Besides time constraints, Frebel also had to keep an eye on the weather. Even mild cloud cover or slight winds can greatly interfere with nightly measurements, she said.

“We don’t want the stars to twinkle—we want them to stare at us straight without ever winking,” she explained.

Astronomy professor Abraham “Avi” Loeb, who is writing a book about how the first galaxies were created, called Frebel a pioneer, and said he believes this research puts the theory that the galaxy was formed out of small building blocks “on more robust ground.”

Frebel is back in Chile this week continuing the same line of research, hoping to find even more metal-poor stars in dwarf galaxies.

“Now that we’ve smelled blood we want to look out farther and observe fainter stars to test the merging theory in more detail,” she said.

—Staff writer Julie R. Barzilay can be reached at jbarzilay13@college.harvard.edu.