A quasar is an extremely bright and distant point-like source visible to radio telescopes. The source is a so-called Active Galactic Nucleus, fueled by a supermassive black hole. Source: https://earthsky.org/astronomy-essentials/definition-what-is-a-quasar…
Tag: accretion
Cosmic ray originated in cataclysmic event
Astronomers found a high energy neutrino – a cosmic ray – that apparently originated during a “tidal disruption event,” that is, when a supermassive black hole shredded a distant star. Source: https://earthsky.org/space/origin-cosmic-ray-when-black-hole-shreds-star…
Water worlds may be abundant in our galaxy
A new study suggests that our Milky Way galaxy is filled with planets like Earth, containing continents and oceans. If so, life might be common in the Mlilky Way. Source: https://earthsky.org/space/water-common-on-planets-pebble-accretion-milky-way…
Maarten Schmidt solves the puzzle of quasars
On February 5, 1963, Maarten Schmidt unraveled the mystery of quasars and pushed back the edges of the known cosmos. His insight into quasars – the most distant and luminous objects known – has changed the way scientists view the universe. Source: https://earthsky.org/space/this-date-in-science-maartin-schmidt-discovers-first-known-quasar…
Researchers discover the earliest supermassive black hole and quasar in the universe
Nearly every galaxy hosts a monster at its center—a supermassive black hole millions to billions times the size of the Sun. While there’s still much to learn about these objects, many scientists believe they are crucial to the formation and structure of galaxies. What’s more, some of these black holes are particularly active, whipping up stars, dust and gas into glowing…
A new record for the most distant quasar
Astronomers have a new measurement for the distance of quasar J0313-1806, making it the new record-holder for the most distant quasar known. We’re seeing it just 670 million years after the Big Bang, or more than 13 billion light-years away. Source: https://earthsky.org/space/new-record-most-distant-quasar-black-hole-j0313-1806…
3-D simulation helps revealing accretion process in progenitor of tycho’s supernova
Dr. JIAO Chengliang from Yunnan Observatories of the Chinese Academy of Sciences, collaborating with Prof. XUE Li’s group from Xiamen University, performed three-dimensional (3-D) simulations of the accretion flow in the progenitor of Tycho’s supernova, which helps identifying the physical properties of the accretion process. Source: https://phys.org/news/2021-01-d-simulation-revealing-accretion-progenitor.html…
Black hole X-ray binary GRS 1915+105 has a variable magnetic disc wind, study suggests
Using NASA’s Chandra spacecraft, astronomers have performed high-resolution X-ray spectroscopic observations of a transient black hole X-ray binary known as GRS 1915+105. They report that the source exhibits a variable magnetic accretion disc wind. The study was detailed in a paper published December 16 on the arXiv pre-print repository. Source: https://phys.org/news/2020-12-black-hole-x-ray-binary-grs.html…
A planet-forming disk still fed by the mother cloud
Stellar systems like our own form inside interstellar clouds of gas and dust that collapse producing young stars surrounded by protoplanetary disks. Planets form within these protoplanetary disks, leaving clear gaps, which have been recently observed in evolved systems, at the time when the mother cloud has been cleared out. ALMA has now revealed an evolved protoplanetary disk with a large…
‘Strange rays’ crowdsourced on social media shed light on black hole illumination
Sparked by an image uploaded to Twitter, new research indicates that the light produced by black hole accretion may be bright enough to reflect off of dust, illuminating the host galaxy, and creating light and dark rays similar to the effect of crepuscular rays on Earth. The research is published in The Astrophysical Journal Letters. Source: https://phys.org/news/2020-11-strange-rays-crowdsourced-social-media.html…