Astronomers Describe Their Discovery of “Alcyoneus” -The Largest Galaxy in the Universe

 

Galaxy Alcyoneus

 

One of the main questions the discovery of a giant radio galaxy (GRG) –active galactic nuclei that are very luminous at radio wavelengths– named Alcyoneus, after the son of the primordial Greek god of the sky, Ouranos, directly triggered is: “Why has Alcyoneus grown to such a large size,” asked astronomer Reinout van Weeren at the Leiden Observatory in an email to The Daily Galaxy. “The host galaxy of Alcyoneus and its central massive black hole have properties that are rather typical for radio galaxies,” van Weeren explained. “So Alcyoneus is not really special in this way. It is likely that Alcyoneus’ cosmic environment has played a role in allowing it to grow to its enormous size.

(more…)

Hidden Supermassive AGN Among the Brightest and Most Enigmatic Objects in the Universe 

Galaxy Messier 77 AGN

 

The European Southern Observatory’s Very Large Telescope Interferometer (ESO’s VLTI) on the Paranal Mountain in the Atacama Desert of northern Chile has observed a cloud of cosmic dust at the center of the galaxy Messier 77 that is hiding a supermassive black hole. The findings have confirmed predictions made around 30 years ago and are giving astronomers new insight into “active galactic nuclei (AGN)” –some of the brightest and most enigmatic objects in the universe.

(more…)

“Three Supermassive Monsters” –At the Core of One of the Largest Galaxies in the Universe (Weekend Feature)

NGC 6240

 

Massive galaxies like our Milky Way and Andromeda typically consist of hundreds of billions of stars and host a single, central black hole with a mass of several million up to several 100 million solar masses at their centers. In 2019, an international research team led by scientists from Göttingen and Potsdam proved for the first time that the irregular galaxy NGC 6240, the Starfish Galaxy, contains three supermassive black holes, the remnant of mergers between three smaller galaxies.

(more…)

Dark-Matter Asteroids  – “Trillions of Trillions May Exist in the Milky Way”

Dark Matter Asteroids

 

“Dark matter holds the key to understanding the universe,” says astrophysicist Paul Davies. The mysterious dark matter particles compose 80% of the matter in the Universe, and they have been described as ranging from planet-sized particles to dark-matter life.

(more…)

Why Were the Earliest Galaxies In the Universe Brighter Than Those We See Today?

 

First Galaxies

 

“We did not expect that Spitzer, with a mirror no larger than a Hula-Hoop, would be capable of seeing galaxies so close to the dawn of time,” said Michael Werner, Spitzer’s project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California in 2019. “But nature is full of surprises, and the unexpected brightness of these early galaxies, together with Spitzer’s superb performance, puts them within range of our small but powerful observatory.”

(more…)

One of the Last Great Mysteries of the Early Universe

Black Hole of Early Universe

 

Did supermassive black holes exist shortly after the big bang, before the birth of stars? “This is one of the last great mysteries of the early universe,” said Kirk S. S. Barrow in 2018, currently at Harvard’s CfA, about how supermassive black holes formed during the birth of a galaxy. It’s a mystery the James Webb Space Telescope (JWST) may soon be able to solve.

(more…)