Planetary Science at Kent 2019 - 2022

太阳系引起了许多人的兴趣，但关于它还有许多问题有待回答：它里面有什么？随着时间的推移，这种情况发生了怎样的变化？它是如何演变到现在的状态的？太阳系其他地方现在有生命吗，或者曾经有过生命吗？我们的工作不能指望明确地回答如此重大的问题，但将在提高我们对这些问题的理解方面发挥重要作用。我们广泛研究的一个领域是碰撞--这是一个影响我们太阳系所有天体的主要过程，在它们存在的整个过程中。通过使用我们自己的特殊枪支，我们可以在小范围内重现太阳系中发生的事情。但我们在受控条件下这样做，使用众所周知的起始材料，这样我们就可以深入了解影响过程和这些事件所驱动的变化。我们提议的工作将解决一些问题，比如生命所需的复杂有机分子如何在撞击过程中自然形成于冰冷的物体上。我们还将研究如何很好地测量土卫二自然喷出的水中的物质，这些水是从土卫二南极附近喷出的羽流中产生的。此外，当航天器飞越太阳系天体或收集太空尘埃(来自彗星或小行星)时，在收集样本时会发生高速碰撞。高速撞击会扭曲航天器上的仪器记录的内容，或者极大地改变撞击的粒子。我们的枪在这方面也有帮助--通过在实验室重现这一过程。我们可以计算出当尘埃粒子撞击这些航天器时会发生什么，因此可以从它们产生的撞击特征来解释撞击粒子的细节。这可以用来解释关于它们来自的物体的细节，因为粒子的含量将取决于中形成的条件。例如，一些矿物质只有在液态水存在的情况下才会形成，所以如果它们存在于样本中，这意味着它们来自的身体有一段时间可以获得液态水。我们工作的另一个重点是研究太阳系小天体的内部、表面和大气属性，以帮助了解这些天体是如何形成的，以及自那以来一直在作用于它们的过程，并将继续这样做。我们特别感兴趣的是阳光如何影响小行星的物理性质和动力学。为了帮助这一点，我们将使用雷达。对雷达回波强度的测量可以揭示小行星上的许多特征，这些特征通常只有通过航天器访问才能实现，并可以让我们确定详细的3D形状。然而，对一颗小行星的分析过程非常耗时，可能需要几个月的时间才能完成。我们将开发一种分析小行星雷达回波的新技术，该技术将利用机器学习方法，特别是“神经网络”。我们训练系统为研究人员做出许多决定，目前这对任何3D形状构造都至关重要。我们还将使用这种新技术进行一项雷达观测计划。

The Solar System intrigues many people, but there are many questions that remain to be answered about it: What is in it? How has this changed over time? How did it evolve into its current state? Is there currently, or has there ever been, life elsewhere in the solar system? Our work cannot hope to definitively answer such big questions, but will play an important part in improving our understanding of these issues.One area in which we work extensively is the study of impacts - these are a major process that has affected all of the bodies in our solar system, throughout their existence. By using our own special gun we can recreate on a small scale what goes on in the Solar System. But we do so under controlled conditions, using well known starting materials, so that we can gain insights into the impact process and the changes that these events drive. Our proposed work will tackle issues such as how complex organic molecules needed for life, can form naturally on icy bodies during impacts. We will also look at how well we can measure what is in the water ejected naturally from Enceladus in plumes emerging from near its South pole. Further, when spacecraft fly past Solar System bodies or collect space dust (from comets or asteroids), high speed impacts occur as samples are collected. The high speed impacts can distort what the instruments on spacecraft record, or change the impacting particle quite dramatically. Our gun can also help here too - by reproducing this process in the laboratory. We can work out what happens to dust particles when they impact these spacecraft and therefore make it possible to interpret details of the impacting particle from the impact feature they create. This can then be used to interpret details about the body they came from, since the content of particles will depend on the conditions formed in. For example, some minerals only form in the presence of liquid water, so if they are present in a sample it means that liquid water was available for some time on the body they came from. The other focus of our work is the study of internal, surface and atmospheric properties of Solar System Small Bodies, in order to help understand how these bodies formed and what processes have been acting on them since, and continue to do so today. We are particularly interested in how sunlight influences the physical properties and dynamics of asteroids. To help with this we will use radar. Measurements of the strength of the radar echo can reveal many features on asteroids, which are usually only achieved by a spacecraft visit, and can allow us to determine a detailed 3D shape. However, the analysis process is extremely time-consuming and can take months to complete for a single asteroid. We will develop a new technique for analysing asteroid radar echo's that will utilize machine learning approaches, specifically 'Neural Networks'. We train the system to make many of the decisions for the researcher, currently vital for any 3D shape construction. We will also conduct a programme of radar observations, using this new technique.