Key Takeaways:
- Early telescopic observations, beginning around 1610, revealed celestial objects exhibiting planetary motion.
- These objects were distinguished from fixed stars by their appearance as disks, unlike the point-like appearance of stars.
- The observations were made by Galileo and other astronomers utilizing early telescope technology.
- The nature of these "wandering objects" was initially uncertain to early observers.
Wandering, planet-sized objects.
NASA-JPL
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.
