Black holes can expel a thousand times more matter than they capture. The mechanism that governs both ejection and capture is the accretion disk, a vast mass of gas and dust spiraling around the black hole at extremely high speeds. The disk is hot and emits light as well as other forms of electromagnetic radiation. Part of the orbiting matter is…
Tag: Electromagnetic
CIA Declassifies Cold War-Era Plans for a ‘Nuclear Bird Drone’
“During the Cold War, the CIA considered building a bird-sized drone designed to spy on the communist bloc,” reports Popular Mechanics. “The drone would carry ‘black box’ spy packages into Russia and China, as well as take secret photographs — all while hiding in plain sight disguised as a bird…” The project envisioned a fleet of 12 bird-shaped drones, powered by…
Earth’s magnetic field may change faster than we thought
A long-standing question has been how fast Earth’s magnetic field can change. The authors of a new study say they’ve uncovered some answers. Source: https://earthsky.org/earth/earths-magnetic-field-change-faster-thought…
Solar Orbiter’s 1st views of the sun
Solar Orbiter’s new views are the closest images of the sun taken so far. Source: https://earthsky.org/space/solar-orbiters-first-views-of-the-sun…
Physicists say they’ve found a ‘tetraquark’
On July 1, scientists announced the discovery of a new exotic particle – a so-called “tetraquark” – a finding that marks a major breakthrough in a search of almost 20 years, carried out in particle physics labs all over the world. Source: https://earthsky.org/human-world/cern-physicists-discovery-new-particle-tetraquark…
For the 1st time, a visible light explosion from a black hole merger
In recent years, black hole mergers in our universe have been detected via ripples in spacetime known as gravitational waves. Now, for the first time, astronomers believe they’ve observed visible light from a black hole merger, in a peculiar 3-black-hole system. Source: https://earthsky.org/space/1st-time-visible-light-explosion-black-hole-merger…
Inferring the temperature structure of circumstellar disks from polarized emission
Polarized light is a familiar phenomenon because the scattering or reflection of light results in one of its two components being preferentially absorbed. The majority of sunlight on Earth, for example, is preferentially polarized due to scattering in the atmosphere (this helps make polarized sunglasses effective). Electromagnetic radiation from astrophysical sources can also be polarized, typically because of scattering from elongated…
Where neutrinos come from
Russian astrophysicists have come close to determining the origin of high-energy neutrinos from space. The team compared data on the elusive particles gathered by the Antarctic neutrino observatory IceCube and on long electromagnetic waves measured by radio telescopes. Cosmic neutrinos turned out to be linked to flares at the centers of distant active galaxies, which are believed to host supermassive black…
Future detectors to detect millions of black holes and the evolution of the universe
Gravitational-wave astronomy provides a unique new way to study the expansion history of the Universe. On 17 August 2017, the LIGO and Virgo collaborations first detected gravitational waves from a pair of neutron stairs merging. The gravitational wave signal was accompanied by a range of counterparts identified with electromagnetic telescopes. Source: https://phys.org/news/2020-04-future-detectors-millions-black-holes.html…
What are gravitational waves?
First postulated by Albert Einstein in 1916 but not observed directly until September 2015, gravitational waves are ripples in spacetime. Source: https://earthsky.org/space/definition-what-are-gravitational-waves…