sciencedaily.com) 

Understanding how dust grains form in interstellar gas could offer significant insights to astronomers and help materials scientists develop useful nanoparticles.

     (via sciencedaily.com) 

A team has studied the relation between galaxy size and luminosity of some of the earliest galaxies in the universe taken by the James Webb Space Telescope, less than a billion years after the Big Bang.