On Thursday, December 11 we had a number of students from Boston Day & Evening Academy join us for a spectroscopy workshop. The students were partaking in a month-long, intensive unit on the “Birth and Life of a Star.” Extracurricular experiences such as the spectroscopy workshop that we ran for them were essential to their exploration of such a fascinating topic!
We began the workshop by having the students build their own refractive spectrometers to decompose the light from an incandescent bulb into its spectrum. Photon volunteers worked with the students to build a two-lens imaging system, and then they inserted a diffraction grating between the two lenses to convert the imaging system to a spectrometer.
Here, Dan Rybarczyk, a Photon volunteer, works with a Boston Day & Evening student to build a spectrometer.
Next, we took a few minutes to learn about the Bohr Model for hydrogen to explain how a spectrometer can be used to identify the chemical elements. The students were able to engage in active learning as they completed a worksheet on the material by having a discussion with their peers and the Photon volunteers.
One of Photon’s outreach officers, Ryan Gelly, leads a discussion of the assumptions of the Bohr Model.
After this discussion, we used the Bohr Model to predict what hydrogen’s spectral lines would look like. We were then able to verify our predictions experimentally by observing excited atomic hydrogen. Finally, the students went on a scavenger hunt of sorts: each student received an unlabeled element and a diffraction grating. They then mounted the gratings on their smart phones and took pictures of the element while it was being electrically excited. They were then tasked with matching the photos of the spectra that they captured with existing photos of spectra online to determine which element they were observing.
Here is a photo of the excitation spectra of mercury taken during the final part of the workshop.
At the end of the day, both the students and volunteers had a lot of fun learning about the theory and application of spectrometers to astronomy! We hope to see Boston Day & Evening again in the future!