Allegheny Observatory Trigonometric Parallax Program

阿勒格尼天文台三角视差计划利用一些最精确的设备来确定距离太阳250秒差距内天体物理上有趣的天体的高精度视差和质量。该程序具有足够的精度，可以获得诸如邻近星团、巨星和变星等光度标准的可靠三角距离；定义之前不在三角函数技术范围内的质量-光度关系的部分；以及探测低质量的附近恒星。恒星视差的测定几乎对天文学的所有领域都具有根本的重要性，因为许多物理参数的测定都需要距离的知识。直到最近，视差测定的局限性一直是存在于大多数天体测量系统中的系统误差，这限制了测定距离的真正准确性。所有迹象表明，阿勒格尼天文台的努力已经成功地纠正了这个问题。盖特伍德博士项目的开发阶段现在已经完成，生产观察正在进行中。

The Allegheny Observatory trigonometric parallax program utilizes some of the most accurate equipment of its kind to determine very high precision parallaxes and masses for astrophysically interesting objects within 250 parsecs of the Sun. The program has sufficient precision to obtain reliable trigonometric distances of such luminosity standards as nearby star clusters, giant stars, and variable stars; to define portions of the mass-luminosity relationship previously outside of the domain of trigonometric techniques; and to detect low mass orbiting nearby stars. The determination of stellar parallaxes is of fundamental importance to almost all areas of astronomy, since the determination of many physical parameters requires knowledge of distance. The limitation in parallax determination up until quite recently has been the presence in most astrometric systems of systematic errors that limit the true accuracy of the determined distances. All indications are that efforts at the Allegheny Observatory have successfully rectified this problem. The development phase of Dr. Gatewood's program is now complete, and production observing is proceeding.