Life, Energy, Dynamics and Dark Matter - Exploring X-rays from the Outer Planets

生命、能量、动力学和暗物质 - 探索来自外行星的 X 射线

• 批准号: ST/W003449/1
• 负责人: William Dunn
• 金额: $ 73.04万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FW003449%2F1
• 关键词: Life; Energy; Dynamics; Dark; Matter

The outer solar system is truly a place of wonders: spectacular auroral displays, so energetic that they could power Human civilization; moons with global sub-surface water oceans - potentially perfect environments for life; magnetic bubbles ('magnetospheres') that are the largest coherent structures in the solar system; intense radiation belts filled with particles so energetic that they travel at close to the speed of light; iconic glistening rings extending 20 times the diameter of Earth into space to encircle their gaseous hosts. How the cosmos creates these marvels and what processes govern them is at the heart of solar system science and this research.Historically, NASA and ESA's flagship X-ray observatories, Chandra and XMM-Newton, have been widely used to study the unimaginably energetic or large (black holes, neutron stars or the gas that flows between galaxies). However, X-ray observatories also provide invaluable and under-utilised insights into planetary bodies. My research aims to ensure that we fully utilise the diverse range of X-ray capabilities to study the outer planets.X-rays fluorescence is a process that produces 'fingerprint' signatures of atomic elements. Consequently, it is excellent for determining what atomic elements something is composed of. On Earth, X-ray fluorescence is used for everything from determining whether a piece of art is fake, to identifying lead in paint, chlorine in food and metals in cosmetics. Through the ERF, I will study X-ray fluorescence from Jupiter's moons Io, Europa, Ganymede and Callisto. This will identify which elements are most common on their icy surfaces, distinguishing between different salts in Europa's ocean to identify what conditions are available there for potential life.Europa orbits Jupiter within Jupiter's magnetosphere. This vast magnetic cavity around the planet forms through the combination of Jupiter's rapid-rotation, strong magnetic field, and the constant injections of plasma (ionised particles) from the volcanoes on Jupiter's moon, Io. Plasma makes up 99% of the observed Universe. Understanding what processes govern the behaviours of plasmas is therefore critical to understanding the matter we observe across the cosmos. I will use X-ray observations in tandem with measurements by spacecraft in orbit at the planets to study these fundamental plasma processes in several ways: 1. exploring Jupiter's dancing auroral displays to probe the flows of particles and the processes that control them2. analysing X-ray images of the intense radiation belts to determine how they change over time and what processes trigger these changes3. calculating the X-ray emissions along the boundary between the magnetospheres of Jupiter, Saturn, Uranus and Neptune and the solar wind, laying foundations to take videos of this boundary, to study the global relationship between each planet and its surrounding space envrionment (the solar wind).The study of exoplanets has shown that Ice Giants are amongst the most common type of planet in the Universe. However, our local Ice Giants, Uranus and Neptune, are very poorly understood. The rapid flybys of the Voyager spacecraft in the 1980s are the only visit we have ever made to either planet. Without any near-term plans to visit these planets, we have to study them through telescopes at Earth. I will seek to acquire new X-ray observing time for Uranus. This will enable us to explore many of the exciting hints suggested by previous observations, testing for the presence of: sparkling X-ray aurorae, the X-ray glow of the rings and potential fluorescence from the atmosphere.Through these diverse projects, the research programme will usher in a revolution in the uses of X-ray observations for the outer solar system, founding new research fields and leveraging the X-ray waveband to provide unique insights into the mysterious and wonderous worlds in the outer regions of our solar system.

