Садржај
Слике
Уплоадјуј своје слике
DSS Images Other Images
Везани чланци
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.
|
Додај нови чланак
Линкови у сродству са темом
Додај нови линк
Чланови следећих група \:
|
Посматрања и Астрометриски подаци
| Сазвежђа: | Тукан |
| Ректацензија: | 23h17m54.48s |
| Deклинација: | -60°59'53.3" |
| Apparent магнитуда: | 8.135 |
| Даљина: | 130.378 parsecs |
| Proper motion RA: | -4.1 |
| Proper motion Dec: | 5.3 |
| B-T magnitude: | 8.536 |
| V-T magnitude: | 8.169 |
Каталог и designations:
|
