The Illustris project is an ongoing series of astrophysical simulations run by an international collaboration of scientists. The aim is to study the processes of galaxy formation and evolution in the universe with a comprehensive physical model. Early results are described in a number of publications following widespread press coverage. The project publicly released all data produced by the simulations in April, 2015. A followup to the project, IllustrisTNG, was presented in 2017.
Illustris Simulation
Overview
The original Illustris project was carried out by :de:Mark Vogelsberger|Mark Vogelsberger and collaborators as the first large-scalegalaxy formation application of Volker Springel's novel Arepo code. The Illustris project includes large-scale cosmological simulations of the evolution of the universe, spanning initial conditions of the Big Bang, to the present day, 13.8 billion years later. Modeling, based on the most precise data and calculations currently available, are compared to actual findings of the observable universe in order to better understand the nature of the universe, including galaxy formation, dark matter and dark energy. The simulation includes many physical processes which are thought to be critical for galaxy formation. These include the formation of stars and the subsequent "feedback" due to supernova explosions, as well as the formation of super-massive black holes, their consumption of nearby gas, and their multiple modes of energetic feedback. Images, videos, and other data visualizations for public distribution are available at .
Computational aspects
The main Illustris simulation was run on the Curie supercomputer at CEA and the SuperMUC supercomputer at the Leibniz Computing Center. A total of 19 million CPU hours was required, using 8,192 CPU cores. The peakmemory usage was approximately 25 TB of RAM. A total of 136 snapshots were saved over the course of the simulation, totaling over 230 TB cumulative data volume. A code called "Arepo" was used to run the Illustris simulations. It was written by Volker Springel, the same author as the GADGET code. The name is derived from the Sator Square. This code solves the coupled equations of gravity and hydrodynamics using a discretization of space based on a moving Voronoi tessellation. It is optimized for running on large, distributed memory supercomputers using a MPI approach.
In April, 2015 the project team publicly released all data products from all simulations. All original data files can be directly downloaded through the . This includes group catalogs of individual halos and subhalos, merger trees tracking these objects through time, full snapshot particle data at 135 distinct time points, and various supplementary data catalogs. In addition to direct data download, a web-based API allows for many common search and data extraction tasks to be completed without needing access to the full data sets.
German postage stamp
In December 2018, the Illustris simulation was recognized by Deutsche Post through a special series :File:Stamp_illustris.jpg|stamp.
IllustrisTNG
Overview
The , "the next generation" follow up to the original Illustris simulation, was first presented in July, 2017. The project was achieved by a team of scientists from Germany and the U.S. led by :de:Volker Springel|Prof. Volker Springel. First, a new physical model was developed, which among other features now includes Magnetohydrodynamics. Three simulations are planned, which are different volumes at different resolutions. The intermediate simulation is equivalent to the original Illustris simulation. Unlike Illustris, it was run on the Hazel Hen machine at the High Performance Computing Center, Stuttgart in Germany. Up to 25,000 computer cores were employed.
Public data release
In December 2018 the simulation data from IllustrisTNG was released publicly. The data service includes a JupyterLab interface.
