How to Surf the Stars

Wednesday 18th October at 19.00hrs

Location: Aula Prima, University of Malta – Valletta Campus

Registration required (see link below).


Since the discovery of disc galaxies by Edwin Hubble in the 1920s, it has been assumed that stars born at one radius within a galaxy continue orbiting it at that radius, maybe with a growing, but relatively small radial oscillation that takes it to nearby smaller and larger radii. But we now know that the spiral arms present in most disc galaxies are a form of wave travelling across the galaxy.

Stars can surf these spiral waves, much like a surfer on an ocean wave, or a dolphin on a ship’s wake. As a result the stars can move around to very different radii than where they were born. This talk will discuss some of the consequences of this “radial migration” and present evidence that has occurred within our own galaxy, the Milky Way.

The Speaker

Victor Debattista crossed the Atlantic to earn his BSc from NYU and his PhD from Rutgers University in 1998. He then crossed the Atlantic again for postdocs at the University of Basel and ETH Zurich (both in Switzerland). At that point he crossed the Atlantic again to take up a Brooks Prize Fellowship at the University of Washington.

In 2007 he decided to cross the Atlantic one last time to take up a RCUK Fellowship at the University of Central Lancashire, where in the meantime he has been appointed Professor of Astrophysics.


Cover Image

A simulated galaxy exhibiting spiral arms. Right: An image of an actual spiral galaxy (M101) acquired with ISSA’s astronomical observatory in Gozo. (Left image: Victor Debattista; right image: Joseph Caruana.)