Astronomy at St Andrews 2018-2021

圣安德鲁斯天文学小组对起源的问题很感兴趣：星系、恒星和行星从何而来？它们的形成有哪些基础物理学解释？生命的分布范围有多广，它是如何在地球和其他星球上出现的？我们在解决复杂的数学问题方面处于世界领先地位，我们使用新颖的方法，如高精度的观察和超级计算机的模拟。我们通过苏格兰大学物理联盟（SUPA）和国际上的其他团体加入了苏格兰的行列，寻找地球大小的热行星和冷行星，寻找可能存在生命的宜居世界，并开发探测这些遥远世界上生命的方法。我们的研究跨越了广泛的尺度，从发现几光年外恒星周围的行星系统到测量作用于整个宇宙的引力。我们通过使用机器人广角摄像机来发现“热木星”，这些摄像机监测数千颗恒星，以发现那些在轨道行星从其母恒星前面经过时短暂变暗的恒星。我们使用高精度光谱仪测量这些行星的质量，以测量轨道行星对其主恒星的摆动程度。我们利用机器人望远镜的全球网络来观察引力透镜，从而发现更冷、更小、更像地球的行星，这利用了爱因斯坦的预言，即一颗行星在视线中漂移到一颗遥远的背景恒星时，会使其光线弯曲。我们通过研究积聚形成行星的气体和尘埃颗粒发出的光来了解行星是如何形成的，并与我们的计算机模拟进行比较，以了解可能导致生物分子形成的化学反应。年轻的恒星有很强的磁场，与轨道行星和它们自己的磁场相互作用。我们研究这种相互作用的特征，以了解行星是如何形成和演化的。我们研究低温褐矮星和系外行星大气中的矿物云和闪电的物理性质，这些过程可能在生命起源中发挥作用。我们比较观测结果和计算机模拟来研究恒星是如何在星系中形成的，以及年轻恒星的反馈是如何驱动一种动态的、冒泡的星际介质的，即新恒星诞生的尘埃气体。我们包括大质量恒星死亡时的高能超新星爆炸，以及大质量恒星发出的电离辐射，这些辐射将星系中的气体加热到1万摄氏度以上。在宇宙尺度上，我们测量气体和恒星如何在星系内运动，以研究星系如何形成它们的特征形状，如平盘、旋臂和中心凸起，以及当星系碰撞并合并成更大的椭圆星系时，这些形状是如何变化的。我们研究潜伏在星系核心的超大质量黑洞，了解它们是如何形成和成长的，以及它们巨大的能量和辐射是如何影响宿主星系的演化的。我们研究引力如何在星系内部和更广阔的宇宙中起作用。恒星在星系中的运行速度如此之快，以至于星系的质量似乎太少，无法将星系聚集在一起，而我们膨胀的宇宙似乎正在加速。我们对万有引力的了解足以让我们向其他行星发射太空探测器，但为了理解这些更大规模的谜题，我们研究了暗物质和暗能量的替代概念，将我们的预测与观测结果进行比较，以测试万有引力是如何工作的。因此，我们解决了STFC科学路线图的所有四个挑战：宇宙是如何开始的？它是如何演变的？恒星和行星系统是如何发展的，生命是我们星球独有的吗？宇宙的基本成分和结构是什么？它们是如何相互作用的？我们如何探索和理解宇宙的极端？极端条件下的物理定律是什么？星系、恒星和行星是如何形成和演化的？我们在宇宙中是孤独的吗？

The St Andrews astronomy group is interested in questions of origins: where do galaxies, stars and planets come from, and what fundamental physics explains their formation? How widespread is life and how did it arise on Earth and on other worlds? We are world leaders in solving intricate mathematical problems, and we use novel methods such as observations at very high precision and simulations with super computers. We are joined by other groups across Scotland via the Scottish Universities Physics Alliance (SUPA), and internationally, in searching for hot and cool Earth-sized planets, homing in on habitable worlds where life could exist, and developing ways to detect life on those distant worlds.Our investigations span a wide range of size scales, from discovering planetary systems around stars a few light years away to measuring the force of gravity acting on the whole universe. We discover `hot Jupiters' by using robotic wide-angle cameras that monitor thousands of stars to find those that briefly dim each time an orbiting planet passes in front of its parent star. We measure the masses of these planets using high-precision spectrographs to measure how much the orbiting planet wobbles its host star. We discover cooler and smaller more Earth-like planets by using a global network of robotic telescopes to watch gravitational lenses, exploiting Einstein's prediction that a planet drifting across the sightline to a distant background star bends its light. We learn about how planets form by studying the light from the gas and dust grains that accumulate to form planets, comparing with our computer simulations to understand the chemistry may lead to formation of biological molecules.Young stars have strong magnetic fields that interact with orbiting planets and their own magnetic fields. We study the signatures of this interaction to understand how planets form and evolve. We investigate the physics of mineral clouds and lightning in atmospheres of cool brown dwarf stars and extrasolar planets, processes that may play a role in the origin of life. We compare observations and computer simulations to study how stars form in galaxies and how feedback from young stars drives a dynamic, bubbling interstellar medium, the dusty gas from which new stars are born. We include energetic supernova explosions when massive stars die and the ionising radiation from massive stars that heats the gas in the galaxy to temperatures above than 10,000 degrees Centigrade.On cosmological scales, we measure how gas and stars move within galaxies to study how galaxies form their characteristic shapes of flat discs, spiral arms and central bulges, and how these change as galaxies collide and merge to grow larger elliptical galaxies. We study the supermassive black holes that lurk in galaxy cores, to understand how they form and grow, and how their huge output of energy and radiation affects the host galaxy evolution. We study how gravity works both within galaxies and across the wider universe. Stars orbit in galaxies so fast that there appears to be too little mass to hold galaxies together, and our expanding universe appears to be accelerating. We understand gravity well enough to send space probes to other planets, but to understand these larger scale puzzles we investigate alternatives to current ideas of Dark Matter and Dark Energy, comparing our predictions with observations to test how gravity works.Thus we address all four of the STFC Science Roadmap Challenges: How did the Universe begin and how is it evolving? How do stars and planetary systems develop and is life unique to our planet? What are the fundamental constituents and fabric of the universe and how do they interact? How can we explore and understand the extremes of the universe? What are the laws of physics in extreme conditions? How do galaxies, stars and planets form and evolve? Are we alone in the Universe?