Mullard Space Science Laboratory

Simulated galaxy composite / MSSL/UCL (background image NASA/HST)

ExoMars PanCam Field Trials / Andrew Griffiths/MSSL, UCL

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Aurora Borealis, Iceland, 2015 / Carlos Gauna

Introduction The Mullard Space Science Laboratory (MSSL), UCL’s Department of Space and Climate Physics, is the UK’s largest and most wide-ranging university space science group. We are based at Holmbury St Mary near Dorking in Surrey, and have around 175 people working on space science and engineering projects and research. In astrophysics, we study the extreme Universe, the life of galaxies and the nature of the Universe as a whole. In solar system science, we study our active Sun, solar wind & space weather, space plasmas, planetary science & imaging and climate extremes. Our scientific work is supported by excellent engineering staff and facilities, which allow us to lead and collaborate on missions from ESA (European Space Agency), NASA, Japan, Russia and China. Much of our work is through the UK and European Space Agencies. Our design offices, workshops, test and assembly facilities, environmental testing equipment and clean rooms allow the conception, build, test, calibration and delivery of space instrumentation to the highest international standard. Mullard Space Science Laboratory

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Artists’s impression of a Type Ia supernova / ESA/ATG medialab/C. Carreau

The extreme Universe Stars end their lives in extraordinary ways. Stars like the Sun end up as hot dense cores. Larger stars explode as supernovae, and their remnants are ultra-dense neutron stars. Even larger stars end their lives as black holes, after an immense cataclysm which generates gamma-rays detectable from the furthest reaches of the cosmos. MSSL investigates neutron stars and gamma-ray bursts using facilities in X-rays and the ultraviolet/optical – mostly instruments we’ve built for ESA’s XMM-Newton (X-ray Multi-Mirror Mission) and NASA’s Swift satellites. We are particularly interested in highly-magnetised neutron stars called magnetars, which emit spectacular outbursts of soft-gamma-rays, and in young hot neutron stars still cooling after their supernova. We use these objects to examine the physics of ultra-dense matter, and the extraordinary interaction of radiation and matter in the most extreme magnetic fields in the Universe. The novel technique of X-ray polarimetry is one of our current interests, as is the nature of the fireball resulting from the formation of the black hole, and whether there is a continuum of characteristics between supernovae and gamma-ray bursts. At the centres of at least most galaxies there are even larger black holes, millions of times more massive than those formed in stellar explosions. They lie at the focal point of the galaxy’s gravitational field, growing by taking in gas, stars, and stellar remnants. The strong gravity of these large but extremely dense objects shapes the space around them. The path that light takes is no longer straight, and as seen from a distant observer, the scene about them is distorted and multiplied. We calculate these effects, including absorption and scattering by intervening material in disks and clouds, to predict their signatures in our observations, and hence to arrive at the nature of the environments of black holes.

What happens to stars at the end of their lives? How does light travel near a black hole? What is the environment of black holes in active galaxies?

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The outline of our Galaxy, the Milky Way / ESA/Gaia

The life of galaxies The emission of energy from the region around black holes at the centre of galaxies disrupts the inflows from the external universe of gas which is the fuel for the next generations of stars. Supernova explosions and high velocity winds from young hot stars also drive out the interstellar gas from the galaxy, and these effects combine to choke off the formation of new stars. By examining the stellar populations, using, for example, spectroscopic surveys, and by fitting population models, we recreate the potential evolutionary paths of galaxies of different types and in different environments, to understand more about the general principles governing galaxy evolution. In particular we are interested in the relative importance of black holes and supernovae in this process. As much of the star formation occurs in dusty environments from previous generations of stars, this investigation requires >Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12

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