Mechanisms of heat transfer and Newton’s law of cooling are introduced in the first physics and
biophysics courses for a number of university science majors. Several papers have commented on the
derivation of the exponential decay and validity of this law. However, the description of the
phenomena is traditionally described without consideration of basic factors that contribute to the
cooling rate of a body. One of these key factors is the emissivity of the body, which requires
specific instrumentation to be measured. In particular, we present in this paper an experiment to
record the cooling temperatures of an avian egg by means of a thermal camera. The objective is to
comment on the dependence of the cooling process on emissivity, and then propose a methodology for
estimating the emissivity of the cooling object. The method can be applied a priori to other bodies
and is suitable for a biophysics laboratory classroom in higher education.