Cluster Post Launch Support (Apr 2010-Dec2010)

集群启动后支持（2010 年 4 月至 2010 年 12 月）

• 批准号: ST/I001042/1
• 负责人: Andrew Fazakerley
• 金额: $ 27.09万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2010
• 资助国家: 英国
• 起止时间: 2010 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FI001042%2F1
• 关键词: Cluster; Post; Launch; Support; Apr

The Cluster Mission, for the first time, is exploring the magnetosphere with a fleet of four spacecraft orbiting in a group. The magnetosphere is the region of space around the Earth in which the Earth's magnetic field can be detected. It is the operating environment for many spacecraft that affect our quality of life, such as weather, television and communications satellites, as well as scientific spacecraft used to study the Earth, the Sun and solar system, and the cosmos. The magnetosphere is occasionally a dangerous environment for spacecraft, and understanding why this is so is one of the motivations for the Cluster project. The original 2 year mission was extended to allow Cluster to investigate a range of phenomena with different scale sizes, by varying the size of the Cluster tetrahedron from year to year. More recently, the Cluster Multi-Scale Mission has been under way, in which 3 of the spacecraft are separated by ~10,000 km. The distance between one of these and the fourth spacecraft has been varied from a tiny 40 km (in space plasma terms) up to 10,000 km. This work is raising science questions for the future NASA Magnetospheric Multi-scale Mission. Another exciting aspect of the Cluster Multi-scale Mission is that it will visit regions of the magnetosphere which were previously unexplored by Cluster, including the places where the solar wind first meets the magnetosphere, where aurorae are generated and where some magnetospheric substorms originate. In all of these places, Cluster's 4 well instrumented spacecraft, will provide new data to reveal the plasma physical processes at work, which in turn will help us understand how the magnetosphere works. A Plasma Electron And Current Experiment (PEACE) instrument can measure the three dimensional velocity distribution of electrons in a space plasma, for an energy range from a few electronvolts to about 30 kiloelectronvolts, every 4 seconds. A PEACE instrument is flying on each of the four Cluster II spacecraft, and consists of two sensor units and a data processing unit. All 8 sensors and 4 DPUs are still working well, after 8 years in space, despite regular passages through the earth's radiation belts. PEACE can tell us about the density and temperature of the electron plasma near the spacecraft, whether it is flowing and how fast, and whether electron beams from energetic sources elsewhere are passing the spacecraft, guided by the local magnetic field - giving PEACE a remote sensing capability. PEACE can tell us about the electrical currents being carried by the electrons, which is important as such currents transmit forces throughout the magnetosphere. The four PEACE instruments working together can tell us whether there are local flow shears (as in a river where the water flows faster nearer the middle) or even eddies and vortices in the electron plasma; whether there are waves in the plasma or on plasma boundaries, and can determine pressure gradients. This is a unique measurement capability for Cluster, as the counterpart plasma ion instruments do not work on all four spacecraft. It is providing glimpses of the way that explosive energy release processes such a magnetic reconnection work, which is very important as such processes are very active on the Sun and throughout the cosmos. Similarly, PEACE is helping to reveal how collisionless shocks work. Shocks are also phenomena that likely occur throughout the cosmos, and which are capable of energising electrons and ions to very large energies. This grant will allow us to continue operating the PEACE instruments until the end of 2010 and to do essential work on data handling, processing and curation, and maintaining up-to-date instrument calibrations. All this is needed to enable us to make scientifically useful data available to the research community. It will also help us to play our part in constructing and populating the Cluster Active Archive being created by the European Space Agency.

