| 翻訳と辞書 |
V404 Cygni
V404 Cygni is a binary star system consisting of a black hole with a mass of about and a late G or early K companion star of mass slightly smaller than the Sun in the constellation of Cygnus. The two stars orbit each other every at fairly close range. Due to their proximity the main sequence star would be distorted into egg shape by the black hole's gravity and lose mass to the black hole.
The "V" in the name indicates that it is a variable star, which repeatedly gets brighter and fainter over time. It is also considered a nova, because at least three times in the 20th century it produced a bright outburst of energy. Finally, it is a soft X-ray transient because it periodically emits short bursts of X-rays.
In 2009, the black hole in the V404 Cygni system became the first black hole to have an accurate parallax measurement for its distance from our solar system. Measured by very-long-baseline interferometry using the High Sensitivity Array, the distance is , or light-years.
==Discovery==
On May 22, 1989 the Japanese Ginga Team discovered a new X-ray source that was cataloged as GS 2023+338. This source was subsequently identified as coincident in position with a previously known nova cataloged as V404 Cygni.
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「V404 Cygni」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.
|
|