Tristan David Weber

Tristan Weber is a graduate student in the department of Astrophysics and Planetary Science at The University of Colorado, Boulder. He currently works with the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission to study how the Martian atmosphere was lost over time, leading to the barren planet we observe today. Using charged particle and magnetic field data from the spacecraft, Tristan analyzes how magnetic fields in the Martian space environment can inhibit or enhance the loss of the planet’s atmosphere. Tristan has taught college courses on astronomy and astrobiology, and intends to continue his teaching pursuits in the future.

Tristan will be defending his thesis in May of 2020, and plans to continue teaching astronomy and physics at a college level. The knowledge and experience gained from the PDP has helped him more clearly decide on teaching as a career, and has given him tools to help him reach and connect with learners of all backgrounds. 


Teaching Activity Summary

Name of Teaching Activity: Introduction to Buoyancy

Teaching Venue: University of Colorado, MASP PEAC program, July 2019

Learners: 42 undergraduate students.

Reflection on teaching and assessing the core science or engineering concept:

Our primary content goal was for students to be able to explain how the density of an object, compared to the fluid it is submerged in, will determine whether or not that object will sink or float. While the basic idea of objects sinking of floating is something that students are introduced to very early in life, there are a large number of misconceptions associated with the topic, including ideas of how shape, orientation, or size might affect an object's buoyancy. We therefore designed this activity as a way for students to develop a first-hand understanding of buoyancy and rewrite any misconceptions they may have, while at the same time applying that knowledge to a natural phenomenon that they chose to investigate.

In our activity, students used a variety of objects and fluids to model their chosen natural phenomenon (which varied in scope from astrophysics to mechanical engineering) in a simplified lab setting. They then used their model to create a poster presentation explaining how density drives the buoyant processes they observed. We evaluated their understanding using a rubric that contained three content dimensions:

(1) Density is an intrinsic property of a substance (solid, liquid, or gas), (2) the total density of a combination of substances is a mixture of their intrinsic densities, and (3) the difference in total density between a substance and the fluid it’s submerged in will determine if it is buoyant.

At the end of the activity, almost all of the learners that I evaluated demonstrated a good level of understanding for content dimensions 1 and 3, but demonstrated little to no evidence of comprehension for dimension 2. Looking back, this may have mostly been due to our choices of target phenomena, as many of them did not strongly incorporate mixtures of substances (or those that did were not primarily focused on those mixtures). If I were to use this activity again in the future, I would either rework content dimension 2 or make sure that all the target phenomena directly relate back to this dimension in addition to the others.