Measuring the Earths Circumference
Location
CoLab, OCB 100
Start Date
27-4-2018 1:30 PM
Document Type
Poster
Description
For my honors contract in the field of Astronomy, I decided to replicate the Greek scholar Eratosthenes, in his observations and experiment that justify that the earth is spherical. The motivation behind this project is to disprove those who deny the value of science and empirical observations. More than 2000 years ago the Greek scholar Eratosthenes reached the conclusion that the earth was a sphere. He did this using the angle derived from the cast shadow length versus the objects height, taken in two cites a known distance apart, and on the same day. I gathered part of my data by utilized a live web cam at the Pier House 60 hotel in Clearwater, FL and took screen shots when the Sun was at its local zenith. Then using Auto Cad, I took measurements of various objects height and shadow lengths. Knowing these two lengths, even using the arbitrary plot system of Auto Cad, with simple trigonometry you can determine the angle of the sun at that time and location. In conjunction to the data collected from the web cam, I also took measurements at Galileo’s Pavilion during Sun’s local zenith the same day. Although the tools at my disposal are much more sophisticated than what Eratosthenes had access to, the application is the same. Accepting that rays of electromagnetic radiation incoming from the sun are parallel. The change in altitude angle of the Sun between two locations, is the angle of the arc distance between the two measurement points.
Image
Measuring the Earths Circumference
CoLab, OCB 100
For my honors contract in the field of Astronomy, I decided to replicate the Greek scholar Eratosthenes, in his observations and experiment that justify that the earth is spherical. The motivation behind this project is to disprove those who deny the value of science and empirical observations. More than 2000 years ago the Greek scholar Eratosthenes reached the conclusion that the earth was a sphere. He did this using the angle derived from the cast shadow length versus the objects height, taken in two cites a known distance apart, and on the same day. I gathered part of my data by utilized a live web cam at the Pier House 60 hotel in Clearwater, FL and took screen shots when the Sun was at its local zenith. Then using Auto Cad, I took measurements of various objects height and shadow lengths. Knowing these two lengths, even using the arbitrary plot system of Auto Cad, with simple trigonometry you can determine the angle of the sun at that time and location. In conjunction to the data collected from the web cam, I also took measurements at Galileo’s Pavilion during Sun’s local zenith the same day. Although the tools at my disposal are much more sophisticated than what Eratosthenes had access to, the application is the same. Accepting that rays of electromagnetic radiation incoming from the sun are parallel. The change in altitude angle of the Sun between two locations, is the angle of the arc distance between the two measurement points.
Comments
The faculty supervisor for this project was William Koch, Astronomy.