UCL Astrophysics Consolidated Grant 2012-2015

In the last twenty-five years, the world of astronomy has been turned upside down. We now know that not only is our universe expanding, but that it is expanding at an ever-increasing rate. Fuelled by a mysterious driver called Dark Energy - galaxies, such as our Milky Way, are rushing away from each other at such enormous acceleration that not even the powerful force of gravity can hold the universe together. The researchers of UCL's Astrophysics Group are putting to the test these discoveries with their ambitious programme of research for the coming years. A map of 300 million galaxies that astronomers will put together using the Dark Energy Survey over the next decade will be combined with a new chart of the Cosmic Microwave Background from the Planck satellite to understand the conditions in the early universe, to detect the tiny mass of the Neutrino particle and to test Einstein's theory of general Relativity on the largest scales. At the other end of the astronomical scale, 25 years ago we knew only of the planets in our own Solar System - eight by today's count, with minor planets like Pluto, Charon and Ceres, along with asteroids and comets. Today the score is over 2000 and counting, thanks to the discovery of extra-solar planets, i.e. planets orbiting stars other than our own Sun. So are these "exo-planets" like the ones we already know? Are these exoplanet systems like our planetary system? So far, the answer is "no", and UCL's programme also contains projects to find out just what exo-planets are like, what their atmospheres are made of, and how they behave in conditions very different from those affecting our Earth and its nearest neighbours. And in between these two extremes, our projects will probe the giant magnetic fields that surround planets like Jupiter and Saturn, and how these interact with the planet's atmosphere. Exo-planets may also have such magnetic fields; knowing how they work in our Solar System will help us understand and even detect exo-planetary systems. We will probe just how stars and the planets around them form from vast gas and dust clouds, and how the chemistry that goes on between the stars affects and controls those crucial processes. UCL's astrophysics team will also look at the death of stars in giant explosions called supernovas and how, in dying, huge stars pour their hearts back out into the galaxy, enriching them with the gas, dust and chemical soups required to make new stars, new planets and even new life. None of this can be done unless astronomers continually improve the equipment - the telescopes and their detectors - with which they carry out their studies of the heavens. So UCL's instrument makers will create ever-more sensitive detectors and spectrometers, with better and better optical surfaces, with which to equip the next generation of telescopes and space missions. And astronomers need to model the universe they study with ever more complex mathematical techniques. So UCL's computer experts will generate the sophisticated models, running on the university's supercomputers, to generate the basic molecular data needed, and simulate the conditions in the early universe, the evolving galaxies and the stars and planetary systems that inhabit them. But all of this will be wasted unless our fellow citizens get to share in the wonder and excitement of our group's work. So Astrophysics@UCL will ensure that its members continue to explain their work through talks and lectures, through public events, and through the media, inspiring the next generation of scientists, helping and challenging industry to develop new technologies, and ensuring that our understanding of the universe becomes ever deeper and wider.