ex-nova

例句：

1. 1. The discovery of this new type of star has revolutionized our understanding of the universe.
   这种新星类型的发现已经彻底改变了我们对宇宙的理解。
2. 2. The ex-nova is a rare and fascinating object that scientists are still studying.
   前新星是一种罕见的、令人着迷的天体，科学家们仍在研究它。
3. 3. The study of ex-novas provides important insights into the evolution of stars and galaxies.
   对前新星的研究为我们提供了关于恒星和星系演化的重要见解。