Английская Википедия:19 Draconis

Материал из Онлайн справочника
Перейти к навигацииПерейти к поиску

Шаблон:Short description Шаблон:Starbox begin Шаблон:Starbox image Шаблон:Starbox observe Шаблон:Starbox character Шаблон:Starbox astrometry Шаблон:Starbox orbit Шаблон:Starbox detail Шаблон:Starbox catalog Шаблон:Starbox reference Шаблон:Starbox end 19 Draconis, also known as h Draconis, is a star system in the constellation Draco. It is visible to the naked eye as a faint, yellow-white hued star with an apparent visual magnitude of 4.89.[1] Based on its parallax, the system is located about 49.8 light-years (15.26 parsecs) away.[2] It is moving closer to the Earth with a heliocentric radial velocity of −21 km/s.[3]

This is a binary star system with an orbital period of 52.1 days and an eccentricity of 0.22. Only the primary star can be directly detected, via Doppler shifts or perturbations around the system's barycenter. Using spectroscopy and astrometry, the nature of the secondary star can be inferred. The primary star is an F-type main-sequence star with a stellar classification of F8V,[4] 4% more massive than the Sun. Its surface temperature is about 6,298 K, and it emits just over twice the amount of energy that the Sun does. The secondary is only 37% as massive as the Sun, and its luminosity is only 2% that of the Sun. The system is about 4.7 billion years old.[5]

References

Шаблон:Reflist

Notes

Шаблон:Reflist

Шаблон:Stars of Draco

  1. Ошибка цитирования Неверный тег <ref>; для сносок EgUBV не указан текст
  2. Ошибка цитирования Неверный тег <ref>; для сносок HIP не указан текст
  3. Ошибка цитирования Неверный тег <ref>; для сносок Gontcharov2006 не указан текст
  4. Ошибка цитирования Неверный тег <ref>; для сносок Abt не указан текст
  5. Ошибка цитирования Неверный тег <ref>; для сносок Wang не указан текст