Understanding Origins at the Open University (UO@OU)

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Our research project is called Understanding Origins at the Open University; the origins that we wish to study are those of the Solar System, and how it evolved to allow life to arise. We already know a lot about how the Solar System came into being. The Sun and planets formed from a turbulent cloud of dust and gas about 4570 million years ago. The cloud collapsed, and as it flattened to a spinning disk, dust and gas spiralled inwards. The core of the disk became extremely hot, forming the Sun, and the leftover dust and gas formed the planets of our Solar System. Closest to the Sun are the small rocky planets, further away are the outer giant planets of gas and ice, separated by the Asteroid Belt: millions of objects made of rock,metal and organics. Collisions between asteroids cause fragments to be thrown out from the Asteroid Belt; occasionally falling to Earth as meteorites, or causing larger, more devastating impacts. In the outer Solar System, the temperature was sufficiently cold to allow water to solidify to ice. Comets (bodies of ice and dust mixed with organic compounds) are the left-over building blocks of the outer planets. If we know all this about our Solar System, what is there still to learn? We plan to study in detail certain aspects of Solar System history - what was the original dust made from that produced comets? What types of organic compounds were present? How have they been changed by collisions and radiation from the Sun and other stars? How has the ice been altered? We want to know about asteroids - how many small ones are there? what are their shapes, spin rates,and physical structures and how do they evolve?. Answers to these questions will help us understand better the chances of the Earth being hit by one - and maybe help us plan what to do about it. What are asteroids made from? Some asteroids got so hot that they melted and separated into bodies with metal cores and rocky crusts - how do they relate to asteroids that were never molten? Why are some unmelted meteorites rich in metal, whilst others are just rock? All these questions will help us understand the original cloud of gas and dust within which the planets formed, and which also contained the building blocks of life. Could life have got going on any other planets as well as Earth? What about Mars? Its crust was once cut by rivers and glaciers, but is now dry and dusty. The rivers produced minerals that can be seen by from satellites that orbit Mars. We also have rocks from Mars on Earth - chunks broken from the planet by asteroids hitting the surface. We can analyse the constituent minerals and learn about the water that produced some of them. We can also look for signatures of past biological activity has altered the rocks. But how do we start to answer these questions? In our laboratories, we use sensitive equipment to analyse meteorites that have come from the Asteroid Belt and from Mars. We study dust collected from high in the Earth's atmosphere and directly from a comet during a space mission. We do experiments to mimic some of the processes that asteroids and comets have suffered (e.g., being hit in collisions), and we use computers to make models of how asteroids and comets are affected by heat and by the Sun's radiation. We also collect data using instruments mounted on telescopes, and on spacecraft orbiting Mars. We build our own instruments to fly on space missions, and are constantly trying to make them smaller and lighter. We also explore ways in which some of the instruments can be used on Earth, for medical or security purposes. One of the most important benefits of our research is that it helps to train and inspire students to become the next generation of scientists and engineers. We also enjoy telling as many people as possible about the work that we do, and what we have learned from it about our origins.