| 翻訳と辞書 |
| Gamma Pegasi ： ウィキペディア英語版 |
Gamma Pegasi
Gamma Pegasi (γ Peg) is a star in the constellation of Pegasus, located at the southwest corner of the asterism known as the Great Square. It also has the traditional name Algenib; confusingly however, this name is also used for Alpha Persei. The average apparent visual magnitude of +2.84〔 puts this at fourth place among the brightest stars in the constellation. The distance to this star has been measured using the parallax technique, yielding a value of roughly with a margin of error of 5%.〔
The asterism of γ Pegasi and α Andromedae, in Hindu astronomy, is called Uttara Bhādrapadā (उत्तरभाद्रपदा) or Uttṛṭṭāti. It is the 26th nakshatra. In Chinese, (), meaning ''Wall (asterism)'' refers to an asterism consisting of γ Pegasi and α Andromedae .〔 p. 170, ''中國星座神話'', written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.〕 Consequently, γ Pegasi itself is known as (, (英語:the First Star of Wall).)〔 (香港太空館 - 研究資源 - 亮星中英對照表 ), Hong Kong Space Museum. Accessed on line November 23, 2010.〕
In 1911, American astronomer Keivin Burns discovered that the radial velocity of this star varied slightly. This was confirmed in 1953 by American astronomer D. Harold McNamara, who identified it as a Beta Cephei variable.〔 (At the time he actually identified it as a Beta Canis Majoris star, which was subsequently designated a Beta Cephei variable.)〔 It has a radial pulsation period of 0.15175 days (3.642 hours), but also shows the behavior of a slowly pulsating B star (SPB) with three additional pulsational frequencies.〔 Its magnitude varies between +2.78 and +2.89 over the course of each pulsation cycle.
This is a large star with almost nine〔 times the mass of the Sun and close to five〔 times the Sun's radius. The stellar classification of B2 IV〔 suggests this is a subgiant star that is exhausting the hydrogen at its core and is in the process of evolving away from the main sequence. It is either rotating very slowly with no measurable rotational velocity or else it is being viewed from nearly pole-on.〔 Gamma Pegasi has a total luminosity of 5,840 times that of the Sun,〔 which is being radiated from its outer atmosphere at an effective temperature of more than 21,000 K.〔 At this temperature, the star glows with a blue-white hue.〔
==References==
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「Gamma Pegasi」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|