Ancient people could tell time by examining the sky. A handheld device called an astrolabe helped. Invented ove
2,000 years ago, astrolabes consisted of two overlapping metal discs. The night sky was drawn on the discs.
People turned the discs until the drawing matched the stars in the sky. Then they'd read markings around the
edge for the time and location. People could track the moon to know when sunrise and sunset would occur.
Astrolabes were?