When were the rings of Saturn and the moons of Jupiter first seen?
about 200 years ago, in the mid 1800s
about 1,000 years ago, in the late 900s
about 400 years ago, in the early 1600s
about 100 years ago, in the early 1900s
about 200 years ago, in the mid 1800s
about 1,000 years ago, in the late 900s
about 400 years ago, in the early 1600s
about 100 years ago, in the early 1900s