球面

qiú miàn jǐ hé

球面几何

spherical geometry

qiú miàn zuò biāo

球面坐标

spherical coordinates

qiú miàn shang gòng jiāo diǎn zhī tuǒ yuán shuāng qū xiàn zài qiú xīn tóu yǐng zhōng réng tóu yǐng chéng gòng jiāo tuǒ yuán shuāng qū xiàn

球面上共焦点之椭圆、双曲线，在球心投影中仍投影成共焦椭圆、双曲线。

The cofocal ellipse and hyperbola of spherical surface will also be projected into the cofocal ellipse and hyperbola in gnomonic projection.