Year 9 & Eratosthenes

Year 9 & Eratosthenes

Throughout November, the Year 9 Science class have been participating in a Big Science trial. This was organised through NetNZ and involved a collaboration between schools, and a science expert, Rodrigo Martinez Gazoni, who is a researcher at the MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Canterbury.

The investigation was repeating the experiments carried out by the Greek mathematician Eratosthenes 2000 years ago.


Eratosthenes Experiment


The activity allowed our students and students at Westland High School in Hokitika to calculate the radius and circumference of Earth via simple experiments that strongly rely on scientific collaboration between distant schools. It also explored various additional phenomena that can be linked to topics in physics, astronomy, geography, history and cultural awareness.

The simple experiments involved measuring the length of the shadow cast by a stick, approximately 1m high, as many times as possible on the hour on consecutive days. This proved to be challenging as even on sunny days the clouds seemed programmed to come and cover the sun at the scheduled measuring times. A series of measurements were made by Rodrigo in Canterbury, students here and Hokitika. The data was put into a spreadsheet, angles of incidence of the sun calculated by trigonometry and scale drawings, and Rodrigo plotted graphs for everyone to see the pattern of sun movement relative to Earth. Using calculated angles of incidence the students were able to calculate the circumference of the Earth to within 75Km of the actual value. This is a 1% error! Rodrigo and the students at both schools were able to communicate via a Padlet inquiry wall and Zoom video conferencing. Our students could see how excited Rodrigo was about the result when he spoke to them.

This was a trial venture and it is hoped that there will be other opportunities to include in the Science curriculum next year.


Click on the image below to view in more detail:
Eratosthenes Poster