Headshot of David Rice

David R. Rice

Ph.D. Candidate in Astronomy at University of Nevada, Las Vegas
Research on Planet Interiors and Dynamics

I research the formation and evolution of planets from their interiors to their dynamics through computational techniques. My goal as a researcher is to investigate planets through a lens which integrates astrophysics and geoscience.
Read more about my projects below.

Characterizing Planet Interiors

The densities of observed terrestrial planets allow for a range of interior compositions from Mercury-like to volatile-rich. For my dissertation, I test model parameters and quantify systematic uncertainties in inferences of the composition of the Trappist-1 planets. I presented my initial findings at the Exoplanets IV and Rocky Worlds II conferences and a paper is planned for Fall 2022. In addition, I collaborate with high-pressure physicists to test new measurements of planet-building materials: ADS. I'm also open for collaboration with observational groups to characterize their planets. I characterize K2-138's planets in the work below.

Core-Mantle-Water Ternary Diagram showing possible interiors of a planet

MAGRATHEA: Interior Structure Solver

The community uses a variety of models to characterize the interior structure of small planets. Chenliang Huang, Jason Steffen, and I developed MAGRATHEA to be a community standard 1D planet structure code. MAGRATHEA is open-source and can be customized to user-defined planet models. Our code features adaptable phase diagrams for the core, mantle, hydrosphere, and atmosphere and transparent formatting for equations of state. MAGRATHEA's utility is detailed in our publication (ADS) and is archived on NASA's Exoplanet Modeling and Analysis Center.

Use these drop-downs to show a corresponding ternary pre-calculated with MAGRATHEA:
Mass M_Earth Surface Temp. K Atm. Mass %
Core-Mantle-Water Ternary Diagram showing radii of given mass planet

Stable Lifetimes of Planetary Systems

Closely packed planetary systems will experience orbital crossings at a time related to the orbital separations of the planets. After a crossing, the system enters a period of chaotic evolution ending in planetary collisions or ejections. These collisions are essential to the formation of stable systems. I study stability timescales through n-body simulations on Cherry-Creek, UNLV's supercomputer cluster. My first published work, ADS, finds that inclined systems may avoid a planet collision for long periods of time. My second work, ADS, explores the heteroscedasticity of stability time in non-equal mass systems.

Stability time with spacing of systems with different mass planets

Research Group

I research with Prof. Jason H. Steffen. Among other projects, one goal of our group is to track chemical composition of planets from condensation in the protoplanetary disk to engulfment by a white dwarf. We are a part of the Star & Planet Formation group and the Nevada Center for Astrophysics.

Disk Logo

About Me


PDF Link Last updated: 15th Jan. 23

I'm on the job market Fall 2022!

Applying for postdoctoral positions and fellowships

University of Nevada, Las Vegas

Masters in Astronomy.
PhD expected June 2023

Northwestern University

B.A. in Integrated Science, Physics and Astronomy, and Earth and Planetary Science

Presidents Graduate Research Fellow

UNLV Fellowship for '22-23 academic year


I mentor two undergraduates, Tristan Benally and Rosalie Chaleunsouk, in research and received a Mentorship Certificate.

Astronomy on Tap

I am the founder and current emcee of AoT, LV. We present astronomy to our Las Vegas community through engaging and accessible events. We hold 3-4 events a year at Astronomy Aleworks. I maintain an active community on our Facebook.

Public Talks

I love sharing science with others and have given talks through Skype a Scientist and the Las Vegas Astronomical Society. You can watch me discuss Pluto with the CSN Planetarium here.


At UNLV, I taught mechanics, E&M, and modern physics undergraduate labs. In Chicago, I spent a year with SAGA Education providing high-dosage math tutoring to at-risk high school students. Read about the success of the program here.


I tutor all-ages in physics, math, and astronomy. You can hire me for tutoring on Wyzant.

Small Town

Although I love Chicago, Evanston, and Las Vegas, home still means Iowa for me. I grew up in a small suburb of the suburbs of Des Moines.


I enjoy getting out of the city with my wife to explore the outdoors through camping, hiking, and–of course–stargazing.

Get in touch