Accretion tagged posts

Black hole size revealed by its eating pattern

An artist’s impression of an accretion disk rotating around an unseen supermassive black hole. The accretion process produces random fluctuations in luminosity from the disk over time, a pattern found to be related to the mass of the black hole in a new study led by University of Illinois Urbana-Champaign researchers.
Graphic courtesy Mark A. Garlick/Simons Foundation

The feeding patterns of black holes offer insight into their size, researchers report. A new study revealed that the flickering in the brightness observed in actively feeding supermassive black holes is related to their mass.

Supermassive black holes are millions to billions of times more massive than the sun and usually reside at the center of massive galaxies...

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Supermassive Black Holes Devour Gas just like their Petite Counterparts

black hole
As a supermassive black hole consumed a star, researchers were surprised it exhibited properties that were similar to that of much smaller, stellar-mass black holes.
Credits:Image: Christine Daniloff, MIT

On Sept. 9, 2018, astronomers spotted a flash from a galaxy 860 million light years away. The source was a supermassive black hole about 50 million times the mass of the sun. Normally quiet, the gravitational giant suddenly awoke to devour a passing star in a rare instance known as a tidal disruption event. As the stellar debris fell toward the black hole, it released an enormous amount of energy in the form of light.

Researchers at MIT, the European Southern Observatory, and elsewhere used multiple telescopes to keep watch on the event, labeled AT2018fyk...

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The Brightest, Furthest Pulsar in the universe

NGC 5907 X-1: record-breaking pulsar

NGC 5907 X-1: record-breaking pulsar

ESA’s XMM-Newton has found a pulsar the spinning remains of a once-massive star that is a 1000X brighter than previously thought possible. The pulsar is also the most distant of its kind ever detected, with its light travelling 50 million light-years before being detected by XMM-Newton. Pulsars are spinning, magnetised neutron stars that sweep regular pulses of radiation in two symmetrical beams across the cosmos. If suitably aligned with Earth these beams are like a lighthouse beacon appearing to flash on and off as it rotates. They were once massive stars that exploded as a powerful supernova at the end of their natural life, before becoming small and extraordinarily dense stellar corpses.
This X-ray source is the most luminous of its type detected to...

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Why Earth is so much bigger than Mars: Rocky Planets formed from ‘Pebbles’

Southwest Research Institute scientists developed a new process in planetary formation modeling that explains the size and mass difference between the Earth and Mars. Mars is much smaller and has only 10 percent of the mass of the Earth. Conventional solar system formation models generate good analogs to Earth and Venus, but predict that Mars should be of similar-size, or even larger than Earth. Credit: Image Courtesy of NASA/JPL/MSSS

Southwest Research Institute scientists developed a new process in planetary formation modeling that explains the size and mass difference between the Earth and Mars. Mars is much smaller and has only 10 percent of the mass of the Earth. Conventional solar system formation models generate good analogs to Earth and Venus, but predict that Mars should be of similar-size, or even larger than Earth. Credit: Image Courtesy of NASA/JPL/MSSS

Using a new process in planetary formation modeling, where planets grow from tiny bodies called ‘pebbles,’ scientists can explain why Mars is so much smaller than Earth. This same process also explains the rapid formation of the gas giants Jupiter and Saturn, as reported earlier this year.

“This numerical simulation actually reproduces the structure of the in...

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