Max Planck Institutes and Experts

A team led by astronomers from the MPI for Astronomy has created the first three-dimensional map of the "adolescent" Universe, just 3 billion years after the Big Bang. Applying a new technique analogous to x-ray computer-tomographic (CT) imaging, the researchers measured the light from a dense grid of distant background galaxies probing the Universe from multiple locations, and then constructed a 3D map of the intervening matter. This map, millions of light years across, provides a tantalizing glimpse of large structures in the "cosmic web", which forms the backbone of cosmic structure.

Astronomers have presented the first detailed study of the atmospheric features – the extraterrestrial wea ther patterns – of a brown dwarf (an intermediate object between planet and star). The results include the first surface map of a brown dwarf and measurements at different wavelengths probing its atmosphere at different depths. They mark the beginning of an era in which astronomers will be able to compare models for cloud formation on brown dwarfs – and, eventually, on giant gas planets in distant star systems – with observations.

Latest three-dimensional computer simulations are closing in on the solution of an decades-old problem: how do massive stars die in gigantic supernova explosions? Since the mid-1960s, astronomers thought that neutrinos, elementary particles that are radiated in huge numbers by the newly formed neutron star, could be the ones to energize the blast wave that disrupts the star. However, only now the power of modern supercomputers has made it possible to actually demonstrate the viability of this neutrino-driven mechanism.

By combining data for more than 250,000 individual objects, an MPA-based team has for the first time been able to measure X-ray emission in a uniform manner for objects with masses ranging from that of the Milky Way up to that of rich galaxy clusters. The results are surprisingly simple and give insight into how ordinary matter is distributed in today's universe, and how this distribution has been affected by energy input from galactic nuclei.

Phase field models are a crucial tool in the modeling of complex phenomena. In this context, simulation can help to avoid or reduce the number of costly experiments. For this it is necessary to work with efficient algorithms. Here, we describe iterative solvers that deal with the discretized differential equation models and thus allow for an accurate solution of the problems.