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Research Fellows Directory

Mark Gieles

Professor Mark Gieles

Research Fellow


University of Surrey

Research summary

We do not know how our Milky Way came to be. My research aims to shed

light on this problem by interrogating some key witnesses: the

mysterious globular clusters. These densely packed stellar systems

contain millions of stars held together by gravity. Despite their

ubiquity and their importance for astrophysics, the details of how

they formed in the context of the formation of the Milky Way itself

are still shrouded in mystery. The Milky Way contains about 150

globular clusters, which are almost as old as the Universe, meaning

that they formed as one of the first building blocks of our

Galaxy. Understanding the evolution of globular clusters is essential

to understand the Milky Way.

In the next decade astronomers are going to make a giant leap in

unravelling the birth and growing up of the Milky Way and its globular

clusters. In November 2013 the ESA-Gaia space telescope was launched:

it will make a multi-dimensional map of a billion stars in the Milky


To make sense of this amazing data, I run computer simulations of the

gravitational attraction between all the stars in globular clusters

and the matter in the Milky Way. What is unique is that, for the first

time, the simulations consider simultaneously the evolution of the globular

cluster stars and the evolution of the Milky Way in an expanding

Universe. These models can soon be compared to Gaia data to learn

about dark matter, black holes and ultimately the formation of the

Milky Way.

Interests and expertise (Subject groups)

Grants awarded

The origin of the Milky Way globular clusters

Scheme: University Research Fellowship

Dates: Jan 2015 - Dec 2017

Value: £302,690.23

Globular Clusters: Tracers of Galaxy Evoution

Scheme: University Research Fellowship

Dates: Mar 2010 - Dec 2014

Value: £437,961.17