Answer:
A topic or idea or concept that I find most captivating is the study of a stars supernovae. it is captivating to study because of its an area of complexity of how a star collapses within itself it's amazing to watch how a star explodes and how it works together to form clusters or Galaxies or even amazing black holes. it's so amazing how a tiny star forms chains of interstellar galaxies and giant black holes being controlled by dark matter and the law of relativity explained by albeit einstein. it's an intriguing and delicate area of study.
if I wish to learn more i would turn to an astrophysicist for more information.