首页     To Survive in the Universe    
Services
    Why to Inhabit     Top Contributors     天文图片     收集     论坛     Blog New!     常见问题     登录  
→ Adopt this star  

HD 191993


目录

图像

上传图像

DSS Images   Other Images


相关文章

The chemical evolution of the solar neighborhood. I - A bias-free reduction technique and data sample
The possible ways of measuring the age-metallicity relation for thegalactic disk in the neighborhood of the sun are discussed. It is shownthat the use of a field star sample chosen on the basis of effectivetemperature introduces a bias which results in a monotonic increase inthe metal abundance of the disk with time. However, if theage-metallicity relation for the disk can be shown to satisfy certaincriteria, the bias introduced in such a sample can be neglected: thegalactic disk apparently satisfies the criteria. It is concluded that asample analyzed through the use of uvby and H(beta) photometry inconjunction with a self-consistent set of theoretical isochronesprovides the least biased, most accurate estimate of the age-metallicityrelation for the disk.

提交文章


相关链接

  • - 没有找到链接 -
提交链接


下列团体成员


观测天体数据

星座:孔雀座
右阿森松:20h17m09.56s
赤纬:-67°27'19.1"
视星:6.724
距离:71.994 天文距离
右阿森松适当运动:39.3
赤纬适当运动:-78.7
B-T magnitude:6.977
V-T magnitude:6.745

目录:
适当名称
HD 1989HD 191993
TYCHO-2 2000TYC 9098-1425-1
USNO-A2.0USNO-A2 0225-30647506
HIPHIP 99994

→ 要求更多目录从vizier