Collaborative Research: CubeSat: Observing Terrestrial Gamma-ray Flash (TGF) Beams With A Pair Of CubeSats

该项目是设计、开发、建造、运行和分析名为“地面射线分析和探测”(TRYAD)的双航天器立方体卫星任务的结果。TRYAD的目的是帮助解开与闪电有关的一种现象的谜团：地面伽马射线，或称TGFs。伽马射线爆发通常发生在遥远的太空中，靠近黑洞和其他高能宇宙现象。20世纪90年代中期，当科学家们发现地球上空发生强烈的伽马射线闪光时，他们感到惊讶。大气中强大的天然粒子加速器参与了闪电的产生，但确切的过程尚不清楚。TGFs是这种粒子加速的结果。TRYAD的具体目标是从其波束内的两个不同的点观察TGFs。所有其他现有的和计划的转化生长因子观测都是单点观测。因此，有了一对立方体卫星，TRYAD将进行独特的、同类中的第一次转化生长因子观测，这对于能够区分几个现有的加速过程模型至关重要，加速过程是闪电的关键部分。通过这种方式，该项目将有助于促进对地球大气中这一有趣而重要的现象的基本理解。除了对照明物理的影响外，TRYAD还将为奥本大学和位于亨茨维尔的阿拉巴马大学的本科生追求广泛的实践学习和培训目标。根据在非盟成功建立的CubeSat计划--奥本大学学生空间计划(AUSSP)--的经验，整个项目的大部分任务将由学生团队在两所大学教授团队的专家监督下执行。此外，该项目将通过两所大学的学分班得到支持。来自非盟和华大以外的学生将有机会通过华大S现有的本科生太阳物理暑期研究经验(REU)项目参与其中。同样，CubeSat和与转化生长因子相关的活动将被纳入非盟一年一度的高中生暑期学院，这是吸引优秀学生加入该计划的有效方式。立方体卫星任务中涉及的新的、基本上未经验证的技术，本质上使该项目与重大风险联系在一起。另一方面，该项目不仅在其自身的研究领域，而且在空间科学和大气研究的更大领域，以及在航空航天工程和教育领域，都具有巨大的变革潜力。TYRAD任务的目的是测量TGFs的波束轮廓和倾斜度，以便区分不同类别的转化生长因子启动模型。这一结果将有助于我们更好地理解转化生长因子粒子加速的物理过程以及雷暴电场。在近地轨道上相距数百公里的一对3U立方体卫星将提供测量结果。TRYAD是一项有重点的任务，通过只携带伽马射线探测器来最大化伽马射线灵敏度。对卫星分离的控制对飞行任务的成功至关重要，这是通过对两颗卫星使用电离层差异阻力来实现的，并通过改变部署的太阳能电池板的方向积极改变。

This project is to design, develop, construct, operate and analyze the results of a dual spacecraft CubeSat mission named "Terrestrial RaYs Analysis and Detection" (TRYAD). The purpose of TRYAD is to help solve the mystery of a phenomenon that's linked with lightning: terrestrial gamma rays, or TGFs. Bursts of gamma rays usually occur far out in space, near black holes and other high-energy cosmic phenomena. Scientists were surprised when, in the mid-1990s, they found strong gamma-ray flashes happening in the skies over Earth. Powerful natural particle accelerators in the atmosphere are involved in creating lightning but the exact process is not yet known. TGFs result from this particle acceleration. The specific objective of TRYAD is to observe TGFs from two separate points within their beams. All other existing and planned TGF observations are single-point. With a pair of CubeSats, therefore, TRYAD will make unique, first-of-its-kind TGF observations that are crucial for being able to distinguish between several existing models for the acceleration process that is a key part of lightning. In this way, the project will help advance the fundamental understanding of this intriguing and important phenomenon in the Earth atmosphere. Beyond its impact on lightening physics, TRYAD will pursue extensive hands-on learning and training objectives for undergraduate students at both Auburn University and University of Alabama in Huntsville. Building on the experiences from the successful, established CubeSat program at AU, the Auburn University Student Space Program (AUSSP), most of the tasks throughout the project will be carried out by student teams under the expert supervision of teams of professors at both institutions. Further, the project will be supported through for-credit classes at both universities. Students from outside AU and UAH will be offered an opportunity to participate via UAH?s existing Heliophysics Summer Research Experience for Undergraduates (REU) program. Likewise, CubeSat and TGF-related activities will be included in the annual Summer Student Institute for High School Students at AU, which is an effective way to attract high-achieving students into the program. The new, largely unproven technology involved in cubesat missions, inherently makes the project associated with significant risks. On the other hand, the project has tremendous potential to be transformational not only within its own research area of lightening physics but also for the larger field of space science and atmospheric research as well as within aerospace engineering and education. The purpose of the TYRAD Mission is to measure the beam profiles and tilts of TGFs in order to distinguish between various classes of TGF initiation models. The results will advance our understanding of the physical process involved in TGF particle acceleration as well as of the thunderstorm electric fields. A pair of 3U CubeSats separated by several hundred km in low Earth orbit will provide the measurements. TRYAD is a focused mission that maximizes the gamma-ray sensitivity by carrying only gamma-ray detectors. Control of the satellite separation is essential to the success of the mission and this is achieved by using ionospheric differential drag on the two satellites, actively changed through modifying the orientation of the deployed solar panels.