quasar tagged posts

Cosmic Simulation Reveals How Black Holes Grow and Evolve

This still shows an accretion disk around a supermassive black hole.
This still from the simulation shows a supermassive black hole, or quasar, surrounded by a swirling disk of material called an accretion disk. Credit: Caltech/Phil Hopkins group

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...

Read More

Observations Explore Radio Jet of a Powerful Quasar

Observations explore radio jet of a powerful quasar
VLBI image of PKS 2215+020 at 1.7 GHz. Credit: Universe (2024). DOI: 10.3390/universe10020097

European astronomers have conducted very long baseline interferometric (VLBI) observations of a radio jet structure in a powerful quasar known as PKS 2215+020. The collected VLBI data provide important insights into the properties of this jet, suggesting that PKS 2215+020 is a blazar. The findings were presented February 17 in the Universe journal.

Quasars, or quasi-stellar objects (QSOs) are active galactic nuclei (AGN) of very high luminosity, emitting electromagnetic radiation observable in radio, infrared, visible, ultraviolet and X-ray wavelengths.

They are among the brightest and most distant objects in the known universe, and serve as fundamental tools for numerous studies in as...

Read More

Gas on the run – ALMA spots the Shadow of a Molecular Outflow from a Quasar when the Universe was less than one billion years old

The molecular gas outflow from the quasar includes hydroxyl (OH) (top). Due to the motion of the molecular gas toward the observer, the OH peak in the absorption spectrum (bottom, dashed blue line) appears at a shorter wavelength (solid blue line), a phenomenon known as the Doppler effect. (Illustration: ALMA (ESO/NAOJ/NRAO) modified from Dragan Salak, et al. The Astrophysical Journal. February 1, 2024)
The molecular gas outflow from the quasar includes hydroxyl (OH) (top). Due to the motion of the molecular gas toward the observer, the OH peak in the absorption spectrum (bottom, dashed blue line) appears at a shorter wavelength (solid blue line), a phenomenon known as the Doppler effect. (Illustration: ALMA (ESO/NAOJ/NRAO) modified from Dragan Salak, et al. The Astrophysical Journal. February 1, 2024)

Theoretical predictions have been confirmed with the discovery of an outflow of molecular gas from a quasar when the Universe was less than a billion years old.

A quasar is a compact region powered by a supermassive black hole located in the center of a massive galaxy.

They are extremely luminous, with a point-like appearance similar to stars, and are extremely distant from Earth...

Read More

Unexpected Chemistry reveals Cosmic Star Factories´ Secrets

Galaxy illustration with molecules
Light from many different molecules reveals the secrets of distant star factories. This illustration shows the many molecules found in the quasar APM 08279+5255, together with a Hubble telescope image of a similar galaxy in the nearby universe, IC 5063, which also has an active supermassive black hole at its centre. Background image credits: NASA, ESA & W. P. Maksym (CfA); Jmol (molecules); R. Cumming (montage)Photographer: NASA, ESA & W. P. Maksym (CfA); Jmol (molecules); R. Cumming (montage)

Two galaxies in the early universe, which contain extremely productive star factories, have been studied by a team of scientists led by Chalmers University of Technology in Sweden...

Read More