ブラウザの設定でJava Scriptの使用を有効にしてご利用ください。
出典:Wikipedia
出典:『Wikipedia』 (2011/02/20 02:29 UTC 版)
The effective radius (Re) of a galaxy is the radius at which one half of the total light of the system is emitted interior to this radius. This assumes the galaxy is circularly symmetric. This is an important length scale in de Vaucouleurs law which is given as:
Effective radius