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Researchers predict location of novel candidate for mysterious dark energy Astronomers have known for two decades that the expansion of the universe is accelerating, but the physics of this expansion remains a mystery. Now, a team of researchers at the University of Hawai’i at Mānoa have made a novel prediction—the dark energy responsible for this accelerating growth comes from a vast sea of compact objects spread throughout the voids between galaxies. This conclusion is part of a new study published in The Astrophysical Journal. phys.org Go to SourceRead More →

Solar telescope GREGOR unveils magnetic details of the sun The Sun is our star and has a profound influence on our planet, life, and civilization. By studying the magnetism on the Sun, we can understand its influence on Earth and minimize damage of satellites and technological infrastructure. The GREGOR telescope allows scientists to resolve details as small as 50 km on the Sun, which is a tiny fraction of the solar diameter of 1.4 million km. This is as if one saw a needle on a soccer field perfectly sharp from a distance of one kilometer. phys.org Go to SourceRead More →

Astronomers identify 18 metal-poor stars in the Sagittarius dwarf galaxy Massachusetts Institute of Technology (MIT) astronomers have detected 18 very metal-poor stars in the Sagittarius dwarf galaxy. They found that one of the stars from the sample has an extremely low metallicity, slightly below -3.0. The study was reported in a paper published August 22 on the arXiv preprint repository. phys.org Go to SourceRead More →

Researchers design continuous-scanning sky brightness monitor in 2.5- to 5-μm band A research group led by Prof. Wang Jian from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) proposed a continuous-scanning near-infrared sky brightness monitor (CNISBM). It can measure 2.5 to 5 μm infrared sky brightness based on an InSb detector and a linear variable filter. phys.org Go to SourceRead More →

Does a black hole fire up cold heart of the Phoenix? Radio astronomers have detected jets of hot gas blasted out by a black hole in the galaxy at the heart of the Phoenix Galaxy Cluster, located 5.9 billion light-years away in the constellation Phoenix. This is an important result for understanding the coevolution of galaxies, gas, and black holes in galaxy clusters. phys.org Go to SourceRead More →

Microlensing measurement of a quasar’s accretion disk An active galactic nucleus (AGN) is a supermassive black hole residing at the core of a galaxy that is accreting material. The accretion occurs in the vicinity of the hot torus around the nucleus, and it can generate rapidly moving jets of charged particles that emit bright, variable radiation as material ccelertes as it falls inward. Quasars are perhaps the best-known luminous AGN, and their nuclei are relatively unobscured by dust. Quasar nuclear regions and disks are too far away and much too small to be resolved with telescopes and astronomers trying to understand the behavior of quasars,Read More →

Molecular outflow identified in the galaxy NGC 1482 Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers from Japan have probed a nearby starburst galaxy known as NGC 1482. They detected a molecular gas outflow that could be essential to improving the understanding of the galactic wind in NGC 1482. The finding is detailed in a paper published August 20 on arXiv.org. phys.org Go to SourceRead More →

Image: Hubble views edge of stellar blast While appearing as a delicate and light veil draped across the sky, this image from the NASA/ESA Hubble Space Telescope actually depicts a small section of the Cygnus supernova blast wave, located around 2,400 light-years away. The name of the supernova remnant comes from its position in the northern constellation of Cygnus (the Swan), where it covers an area 36 times larger than the full moon. phys.org Go to SourceRead More →

Scientists reveal complete physical scenario of sympathetic eruption of two solar filaments Solar filaments are large magnetic structures confining cool and dense plasma suspended in the hot and tenuous corona. phys.org Go to SourceRead More →

Space debris observed for the first time during the day On the afternoon of February 10, 2009, the operational communications satellite Iridium 33 collided with the obsolete Cosmos 2251 communications satellite over Siberia at an altitude of roughly 800 kilometers. The collision was at a speed of 11.7 kilometers a second and produced a cloud of more than 2,000 pieces of debris larger than ten centimeters. This debris spread out over an extensive area within a few months and has been threatening to collide with other operational satellites since then. This event was a wake-up call for all satellite operators, but also for politicians. “TheRead More →

NASA’s Webb solar array reconnects to the telescope One kilowatt is about what it takes to heat up some leftovers in a microwave—or to power the largest and most technically advanced telescope ever built. Thanks to its solar array, NASA’s James Webb Space Telescope will stay energy-efficient more than 1 million miles (1.5 million kilometers) from Earth. phys.org Go to SourceRead More →