Black holes

The dual quasar SDSS J141637.44+003352.2

0

An article published in “The Astrophysical Journal” reports the confirmation of three pairs of supermassive black holes in close proximity to the point that we will see them merge in a future that is near from an astronomical point of view. A team of researchers led by Dr. John Silverman of the Kavli Institute for the Physics and Mathematics of the Universe used three observatories on Mount Maunakea in Hawaii: the Subaru Telescope, the Keck Observatory, and the Gemini Observatory to examine a huge amount of quasars in search of traces of a dual center, and among 421 candidates they confirmed three. These are rare cases, to the point that the estimate is that 0.3% of quasars are dual with two supermassive black holes on a collision course.

The galaxy NGC 1365 seen by MUSE (Image ESO/TIMER survey)

0

ESO has published an image of the galaxy NGC 1365, also known as The Great Barred Spiral Galaxy, captured with the MUSE instrument mounted on the VLT in Chile. The nickname is due to its particular shape with two structures running from its center that extend to its borders. It’s an uncommon type of galaxy since about 15% of galaxies belong to it while spiral ones are common. In this case, there’s a second bar inside the main one. The observations conducted with MUSE will help to understand the dynamics of the stars within NGC 1365 and its supermassive black hole.

The star S4711 (Image courtesy Florian Peißker et al.)

0

Two articles published in “The Astrophysical Journal” report research on stars orbiting Sagittarius A*, or simply Sgr A*, the supermassive black hole at the center of the Milky Way, including the ones that reach the highest speed, S62 and S4714, and the one that goes through the orbit in the shortest time, S4711 in 7.6 Earth years. A team of researchers from the German University of Cologne led by Florian Peißker used observations made with the NACO and SINFONI instruments mounted on ESO’s VLT in Chile to track S62’s orbit. With the addition of two more researchers, the team also tracked the orbits of other stars in that area.

Chandra Deep Field-South with the 28 heavily obscured supermassive black holes

0

An article published in “The Astrophysical Journal” reports the discovery of 28 heavily obscured supermassive black holes. A team led by Erini Lambrides of Johns Hopkins University combined over 80 days of observations of NASA’s Chandra space telescope in the survey known as Chandra Deep Field-South (CDF-S) with the ones of other telescopes that include Hubble and Spitzer to identify active galactic nuclei whose emissions at many wavelengths were blocked by the huge cocoon of materials that surrounds them. The heavily obscured supermassive black holes are among the most sought after because understanding their growth mechanisms helps to understand the evolution of these extreme objects that can have masses even billions of times the Sun’s.

Artist's concept of Pōniuāʻena (Image courtesy International Gemini Observatory/NOIRLab/NSF/AURA/P. Marenfeld)

0

An article accepted for publication in “The Astrophysical Journal Letters” reports the discovery of a very bright primordial quasar that was cataloged as J100758.264+211529.207, or simply J1007+2115, and named Pōniuāʻena. A team of researchers used three Mount Maunakea Observatories in Hawaii to identify one of the oldest known quasars, surpassed in age only by the one cataloged as J1342+0928, whose discovery was announced in December 2017.

From Earth we see Pōniuāʻena as it was about 13 billion years ago, a quasar powered by a supermassive black hole with an estimated mass of 1.5 billion times that of the Sun, almost twice the one that powers J1342+0928. This raises more than ever the problem of the quick growth of some primordial supermassive black holes.