accretion disk tagged posts

New UNLV-led research is helping to unravel clues to a cosmic mystery that has eluded scientists for decades. Cataclysmic variables (CVs) are binary star systems in which primary stars—incredibly dense and compact white dwarfs—accumulate material from nearby companion stars. The material spirals in towards the white dwarf through what is known as an accretion disk. These deep space systems are responsible for a number of cosmic phenomena, including sudden bursts of light known as classical novae that temporarily appear to resemble new stars before fading away over time.

A long-standing mystery in cataclysmic variables
Modern astronomical instruments have enabled scientists to understand many of the mechanisms that drive CVs...

The discovery of strange, ultra-red objects—especially the extreme case known as The Cliff—has pushed astronomers to propose an entirely new type of cosmic structure: black hole stars. These exotic hybrids could explain rapid black hole growth in the early universe, but their existence remains unproven.

In the summer of 2022, only a few weeks after the James Webb Space Telescope (JWST) began delivering its first scientific images, astronomers noticed an unexpected pattern: tiny red points scattered throughout the new observations. These extremely compact, distinctly red objects appeared with remarkable clarity thanks to JWST’s sensitivity, and there were far more of them than expected...

A team of astrophysicists led by Caltech has managed for the first time to simulate the journey of primordial gas dating from the early universe to the stage at which it becomes swept up in a disk of material fueling a single supermassive black hole. The new computer simulation upends ideas about such disks that astronomers have held since the 1970s and paves the way for new discoveries about how black holes and galaxies grow and evolve.

“Our new simulation marks the culmination of several years of work from two large collaborations started here at Caltech,” says Phil Hopkins, the Ira S...

An international team of astronomers observed the second one of the two supermassive black holes circling each other in an active galaxy OJ 287.

Supermassive black holes that weigh sever...