Galileo improved upon the rudimentary telescopes of his day, creating instruments which allowed him to see the objects of outer space with greater clarity than anyone before him. He made careful observations and drew meticulous sketches to document what he saw. Despite the fact that he was labeled a heretic for believing that his observations show the earth is not the center of the universe, and despite the fact that his works were not fully released from the Catholic Church’s ban until 1835, his amazing words and illustrations survived. Here are a few examples of his accomplishments…
Observations of the Moon
In Galileo’s time it was believed that the heavenly bodies were all perfectly created spheres, that could not have their own orbiting moons, or any mountains, craters, or other features that would mar their perfection. When Galileo looked at the moon through his telescope he was able to see that the moon clearly has many mountains and craters and was definitely not a perfectly smooth sphere. He made detailed sketches of what he saw, part of the evidence that led him to believe that the other planets are not perfect spheres orbiting the earth as others believed in his day.
Sketches of the Phases of Venus
Galileo observed that the planet Venus goes through phases over time, just like the moon. This would only happen if the planets orbited the sun, and not the earth. These observations provided strong evidence that the geocentric model of the solar system was not correct. Despite this and other evidence, Galileo’s belief in the heliocentric model still ended up being labeled as heretical.
Sketches of Sun Spots
Galileo created meticulous drawings of the movement of sunspots over time, showing how they traveled across the face of the sun and would seem to appear and disappear. Others had argued that sunspots were simply the planet Mercury crossing in front of the sun, or bodies orbiting the sun. Galileo argued that sunspots were more like clouds on the surface of the sun, something which contradicted the prevailing view of the perfect and unchanging heavenly bodies.
Observations of the Moons of Jupiter
When Galileo looked at Jupiter through his telescope, he observed small points of light around it that he first thought were stars. He noticed however, that the lights appeared at different positions through time. Galileo created simple sketches representing Jupiter with a circle, and the lights as asterisks. He showed that the lights must be moons orbiting Jupiter, something that many were unwilling to believe, because it was thought that only the earth could have orbiting bodies.
Sketches of the Pleiades Constellation
Galileo studied the stars and the Milky Way and the constellations that were known in his time. He found that there were many more stars visible with a telescope than could be seen with the naked eye. Galileo was seeing stars that no one had seen before, and he recorded his observations with beautiful sketches.
Galileo’s works would eventually help to change our views on the nature of the universe and our place within it. Thankfully, despite the censorship imposed on his ideas, his works are still here for us to enjoy and learn from today.
Check out this t-shirt design we created featuring a quote from Galileo! Available here!