Planetary Science at the University of Kent

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The Kent group focusses on studies of comets, asteroids, cosmic dust and impact events so we can better understand the origin, evolution and distribution of material throughout the Solar System. We are particularly interested in:-complex organic materials - how they evolved and how they ended up where they are today;- the content and physical properties of comets and asteroids (what they are, how they behave and how they evolved);-how sun light influences the physical properties and dynamics of small bodies such as asteroids;-impact events at all sizes (from small dust impacts to larger impacts which can damage or even break apart bodies made of rock or ice);-finding new ways to collect cosmic dust arriving at the Earth's surface. We will address these areas by: performing experiments in our impact laboratory, studying impact processes through computer models, using data from space missions, telescope observations and modelling, studying materials from space missions and studying samples collected by dust capture instruments we are deploying in remote parts of the world such as the mid-Pacific and the Antarctic.Our experimental work involves creating our own very high speed impacts in the laboratory. We then examine and analyse the impacted materials to see if they have been altered. We aim to determine whether/how the organic and mineral materials that we fire transfer to targets they impact. We also aim to see if the organic materials can be changed during impact events into more complex molecules that are the precursors to life. This will involve studying both the targets and the plumes that rise above the impact point.The targets may also fall apart during impact. We generally know how this works for solid targets. But there are bodies in the Solar System which have ice covered surfaces, over a liquid water sub-surface ocean. We will make such objects in our laboratory and impact them in our gun to see how they break up. To study comets, we will examine dust grains collected in space by NASA from comet 81P/Wild 2. Grain by grain we will work out what the comet is made of and where these materials came from before they formed the comet. We will search here on Earth for cosmic dust from space. It is present in the dust around us, but as it falls from space through the atmosphere, it mixes with our own dust from Earth and mankind's industrial activities, making it hard to identify. By sucking air through filters, and doing this in remote places (mid-Pacific or the Antarctic) with clean atmospheres with little local dust, we will concentrate the amount of cosmic dust we can find. We will then study these samples to learn more about the Solar System bodies that they came from.We will also look at asteroids in space. The YORP effect is a torque experienced by small asteroids, and is caused mainly by thermal photons being emitted from their surfaces after being heated by the Sun. When this happens the asteroid experiences a tiny recoil effect, which can be significant if summed up over the entire surface with countless photons striking it at any given moment. YORP can modify how fast asteroids spin and the orientation of their spin-axis and can take millions of years. This effect is of fundamental importance to Solar System astronomers as it can explain many observed phenomena in asteroidal science. However, despite its importance, there have been only a few cases where the YORP effect has been seen in action, due to the difficulties in measuring the effect. With new telescope data we have obtained we will make significant impact in this field. Our core aim is to achieve additional YORP detections on our sample of small asteroids to further understand this important process. The study will also provide theoreticians with actual measurements to calibrate their calculations