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Known as one of the foremost scholars of the time, Eratosthenes’ notable achievement was his accurate measurement of the circumference of the earth. He also produced remarkable works in astronomy, mathematics, geography, philosophy, and poetry. Although he made a map of the world, invented a system of longitude and latitude, and with immense accuracy was the first to calculate the tilt of the earth’s axis, using simple geometry and trigonometry, he was able to compute the measurement of the earth by recognising earth as a sphere in space. 

Greek scholars were able to tell that the earth was a sphere by observing ships disappear over the horizon while their masts were still visible, seeing the curved shadow of the earth on the moon during lunar eclipses, and noticing the changing positions of the stars in the sky.

Ground-breaking finding in the history of science

This ground-breaking finding in the history of science through enquiry-based activity, offers students an opportunity and insight into the scientific way of thinking. Earlier this year the UFS partnered in real time with the Ellinogermaniki Agogi School in Greece to replicate an experiment dating back several centuries, using a simple method to calculate the circumference of our planet – which the great Greek mathematician, Eratosthenes, conducted in 240 BC. The Naval Hill Planetarium was the South African (SA) site where the experiment was conducted. Colleagues from Greece joined online, and their SA counterparts were able to watch the Greek version of the experiment on the planetarium dome.

Students used simple materials and ICT tools to collaboratively determine the circumference of the earth using geometrical arguments. The event was flanked by the observation of the sun by means of solar telescopes from both hemispheres. The event, under the framework of the international educational activity, ‘Eratosthenes Experiment’, was organised by Ellinogermaniki Agogi, under the auspices of the Greek Ministry of Education and Religious Affairs. 

Exciting learning experience to learners

Grades 11 and 12 learners from Bloemfontein schools participated in the live online experiment alongside their peers in Greece, who performed the same experiment at the same time. The local schools that participated were Bloemfontein High School, Calculus, Eunice, Fichardt Park High School, Sentraal, Tsoseletso, St Michael’s, President Swart (from Brandfort), and Heatherdale.  

This ground-breaking finding in the history of science through enquiry-based activity, offers students an opportunity and insight into the scientific way of thinking.

The Naval Hill Planetarium and the Science for the Future projects at the UFS collaborated to make the prestigious event possible and thus offer an exciting learning experience to learners interested in science, mathematics, and astronomy.

The international online experiment built on the event that the Boyden Observatory and two observatories in Greece held online on the occasion of the great conjunction of Saturn and Jupiter in December 2020. This year, the event was targeted at schools.