The problem was, he didn't just support Copernicus's idea, and he did not stick to teaching it as a theory, as the church allowed him to do. His problem was that he promoted it aggressively as the absolute truth, and that is what put him on a collision course with the Vatican. He was tried for heresy because he was held to be trying to reinterpret The Bible.
Copernicus's theory, as promoted by Galileo, was eventually replaced by Kepler's theory, but the idea of having the Sun at the center was retained. In the 18th century the discovery of the law of gravity and the laws of motion showed that Kepler's model was very close to reality, and it's the model in use today with slight modifications from relativity.
Nicolaus Copernicus proposed the heliocentric model in the 16th century, stating that the Earth revolves around the Sun. Galileo Galilei supported this idea in the 17th century through his observations with telescopes.
Galileo observed using a telescope that the moon had mountains and craters, Jupiter had moons orbiting it, Venus exhibits phases like our moon, and Saturn had "ears" or rings. These observations supported the heliocentric model proposed by Copernicus.
Galileo Galilei was forced to admit publicly by the Catholic Church that the Earth stood motionless at the center of the universe in 1633. This was part of the Inquisition's trial against him for supporting the heliocentric model proposed by Copernicus.
Galileo disproved the notion that the Earth was the center of the universe by observing the phases of Venus through a telescope, which supported the heliocentric model proposed by Copernicus. This provided evidence that Earth and other planets revolve around the sun, not Earth being the center of the universe.
Nicolaus Copernicus and Galileo Galilei challenged the idea of the Earth-centered universe with the heliocentric model, which placed the Sun at the center of the solar system. Copernicus introduced this concept in the 16th century, while Galileo's observations through a telescope provided evidence for the heliocentric model in the 17th century.
Galileo
Galileo Galilei
The two main proponents in the early days were Nicolas Copernicus and Galileo.
Copernicus proposed the theory of a heliocentric model while Galileo improved the telescope, studied Jupiter's moons, and supported the heliocentric model
Galileo Galilee
Ptolemy proposed a geocentric model, with Earth at the center and planets orbiting it. Copernicus suggested a heliocentric model, with the Sun at the center of the solar system. Galileo's telescopic observations supported the heliocentric model and provided evidence for Copernicus' theory.
Scientists such as Nicolaus Copernicus and Galileo Galilei developed ideas that contradicted Ptolemy's geocentric model of the universe. Copernicus proposed a heliocentric model with the sun at the center, while Galileo's observations through a telescope supported this idea, leading to the eventual acceptance of the heliocentric model.
Nicolaus Copernicus was the first to propose a heliocentric model of the solar system in the 16th century, which placed the Sun at the center with planets orbiting around it. Galileo Galilei supported Copernicus's ideas and used his observations through a telescope to provide further evidence for this model in the early 17th century.
Both scientrusts challenged ideas supported by roman Catholic church
Galileo was born 19 years after Copernicus died.
Galileo Galilei . He only helped support the theory through his observations , he didn't invent the model, Copernicus did.
Copernicus (16C); supported later by Galileo using observations aided by the newly-developed telescope.