Pushing the Boundaries: Solar Physics in an Era of High Spatial and Temporal Resolution

太阳是人类最重要的天体，太阳活动驱动着“太空天气”，对环境和通信有着深远的影响。在地球上，我们可以通过极光等迷人的景象直接看到太阳辐射的影响。然而，目前太阳活动背后的力量无法预测，也无法完全解释。大多数人会认为，当你远离强烈的热源时，比如明火，温度会显著下降。然而，困扰太阳系科学家的最大矛盾之一是，太阳的外层大气比表面热得多！当你离开太阳表面时，温度从6000度左右上升到100多万度，这与常识不符，50多年来一直是太阳系研究的前沿。人们提出了许多理论，试图理解这个复杂动力系统的内部运作，产生了两类不同的理论：耀斑事件和波加热。前者表明，太阳大气中迅速发生的小型爆炸事件可能导致观测到的急剧温度梯度。后者依赖于磁流体动力学（MHD）波的产生，这些波从太阳表面向上传播并在日冕中消散。一个很好的类比是，想象海浪穿过浩瀚的海洋，最终在撞击岩石海岸线时释放出能量。理论认为，如果条件合适，在太阳表面附近通过等离子体的不断搅动产生的MHD波可能向上传播，最终耗散其能量并加热太阳外层大气。作为QUB的STFC博士后，我将利用包含各种高分辨率仪器的现代地面和太空望远镜。我的研究计划的观测部分将侧重于区分各个MHD波，这将使关键特征得以评估。这些包括振荡的模式（纵向的，横向的，等等），速度，方向，当然还有能量。我将把这些数值与大气对太阳加热的数值进行比较，从而使上述理论加热模型得到验证或驳斥。计算机模拟也将用于验证观测方法和准确性，最终形成更为精细的太阳大气模型。随着过去几年太阳物理领域的快速发展（更好的望远镜，探测器和计算机），最终解决大气加热悖论的能力现在已经成为现实，这就是我作为STFC博士后将努力做的事情。

The Sun is the most important astronomical object for humankind, with solar activity driving 'space weather' and having a profound effect on the environment and communications. Here on Earth, we can see directly the effects of the Sun's radiation through fascinating sights such as the aurora. However, currently the power behind the Sun's activity cannot be predicted, or indeed fully explained. Most would expect that as you move away from a fierce heat source, such as a naked flame, the temperature will drop significantly. However, one of the greatest paradoxes plaguing solar-system scientists is the fact that the outer atmosphere of the Sun is much hotter than its surface! An increase in temperature from around 6000 degrees to well over one million degrees as you travel away from the surface belies common sense and has remained at the forefront of solar-system research for over 50 years. Many theories have been proposed in an attempt to understand the inner workings of this complex dynamical system, producing two distinct classes of theory: flare events and wave heating. The former suggests that rapidly occurring, small explosive events in the atmosphere of the Sun may cause the observed steep temperature gradient. The latter relies on the generation of magneto-hydrodynamic (MHD) waves which propagate upwards from the surface of the Sun and dissipate in the corona. A good analogy is to imagine ocean waves travelling across the vast seas before finally releasing their energy when they splash up against a rocky coastline. Theory suggests that MHD waves generated near the surface of the Sun through the continual churning of plasma may propagate upwards if the conditions are correct, ultimately dissipating their energy and heating the outer solar atmosphere. As an STFC Postdoctoral Fellow at QUB, I will utilize modern ground- and space-based telescopes containing a wide assortment of high resolution instruments. The observational component of my research programme will focus on the distinction of individual MHD waves, which will allow key characteristics to be evaluated. These include the mode of oscillation (longitudinal, transverse, etc.), the velocity, the direction and of course, the energy. I will compare these values to those specific for atmospheric heating of the Sun, thus allowing the current theoretical heating models described above to be validated or refuted. Computer simulations will also be implemented to validate observational methodologies and accuracy, culminating in much refined models of the solar atmosphere. With the rapid advancements made in the field of solar physics over the last number of years (better telescopes, detectors and computers), the ability to finally resolve the atmospheric heating paradox is now a reality and that is what I will strive to do as an STFC Postdoctoral Fellow.