News (Page 760)

Researchers pinpoint origin of photons in mysterious gamma-ray bursts Scientists from the RIKEN Cluster for Pioneering Research and collaborators have used simulations to show that the photons emitted by long gamma-ray bursts, among the most energetic events to take place in the universe, originate in the photosphere—the visible portion of the “relativistic jet” that is emitted by exploding stars. phys.org Go to SourceRead More →

Ten years before the detection of gravitational waves, two KITP postdocs at UC Santa Barbara had a novel idea The history of science is filled with stories of enthusiastic researchers slowly winning over skeptical colleagues to their point of view. Astrophysicist Scott Hughes can relate to these tales. phys.org Go to SourceRead More →

VLA makes first direct image of key feature of powerful radio galaxies Astronomers used the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) to make the first direct image of a dusty, doughnut-shaped feature surrounding the supermassive black hole at the core of one of the most powerful radio galaxies in the Universe—a feature first postulated by theorists nearly four decades ago as an essential part of such objects. phys.org Go to SourceRead More →

Scientists prove that binary stars reflect light from one another UNSW astronomers have shown that binary stars – two stars locked in orbit around each other – reflect light as well as radiating it, revealing new ways for their detection. phys.org Go to SourceRead More →

Subaru telescope helps determine that dark matter is not made up of tiny primordial black holes An international team of researchers has put a theory speculated by the late Stephen Hawking to its most rigorous test to date, and their results based on the observations using the Subaru Telescope have ruled out the possibility that primordial black holes smaller than a tenth of a millimeter make up most of dark matter. phys.org Go to SourceRead More →

Astronomers take a closer look at a nearby dwarf active galactic nucleus An international team of astronomers has conducted optical and spectroscopic observations of the dwarf galaxy NGC 4395 that contains an active galactic nucleus (AGN). The observations, described in a paper published March 19 on arXiv.org, allowed the researchers to take a closer look at this dwarf AGN, what could provide essential insights into the nature of this object. phys.org Go to SourceRead More →

Star formation in galactic centers Stars form from the gas and dust in molecular clouds via a series of complex processes that are currently only partly understood, and the evolution of these clouds drives the evolution of the stellar populations in the universe. Astronomers studying the formation of stars have, over the past decades, concentrated on a few select regions of active star formation: the solar neighborhood, the disc of the Milky Way, and the neighboring Magellanic Cloud galaxies. This range of environments is limited, however, and not representative of the conditions under which most stars in the Universe formed. For instance, the densities, pressures,Read More →

Hubble spots flock of cosmic ducks This star-studded image shows us a portion of Messier 11, an open star cluster in the southern constellation of Scutum (the Shield). Messier 11 is also known as the Wild Duck Cluster, as its brightest stars form a “V” shape that somewhat resembles a flock of ducks in flight. phys.org Go to SourceRead More →

How to use gravitational waves to measure the expansion of the universe On the morning of Aug. 17, 2017, after traveling for more than a hundred million years, the aftershocks from a massive collision in a galaxy far, far away finally reached Earth. phys.org Go to SourceRead More →

Unusual galaxies defy dark matter theory After drawing both praise and skepticism, the team of astronomers who discovered NGC 1052-DF2 – the very first known galaxy to contain little to no dark matter – are back with stronger evidence about its bizarre nature. phys.org Go to SourceRead More →

LIGO and Virgo resume search for ripples in space and time The National Science Foundation’s LIGO (Laser Interferometer Gravitational-Wave Observatory) is set to resume its hunt for gravitational waves—ripples in space and time—on April 1, after receiving a series of upgrades to its lasers, mirrors, and other components. LIGO—which consists of twin detectors located in Washington and Louisiana—now has a combined increase in sensitivity of about 40 percent over its last run, which means that it can survey an even larger volume of space than before for powerful, wave-making events, such as the collisions of black holes. phys.org Go to SourceRead More →

Data flows from NASA’s TESS Mission, leads to discovery of Saturn-sized planet Astronomers who study stars are providing a valuable assist to the planet-hunting astronomers pursuing the primary objective of NASA’s new TESS Mission. phys.org Go to SourceRead More →