From the February 2010 issue

When did observers determine that “wandering stars” were not stars at all, but rather planets?

Lyle Schroeder, Milwaukee
By | Published: February 22, 2010
wandering objects
Wandering, planet-sized objects.

When Galileo and others turned early telescopes on these wandering objects starting in 1610, they weren’t sure what they saw. The fixed stars appeared as points of light while the planets were visible as disks.