Galaxies

The dwarf galaxy IC 1613 photographed by the OmegaCAM on ESO's VST (Image ESO)

The OmegaCAM camera mounted on ESO’s VST (VLT Survey Telescope) was used to take a picture of the dwarf galaxy IC 1613. It has the distinction of being really clean, meaning that it contains very little dust while most galaxies contain dust clouds or are even full of it. The very low dust content of IC 1613 allows astronomers to observe its inside and is therefore an excellent target for astronomy and astrophysics studies.

The Abell 1689 galaxy cluster

An article published in the journal “Physical Review Letters” offers clues about the link between the internal structure of a galaxy cluster and the dark matter environment surrounding it. The study of dark matter is complex because it can only be done indirectly due to the fact that we can’t detect it directly. Until now, scientists believed that the greater the mass of a cluster the greater the amount of dark matter in its environment. This new research suggests that things are more complicated.

Artistic concept of the quasar galaxy W2246-0526 (Image NRAO/AUI/NSF; Dana Berry / SkyWorks; ALMA (ESO/NAOJ/NRAO))

The ALMA radio telescope allowed us to study the extraordinary events taking place in the galaxy W2246-0526, the brightest we know. It’s a quasar because its core is powered by a supermassive black hole that has a considerable activity that generates enormous jets of particles and high-energy radiation. This one in particular is part of a special category of quasars because it’s full of dust that absorbs a lot of radiation. However, the consequence of this activity is a turbulent activity that is expelling the gas.

The galaxy NGC 4845 photographed by the Hubble Space Telescope (Image ESA/Hubble & NASA and S. Smartt (Queen's University Belfast))

The Hubble Space Telescope took a photograph of the galaxy NGC 4845. At its core, it contains a supermassive black hole, a fact now considered normal but that can be detected only indirectly, through the gravitational effects on stars near to the galactic core. During the observations, it swhoed a remarkable appetite as in 2013 it swallowed in a short time a mass several times that of the planet Jupiter.

The galaxy NGC 6052 photographed by the Hubble Space Telescope (Image ESA/Hubble & NASA, Acknowledgement: Judy Schmidt)

NGC 6052 is a galaxy apparently abnormal because of its odd shape. It was initially classified in that way but later astronomers realized that it’s actually the result of an ongoing merger of two galaxies with similar masses. The Hubble space telescope was used to take a picture of NGC 6052 with its Wide Field Planetary Camera 2 (WFPC2), which includes observations in visible and ultraviolet light.