Imaging is one of the essential techniques to observe astronomical structures. While analyzing the observed images, it is a challenge in many scientific fields to reconstruct the 3‐D structures from 2‐D image(s). This report discusses this challenge in the context of reconstructing the structure of the Earth's magnetosphere from the X‐ray image and presents a new technique. Specifically, it finds the optimum match of tangent directions derived from the X‐ray image and the parameterized magnetopause function. We name this approach as the tangent fitting approach (TFA). TFA is further validated based on the magnetohydrodynamic (MHD) simulations of the X‐ray images with different viewing geometries. TFA enables the reconstruction of the large‐scale magnetopause from a single X‐ray image, applicable to time‐dependent situations such as cases during magnetic storms. It is also noted that TFA has a potential broader application to remote sensing data, for instance, energetic neutral atom (ENA) observations. Lastly, this new approach is compared with other magnetopause reconstruction approaches.

中文翻译：

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使用切线拟合方法从软X射线图像推导出磁饱和度位置

成像是观察天文结构的基本技术之一。在分析观察到的图像时，在许多科学领域中要从2D图像重建3D结构是一个挑战。本报告在从X射线图像重建地球磁层结构的背景下讨论了这一挑战，并提出了一种新技术。特别是，它找到了从X射线图像和参数化的磁更年函数得出的切线方向的最佳匹配。我们将此方法称为切线拟合方法（TFA）。基于具有不同观察几何形状的X射线图像的磁流体动力学（MHD）模拟，可以进一步验证TFA。TFA可以从单个X射线图像重建大规模的磁更年期，适用于与时间有关的情况，例如电磁风暴中的情况。还应注意，TFA在遥感数据（例如高能中性原子（ENA）观测）中具有潜在的广泛应用。最后，将此新方法与其他磁更年期重建方法进行了比较。