Observational evidences suggest a co-evolution of the central supermassive black holes and their host galaxies. In some of them, the black hole is ingesting the material surrounding it at a very high rate, emitting a large quantity of energy. In those cases we say that the galaxy has an active nucleus (AGN). Studying the mechanisms which control the relation between the active nucleus and the rest of the galaxy is essential to understand how these objects form and evolve, and to be able to throw light on this question we need to compare active and non-active galaxies. Here, we first identify
This section includes scientific and technological news from the IAC and its Observatories, as well as press releases on scientific and technological results, astronomical events, educational projects, outreach activities and institutional events.
Large scale dynamical differences between active and non-active galaxies in the local UniverseAdvertised on
Is the Large Magellanic Cloud spiral arm a stable structure?
Some galaxies in the Universe display beautiful and appealing features known as "spiral arms". However, not all galaxies show spiral arms in the same manner. Among the variety of cases the Large Magellanic Cloud (LMC), a dwarf galaxy infalling towards the Milky Way, stands out. The LMC is the prototype of an entire family of galaxies, the Magellanic Spirals that are characterised by the presence of a barred stellar structure near their centres and a single spiral arm. Spiral patterns can form after galactic collisions, with subsequent star formation piling up in these arms. Nevertheless, weAdvertised on
The impact of strong recombination on temperature determination in planetary nebulae
The long-standing difference in chemical abundances determined from optical recombination lines and collisionally excited lines raises questions about our understanding of atomic physics, as well as the assumptions made when determining physical conditions and chemical abundances in astrophysical nebulae. Here, we study the recombination contribution of [O III] 4363 and the validity of the line ratio [O III] 4363/4959 as a temperature diagnostic in planetary nebulae with a high abundance discrepancy. We derive a fit for the recombination coefficient of [O III] 4363 that takes into accountAdvertised on
The first “ultrahot Neptune” is discovered
A team of astronomers from the University of Chile, in collaboration with the Instituto de Astrofísica de Canarias (IAC) and the University of La Laguna (ULL), has discovered the first “ultrahot Neptune”, which is in orbita round the nearby star LTT 9779. The planet is so close to its star that its year lasts only 19 hours, and the star’s radiation heats the planet to more than 1,700 degrees centigrade. At those temperaturas, the heavy elements such as iron can be ionized in the atmosphere and molecules can dissociate, which makes this a unique laboratory for studying the chemistry ofAdvertised on
Exogeneous material found on the surface of asteroids Ryugu and Bennu
The two near-Earth asteroids Ryugu and Bennu, primary targets of the Hayabusa2 (JAXA) and OSIRIS-REx (NASA) space missions, keep surprising us. In two companion papers presented in Nature Astronomy, researchers have found exogenous bright material scattered across the asteroids’ surfaces. Members of the Solar System Group of the Instituto de Astrofísica de Canarias (IAC) have contributed to this discovery, in particular Dr. Eri Tatsumi, who is the first author of the paper presenting findings on Ryugu (Hayabusa2).Advertised on
Astronomy and Literature, together again in La Palma
In the III Hispano-American Writers’ Festival, which is being celebrated in Los Llanos de Aridane (La Palma), three authors and two astrophysicists participated yesterday, Thursday, in a panel discussion on the theme “Looking at what no longer exists”. During the morning, a small group of those invited to the Festival, in which the Instituto de Astrofísica de Canarias is collaborating, visited the Roque de Los Muchachos Observatory in Garafía, satisfying the necessary health and security measures against COVID-19.Advertised on