A new study shows the Maya Calendar to be much older than previously thought. Slovenian archaeologist Ivan Šprajc played a key role in the groundbreaking study. The new research shows that the Mayan timekeeping system is hundreds of years older than previously indicated, and that it might have been used as far back as 1100 BC. Published in the Science Advances journal, the study used aerial laser scanning of buildings and sites along the south coast of the Gulf of Mexico. Ivan Šprajc is regarded as one of the world's leading researchers in archaeoastronomy.