The scientist most associated with the belief that Earth was at the center of the universe is Claudius Ptolemy. He was a Greco-Roman astronomer, mathematician, and geographer who lived in the 2nd century AD.

His model of the universe, known as the Ptolemaic system, was the prevailing theory for over 1,400 years, until it was replaced by the heliocentric model proposed by Nicolaus Copernicus.

It's important to note that while Ptolemy is most famously associated with this model, he wasn't the first to propose it. The idea of a geocentric universe was popularized by Greek philosophers like Aristotle centuries before Ptolemy. However, Ptolemy's model was the most comprehensive and influential, leading to its widespread acceptance for such a long period.