CubeSat: Climatology of Anthropogenic and Natural VLF wave Activity in Space (CANVAS)

这一为期4年的项目的目标是发展空间中人为和自然甚低频(VLF)波活动的气候学，该气候学将测量源自闪电和地面发射器并传播到地球磁场(磁层)外部的VLF波能量。以往的研究表明，来自这些源的甚低频波在地球辐射环境的动力学中起着重要的作用。该项目的重点将是量化来自地球表面和大气中的源的甚低频能量有多少通过地球上层大气的带电层传播到磁层。这对于了解地面电磁源对近地空间环境的影响程度很重要。该项目由两名早期职业科学家领导，通过课堂参与吸引研究生，并为本科生和博士后研究经验提供资金。Canvas由部署在1米长碳纤维吊杆末端的三轴磁力搜索线圈和两轴偶极天线组成。这五个波分量加在一起，将用于通过在板载现场可编程门阵列中计算的实时快速傅立叶变换，以1秒的时间分辨率确定波功率谱密度。数据将被发送到地面，以确定全套波参数，包括偏振、平面度和k矢量方向。Canvas CubeSat将使用蓝色峡谷姿态确定和控制系统来提供亚度指向精度，以及之前在CU Boulder成功执行任务的传统航天器子系统。S波段的收发机和双天线将与博尔德的一个新的地面站通信，以下行所有的科学数据。立方体卫星将在近地轨道上进行连续测量，以解决以下科学问题：i)闪电输入空间环境的平均电磁能量是多少？二)在0.3-50千赫的频率范围内，电离层上方的甚低频波能量的频谱是什么？电离层对甚低频能量的传输传递函数是什么？它在空间和时间上是如何变化的？这一裁决反映了美国国家科学基金会的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The goal of this 4-year project is to develop the Climatology of Anthropogenic and Natural Very Low Frequency (VLF) wave Activity in Space (CANVAS) Cubesat which will measure VLF wave energy that originates from lightning and ground-based transmitters and propagates to the outer reaches of Earth's magnetic field (the magnetosphere). Previous research has shown that VLF waves from these sources play a significant role in the dynamics of Earths radiation environment. This project will focus on quantifying how much VLF energy from sources on the Earth's surface and in the atmosphere propagates through the charged layers of Earth's upper atmosphere and into the magnetosphere. This is important for understanding the extent to which ground based electromagnetic sources can impact the near-Earth space environment. The project is led by two early career scientists, engages graduate students through class participation, and provides funding for undergraduate and postdoctoral research experience. CANVAS consists of a three-axis magnetic search coil deployed on the end of a 1-meter carbon fiber boom; together with a two-axis dipole antenna. Together, these five wave components will be used to determine the wave power spectral density at 1 second time resolution using real-time Fast Fourier Transforms calculated in onboard Field Programmable Gate Arrays. Data will be sent to the ground to determine the full set of wave parameters, including polarization, planarity, and k-vector direction. The CANVAS CubeSat will employ the Blue Canyon Attitude Determination and Control System to provide sub-degree pointing accuracy, together with heritage spacecraft subsystems from the previous successful missions at CU Boulder. An S-band transceiver and dual antennas will communicate with a new ground station in Boulder to downlink all of the science data. The cubesat will take continuous measurements in low Earth orbit to address the following science questions: i) What is the average electromagnetic energy input into the space environment by lightning? ii) What is the spectrum of VLF wave energy above the ionosphere in the 0.3-50 kHz frequency range? iii) What is the transmission transfer function of the ionosphere for VLF energy, and how does it vary in space and time?This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.