Daniel P. Zaleski, Benjamin R. Horrocks, and Nick R. Walker School of Chemistry, Bedson Building, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK. USB Spectrometers and the Temperature of the Sun: Measuring Black Body Radiation in the Palm of Your Hand The 70 th International Symposium on Molecular Spectroscopy, June 25 th, 2015.

Introduction  Historically conceived when scientists tried to answer the question: - What is the spectrum of light when it is in equilibrium with the substance emitting the light?  1900 Max Planck - beginning of quantum theory  Of course, a black body is an idealized physical body that absorbs/emits electromagnetic radiation.  Beauty is: close to reality and simple to calculate -and thus extremely useful  The sun is approximately a black body. Use blackbody radiation to measure the temperature of the sun in this lab.

Setting Up Basic Light Circuit Variable Power Supply (£30 each) Basic Multimeter Some Form of Cover £

Solar Spectrum Atmospheric absorbers Spectrometer doesn’t perform as well away from midband ~1 s acquisition time

Python 2.7

Actual Temperature 5778 K NASA Purposefully doesn’t do sig. figs. for them.

Astrophys. J., 1925, 61, 154.

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Conclusions  Relatively cheap PChem experiment for undergraduates  Introduces blackbody radiation  Light elements of least squares fitting