集群任务首次探索磁层，其中一个由四个航天器的机队在一个组中绕。磁层是地球周围空间的区域，可以检测到地球的磁场。许多航天器的操作环境影响了我们的生活质量，例如天气，电视和通信卫星，以及用于研究地球，太阳和太阳系以及宇宙的科学航天器。磁层有时是航天器的危险环境，并且理解为什么这是集群项目的动机之一。最初的2年任务进行了扩展，以允许集群通过改变年度四面体的大小来研究一系列具有不同规模的现象。最近，群集多尺度任务正在进行中，其中3个航天器的分隔约10,000公里。其中之一和第四号航天器之间的距离与最高10,000 km的40 km（在空间等离子方面）之间有所不同。这项工作正在为未来的NASA磁层多尺度任务提出科学问题。集群多尺度任务的另一个令人兴奋的方面是，它将访问磁层的区域，该区域以前未被集群探索，包括太阳风首先遇到磁层的地方，在该磁层中产生了Aurorae，以及某些磁层替代型产生的地方。在所有这些地方，Cluster的4个仪器的太空飞船将提供新的数据以揭示工作中的血浆物理过程，这反过来又有助于我们了解磁层的工作原理。等离子体电子和电流实验（和平）仪器可以测量一个空间等离子体中电子的三维速度分布，其能量范围从几个电子伏尔到约30千明的速度，每4秒钟一次。和平仪器在四个群集II航天器中的每一个上都飞行，并由两个传感器单元和一个数据处理单元组成。尽管经常穿过地球辐射带，但在太空工作了8年后，所有8个传感器和4个DPU仍运行良好。和平可以告诉我们航天器附近电子等离子体的密度和温度，是否流动，速度，以及在其他地方的能量源中的电子束是否经过航天器，在当地磁场的指导下 - 使和平具有遥远的感应能力。和平可以告诉我们电子携带的电流，这很重要，因为这种电流在整个磁层中传递力。共同努力的四种和平仪器可以告诉我们是否有局部流动剪切（如在河流中流动更快的河流），甚至是电子等离子体中的涡流和涡流。等离子体中的波还是等离子边界上是否有波浪，并且可以确定压力梯度。这是群集的独特测量能力，因为对应物等离子仪器在所有四个航天器上都无法使用。它提供了爆炸能量释放过程的方式，这样的磁重新连接工作非常重要，因为这种过程在太阳和整个宇宙中都非常活跃。同样，和平有助于揭示无碰撞冲击的工作方式。冲击也是可能在整个宇宙中发生的现象，并且能够使电子和离子能够为非常大的能量供电。这笔赠款将使我们能够继续运营和平工具，直到2010年底，并在数据处理，处理和策划以及维护最新的仪器校准方面做重要的工作。所有这些都是为了使我们能够为研究界提供科学有用的数据。这也将帮助我们发挥构建和填充欧洲航天局创建的集群活动存档的作用。

项目成果

Cluster observations of a transient signature in the magnetotail: implications for the mode of reconnection

磁尾瞬态特征的聚类观察：对重新连接模式的影响

• DOI: 10.5194/angeo-29-2131-2011
• 发表时间: 2011
• 期刊: Annales Geophysicae
• 影响因子: 1.9
• 作者: Beyene S

Electron acceleration signatures in the magnetotail associated with substorms

• DOI: 10.1029/2009ja014587
• 发表时间: 2010-05
• 期刊: Journal of Geophysical Research
• 作者: Y. Asano;I. Shinohara;A. Retinò;P. Daly;E. Kronberg;T. Takada;R. Nakamura;Y. Khotyaintsev

Global reconnection topology as inferred from plasma observations inside Kelvin-Helmholtz vortices

从开尔文-亥姆霍兹涡旋内的等离子体观测推断出的全局重联拓扑

• DOI: 10.5194/angeo-28-893-2010
• 发表时间: 2010
• 期刊: Annales Geophysicae
• 影响因子: 1.9
• 作者: Bavassano Cattaneo M

Pseudo altitude: A new perspective on the auroral density cavity

伪高度：极光密度腔的新视角

• DOI: 10.1002/jgra.50408
• 发表时间: 2013
• 期刊: Space Physics
• 作者: Alm L

Hot electrons as tracers of large-scale structure of magnetotail current sheets ELECTRONS AS TRACERS OF CS STRUCTURE

热电子作为磁尾电流片大尺度结构的示踪剂 电子作为 CS 结构的示踪剂

• DOI: 10.1029/2011gl047979
• 发表时间: 2011
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Artemyev A