White dwarfs are the simplest stars with the simplest surface chemical compositions 
known.  Spectroscopically we detect only hydrogen in surfaces of the vast majority 
of these stars.  The remainders are of various types, including stars with surfaces 
of nearly pure helium and some apparently massive stars with carbon and oxygen at 
the photosphere.

We will examine the potential offered by the white dwarf stars in the context of 
both astrophysics and physics.

I will discuss recent high resolution radio observations of several molecular clouds 
in the centre of our Galaxy. In particular, we are interested in understanding the 
detailed properties of the molecular gas, which may be transformed into stars. This 
process maybe quite different in the Galactic centre, where the environment is
extreme and the physical conditions are more different than in the Solar neighborhood.

There is much to be learned about galaxy formation and evolution from our own Milky 
Way halo and the dwarf galaxies around it. Resolved stellar spectroscopy presents us 
with “archaeological” evidence about the chemical enrichment of the interstellar 
medium back to the earliest times. In this talk I will review several insights in the 
(chemical) evolution of the dwarf galaxies around the Milky Way from both modeling
and observational perspectives.

The observed thermal properties of the intracluster medium in galaxy groups and 
clusters show much more dispersion than expected if the gas was heated only by 
shocks associated with accretion and mergers.  In this talk, I will review
ongoing efforts to understand these findings. The most common assertion is that 
the diversity is the result of the tremendous energy output from supermassive 
black holes hosted by galaxies destined to become cluster members, both before 
and after cluster formation.

Over 70 galaxies are now know to reside within the Local Group, all but a few of which are classified as dwarfs. This marks an increase of more than a factor of 2 in less than 10 years, with the Sloan Digital Sky Survey (SDSS) and the Pan-Andromeda Archeaological Survey (PAndAS) having provided the majority of these discoveries. I will review the properties of these systems, with particular emphasis on results from PAndAS.

In this talk, I will describe some recent developments at the intersection of 
statistics and computer science motivated by 'big data' applications. In particular, 
I will talk about Sequential Monte Carlo (SMC), an increasingly popular complement 
to Markov chain Monte Carlo methods. Among other advantages, SMC algorithms are 
easier to parallelise.

Over 400 refereed science papers have been published based on data from the Keck adaptive optics (AO) systems. This colloquium will provide an overview of the AO science product and the technical developments behind this and future high angular resolution science at Keck Observatory.

Direct imaging is the new frontier in exoplanet detection and the means by which we will eventually discover a true Earth twin around a Sun-like star.  In this talk, I introduce the new observing techniques/powerful image processing methods used to directly image planets as well as some of the surprising properties of the first directly imaged planetary systems (e.g. HR 8799 and Fomalhaut) in particular their atmospheres/sources of

Debris disks are disks of dust that surround a significant fraction of stars of a wide range of masses and ages. From dust lifetime arguments it is inferred that these dust particles originate from the collision/sublimation of planetesimals, similar to the asteroids, comets and Kuiper belt objets in our Solar System. We review results from Spitzer and Herschel debris disks surveys regarding the disk frequency,

Strong dynamical interactions between planetoids and planets can place large bodies on eccentric and/or inclined orbits.  If gas is present during scattering events, a wide range of nebular shocks will be produced.  Any solids that pass through these shocks can be significantly altered by rapid melting followed by crystallization during cooling. Some of the resulting solids should be incorporated into meteoritic parent