时间坐标在FITS中的表示
Representations of Time Coordinates in FITS
摘要：
在一系列的三个以前的文件，制定和具体的世界坐标变换的FITS数据表示。第四篇论文涉及编码时间。在天文数据集中已知的所有尺度和精度上的时间都要以明确、完整和自洽的方式描述。采用完善的世界坐标系（WCS）框架，并保持与目前用于指定时间的FITS约定的兼容性，该标准扩展到严格描述时间坐标。世界坐标函数被定义为线性采样的时间轴，并由查找表指定。由此产生的标准与现有的FITS WCS标准一致，并指定了一个元数据集，以实现上述目标。
英文摘要：
In a series of three previous papers, formulation and specifics of the representation of World Coordinate Transformations in FITS data have been presented. This fourth paper deals with encoding time. Time on all scales and precisions known in astronomical datasets is to be described in an unambiguous, complete, and self-consistent manner. Employing the well--established World Coordinate System (WCS) framework, and maintaining compatibility with the FITS conventions that are currently in use to specify time, the standard is extended to describe rigorously the time coordinate. World coordinate functions are defined for temporal axes sampled linearly and as specified by a lookup table. The resulting standard is consistent with the existing FITS WCS standards and specifies a metadata set that achieves the aims enunciated above.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
