Final answer:
The greatest remaining mysteries in science, particularly astronomy, include whether life exists elsewhere, the nature of the entity at the Milky Way's center, and fundamental questions about the universe's origin and fate.
Step-by-step explanation:
The article refers to the question of whether or not life exists elsewhere as one of the greatest remaining mysteries in science, specifically in the field of astronomy.
This intriguing question, among others such as the nature of the entity at the center of the Milky Way Galaxy pursued by Andrea Ghez and fundamental questions about the beginning and ultimate fate of the universe, represents the epitome of human curiosity and scientific inquiry.
Our pursuit of these questions reflects the passion for understanding our cosmos and a commitment to uncovering its deepest secrets.