An experiment to acquaint the student with a method to measure the distance to the sun by the use of similar triangles .
Light travels in straight lines.
Using a pinhole camera technique, an image of the sun can be formed on a piece of paper. This paper will then be taped to a window through which the sun is shining. An image is formed on a second sheet of paper held at some distance from the hole. Make sure the sheet of paper on which the sun s image is formed is perpendicular to the sun-pinhole line so that the image is circular. The lab recommends drawing circles on the sheet of paper, then moving the paper from the pinhole until the sun s image is the same size as one of the holes.