外太阳系确实是一个充满奇迹的地方：壮观的极光展示，能量如此之大，可以为人类文明提供动力；拥有全球地下水海洋的卫星——潜在的完美生命环境；磁泡（“磁球”）是太阳系中最大的相干结构；充满高能粒子的强辐射带，它们以接近光速的速度传播；标志性的闪亮光环延伸到地球直径的20倍，环绕着它们的气体宿主。宇宙是如何创造这些奇迹的，又是什么过程控制着它们，这是太阳系科学和这项研究的核心。历史上，美国宇航局和欧洲航天局的旗舰x射线天文台钱德拉和xmm -牛顿被广泛用于研究难以想象的能量或大（黑洞、中子星或星系间流动的气体）。然而，x射线天文台也提供了宝贵的和未被充分利用的关于行星体的见解。我的研究旨在确保我们充分利用x射线的各种能力来研究外行星。x射线荧光是一种产生原子元素“指纹”特征的过程。因此，它非常适合用于确定某物由哪些原子元素组成。在地球上，x射线荧光被用于各种用途，从确定一件艺术品是否赝品，到识别油漆中的铅、食品中的氯和化妆品中的金属。通过ERF，我将研究木星卫星木卫一、木卫二、木卫三和木卫四的x射线荧光。这将确定哪些元素在木卫二冰冷的表面上最常见，区分木卫二海洋中的不同盐，从而确定潜在生命存在的条件。木卫二在木星的磁层中绕木星运行。木星的快速旋转、强磁场和木星卫星木卫一上火山不断注入的等离子体（电离粒子）共同作用，形成了环绕木星的巨大磁腔。等离子体构成了99%的可观测宇宙。因此，了解控制等离子体行为的过程对于理解我们在宇宙中观察到的物质至关重要。我将使用x射线观测与行星轨道上的航天器测量相结合，从几个方面研究这些基本的等离子体过程：探索木星飞舞的极光，以探测粒子流及其控制过程。分析强辐射带的x射线图像，以确定它们是如何随时间变化的，以及是什么过程引发了这些变化。计算沿木星、土星、天王星和海王星磁层与太阳风边界的x射线辐射，为拍摄该边界的视频奠定基础，研究每个行星与其周围空间环境（太阳风）之间的全局关系。对系外行星的研究表明，冰巨星是宇宙中最常见的行星类型之一。然而，我们对当地的冰巨星天王星和海王星知之甚少。旅行者号宇宙飞船在20世纪80年代的快速飞越是我们对这两个星球的唯一访问。由于近期没有访问这些行星的计划，我们只能通过地球上的望远镜来研究它们。我将设法获得新的天王星x射线观测时间。这将使我们能够探索许多先前观测中提出的令人兴奋的线索，测试是否存在：闪闪发光的x射线极光、光环的x射线辉光和大气中潜在的荧光。通过这些不同的项目，该研究计划将在使用x射线观测外太阳系方面迎来一场革命，建立新的研究领域，并利用x射线波段为我们太阳系外区域神秘而奇妙的世界提供独特的见解。

项目成果

A Survey of Magnetic Field Line Curvature in Jovian Dawn Magnetodisc

• DOI: 10.1029/2023gl106971
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: W. D. Gu;Z. Yao;Y. Wei;T. Qin;B. Zhang;Y. Xu;W. Dunn;P. Delamere;Y. N. Chen

Exploring Fundamental Particle Acceleration and Loss Processes in Heliophysics through an Orbiting X-ray Instrument in the Jovian System

通过木星系统中的轨道 X 射线仪器探索太阳物理学中的基本粒子加速和损失过程

• DOI: 10.3847/25c2cfeb.e6522cc4
• 发表时间: 2023
• 期刊: Bulletin of the AAS
• 作者: Dunn W

Comparing Jupiter's equatorial X-ray emissions with solar X-ray flux over 19 years of the Chandra mission

钱德拉任务 19 年来木星赤道 X 射线发射与太阳 X 射线通量的比较

• DOI: 10.1002/essoar.10512649.2
• 发表时间: 2022
• 作者: McEntee S

Variation of the Jovian Magnetopause Under Constant Solar Wind Conditions: Significance of Magnetodisc Dynamics

恒定太阳风条件下木星磁层顶的变化：磁盘动力学的意义

• DOI: 10.1029/2023gl104046
• 发表时间: 2023
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Feng E

Handbook of X-ray and Gamma-ray Astrophysics

X射线和伽马射线天体物理学手册

• DOI: 10.1007/978-981-16-4544-0_11-1
• 发表时间: 2022
• 作者: Atkins C