Planetary Science at the University of Kent

肯特小组专注于研究彗星、小行星、宇宙尘埃和撞击事件，以便我们更好地了解整个太阳系物质的起源、演化和分布。我们特别感兴趣的是：-复杂的有机物质-它们是如何进化的，它们是如何发展到今天的；-彗星和小行星的成分和物理性质（它们是什么，它们的行为以及它们是如何演变的）-太阳光如何影响小行星等小天体的物理特性和动力学；-各种规模的撞击事件（小至尘埃撞击，大至可以破坏甚至粉碎由岩石或冰构成的物体）；——寻找收集到达地球表面的宇宙尘埃的新方法。我们将通过以下方式解决这些问题：在我们的撞击实验室进行实验，通过计算机模型研究撞击过程，使用来自太空任务的数据、望远镜观测和建模，研究来自太空任务的材料，以及研究我们在太平洋中部和南极等世界偏远地区部署的尘埃捕获仪器收集的样本。我们的实验工作包括在实验室里制造我们自己的高速撞击。然后，我们检查和分析受影响的材料，看看它们是否被改变了。我们的目标是确定我们发射的有机和矿物材料是否/如何转移到它们影响的目标上。我们还想看看有机物质是否能在撞击事件中转变成更复杂的分子，即生命的前身。这将包括研究目标和在撞击点以上上升的羽流。目标也可能在撞击过程中分崩离析。我们一般都知道这对固体目标是如何起作用的。但太阳系中有一些天体表面被冰覆盖，表面下有液态水海洋。我们将在实验室里制作这样的物体，然后用枪撞击它们，看看它们是如何破裂的。为了研究彗星，我们将检查美国宇航局从81P/Wild 2彗星上收集的尘埃颗粒。我们将一粒一粒地弄清楚彗星是由什么构成的，以及这些物质在形成彗星之前来自哪里。我们将在地球上寻找来自太空的宇宙尘埃。它存在于我们周围的尘埃中，但当它从太空穿过大气层落下时，它与我们自己的地球尘埃和人类工业活动的尘埃混合在一起，使其难以识别。通过过滤器吸入空气，并在偏远的地方（太平洋中部或南极）这样做，那里的大气干净，当地的尘埃很少，我们将集中我们能找到的宇宙尘埃的数量。然后，我们将研究这些样本，以更多地了解它们来自的太阳系天体。我们还将研究太空中的小行星。YORP效应是小行星经历的一种扭矩，主要是由它们表面被太阳加热后发射的热光子引起的。当这种情况发生时，小行星会经历一种微小的反冲效应，如果在任何给定时刻将整个表面的无数光子加在一起，这种反冲效应可能会很显著。YORP可以改变小行星的旋转速度和自转轴的方向，可能需要数百万年的时间。这种效应对太阳系天文学家来说是至关重要的，因为它可以解释许多在小行星科学中观察到的现象。然而，尽管YORP效应很重要，但由于测量效果的困难，只有少数案例看到了YORP效应的作用。利用我们获得的新的望远镜数据，我们将在这个领域产生重大影响。我们的核心目标是在我们的小行星样本上实现额外的YORP探测，以进一步了解这一重要过程。这项研究还将为理论学家提供实际的测量数据来校准他们的计算

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