The solar spectrum at D-building     Where is D-building?     Where is the sun?     Where is Newton's prism?     When shall we see the spectrum?    

The solar spectrum at D building

One day upon the stair,
A solar spectrum sat right there;
It wasn’t there again today;
What day again to see sun's ray?

Introduction

We began with a verse inspired by a poem Antigonish by Hughes Mearns (1899). Our words express the theme of five HTML pages (to be callled chapters) listed above and below.

With the spectrum on the step we stand in comparison, and in contrast, with Newton whose 1666 experiment revealed the solar spectrum with nothing more than a glass prism and a pinhole in the blind. The contrast is that we have simply nothing : merely the material around with accidental relation to our 'experiment'.

Before pressing on with our theme, let's display, as a standby reference, modern technology's High Resolution Solar Spectrum:-

It is from the page at Solar Survey Archive. Hereafter, we shall be reminded of it at the head of each chapter. [Note that the lines were discovered by Wollaston in 1802 and Fraunhofer in 1814.]

My encounter was with a solar spectrum at the East entrance to VU's D-building at the Footscray Park Campus. It led to the present chapters amounting to three chapters of explanation as prelude to the question targeted by the last chapter asking when we shall see the spectrum on the steps. The vehicle of the explanation comprises pages and its underlying source code. Students and lecturers are welcome to profit either from the page, for its explanation, or from the source-code, for its HTML and JavaScript, or from both. [The spectrum above clearly has width greater than height. Note, however, that the spectrum at the east entrance to D-building has width (across a step) less than height (along the step).]

Our investigation involves the inter-relationship among four components: D-building, the Earth, the Sun, and a pane of glass. The pane interupts radiation from the sun to the ground at the point on the earth where D-building sits. We shall divide the work thus into five pages (to be called chapters):-

Natural occurrences of the solar spectrum

The occurrences of the phenomenon:-
[A different kind of phenomenon is that of an aircraft within a circular rainbow from a window of aircraft. A related phenomenon is the view of light patch on ground from aircraft.]