Jan Heweliusz

Jan Heweliusz was a Polish astronomer and instrument maker who lived in the 17th century. He is best known for inventing the first practical telescope and making significant contributions to the field of astronomy. Heweliusz was also a skilled instrument maker and created several innovative instruments, including the sextant, which is named after him. He was a pioneer in the field of astronomy and paved the way for future generations of astronomers.