The new data release of ESA’s Gaia satellite, published today, not only includes data that allows astronomers to compute accurate distances for 1.33 billion stars. Researchers based at the Max Planck Institute for Astronomy have also used Gaia’s measurements to derive the physical properties of almost 80 million stars, making this the largest stellar census yet. At the same time, the analysis provides the most detailed three-dimensional map of dust in our home galaxy yet, which promises to put the analysis of celestial objects on a more solid footing than before. [more]

Astronomers have investigated a small population of stars in the halo of the Milky Way Galaxy, finding its chemical composition to closely match that of the Galactic disk. This similarity provides compelling evidence that these stars have originated from within the disc, rather than from merged dwarf galaxies. The reason for this stellar migration is thought to be theoretically proposed oscillations of the Milky Way disc as a whole, induced by the tidal interaction of the Milky Way with a passing massive satellite galaxy. [more]

Astrophysicists from Heidelberg, Garching, and the USA gained new insights into the formation and evolution of galaxies. They calculated how black holes influence the distribution of dark matter, how heavy elements are produced and distributed throughout the cosmos, and where magnetic fields originate. This was possible by developing and programming a new simulation model for the universe, which created the most extensive simulations of this kind to date.First results of the "IllustrisTNG" project have now been published in three articles in the journal Monthly Notices of the Royal Astronomical Society. These findings should help to answer fundamental questions in cosmology. [more]

The motions of stars in a galaxy are like a history book, yielding information about how the galaxy has grown over time. Now a group of astronomers has assembled a library of such galaxy history books. Their data for 300 galaxies showcases the diversity of the various ways different galaxies came into being over the past billions of years. This is the first large-scale library of galactic histories, and it is particularly important for astronomers running simulations of cosmic structure formation – since those simulations can now be checked against a large set of observations. The results have been published in the journal Nature Astronomy on January 1, 2018. [more]

Astronomers have found the first direct observational evidence for a long-suspected link between galaxies' central black holes and the rate at which stars form throughout a galaxy's history. To this end, the astronomers made use of a survey of black hole masses and reconstructed each galaxy's star formation history from its spectrum. Black hole mass and star formation rate were clearly linked, confirming a connection that had been assumed to exist for a considerable time. The results have been published in the journal Nature. [more]