Главная     Выжить во Вселенной    
Services
    Why to Inhabit     Top Contributors     Астрофотография     Коллекция     Форум     Blog New!     Помощь     Войти  
→ Adopt this star  

TYC 652-198-1


Оглавление

Изображения

Загрузить ваше изображение

DSS Images   Other Images


Публикации по объекту

The Hyades: distance, structure, dynamics, and age
{We use absolute trigonometric parallaxes from the Hipparcos Catalogueto determine individual distances to members of the Hyades cluster, fromwhich the 3-dimensional structure of the cluster can be derived.Inertially-referenced proper motions are used to rediscuss distancedeterminations based on convergent-point analyses. A combination ofparallaxes and proper motions from Hipparcos, and radial velocities fromground-based observations, are used to determine the position andvelocity components of candidate members with respect to the clustercentre, providing new information on cluster membership: 13 newcandidate members within 20 pc of the cluster centre have beenidentified. Farther from the cluster centre there is a gradual mergingbetween certain cluster members and field stars, both spatially andkinematically. Within the cluster, the kinematical structure is fullyconsistent with parallel space motion of the component stars with aninternal velocity dispersion of about 0.3 km s(-1) . The spatialstructure and mass segregation are consistent with N-body simulationresults, without the need to invoke expansion, contraction, rotation, orother significant perturbations of the cluster. The quality of theindividual distance determinations permits the cluster zero-age mainsequence to be accurately modelled. The helium abundance for the clusteris determined to be Y =3D 0.26+/-0.02 which, combined with isochronemodelling including convective overshooting, yields a cluster age of625+/-50 Myr. The distance to the observed centre of mass (a conceptmeaningful only in the restricted context of the cluster memberscontained in the Hipparcos Catalogue) is 46.34+/-0.27 pc, correspondingto a distance modulus m-M=3D3.33+/-0.01 mag for the objects within 10 pcof the cluster centre (roughly corresponding to the tidal radius). Thisdistance modulus is close to, but significantly better determined than,that derived from recent high-precision radial velocity studies,somewhat larger than that indicated by recent ground-based trigonometricparallax determinations, and smaller than those found from recentstudies of the cluster convergent point. These discrepancies areinvestigated and explained. } Based on observations made with the ESAHipparcos astrometry satellite. Table~2 is also available in electronicform at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)or via http://cdsweb.u-strasbg.fr/Abstract.html

Добавить новую статью


Внешние ссылки

  • - Внешних ссылок не найдено -
Добавить внешнюю ссылку


Группы:


Наблюдательные данные и астрометрия

Созвездие:Кит
Прямое восхождение:03h17m15.22s
Склонение:+10°08'31.8"
Видимая звёздная величина:9.154
Собственное движение RA:57.6
Собственное движение Dec:3.1
B-T magnitude:9.727
V-T magnitude:9.202

Каталоги и обозначения:
Собственные имена
TYCHO-2 2000TYC 652-198-1
USNO-A2.0USNO-A2 0975-00725777
HIPHIP 15288

→ Запросить дополнительные каталоги и обозначения от VizieR