Video Friday: Illustris Cosmological Simulation Predicts Galaxy Formation
With the Illustris Simulation, astrophysicists have accurately modeled the correct mix of spiral, elliptical and irregular galaxies to show the origins of all elements more complex than hydrogen and helium.
Learn more about the Illustris simulation at there home page here. Illustris is a cosmological hydrodynamical simulation which enables the comparison of predictions to astronomical measurements of the universe.
Illustris reproduces a range of observable properties of galaxies and the relationships between these properties. Galaxies in the simulation have the appropriate amounts of neutral hydrogen gas, molecular gas, and “metals” (all elements other than hydrogen and helium). Illustris supports modeling of “satellite” galaxies, which are galaxies which orbit in the gravitational influence of a much larger, nearby galaxy. e.g. our own Local Group. The model predicts changes in internal structure as galaxy populations evolve and includes the impact of gas on the structure of dark matter. using the Illustris simulation to produce “mock” observations which then may be compared to real observations. For example, light is emitted from stars at various wavelengths, and in the simulation physical properties of the stars are emulated allowing a synthetic or “mock” observation to be calculated. The simulation has been used, for example, to recreate the iconic Hubble Space Telescope “Ultra Deep Field” image.
The image below is half the real Hubble Ultra Deep Field telescope image and the other half a synthetic prediction from the Illustris model.