Research interests

In summary, I use computers to study how planets work.

Overview: Astrobiology and Planetary Science

Astrobiology is the study of the origin, evolution, and distribution of life in the universe. It has been a part of NASA since the 1960’s (then called “exobiology”) and is the driving force behind many space exploration missions, including the Perseverance rover on Mars and the James Webb Space Telescope (JWST). Planets seem to be a favorable environment for life (we live on one), so they are the setting for many astrobiology-related research topics, including those that I am interested in.

Every planet is a complex system. Earth’s behavior is a mosaic of interactions between the atmosphere (air), hydrosphere (water), geosphere (rocks), and biosphere (life). Mars, Venus, Jupiter, and the other planets in and out of our solar system are also complex systems, but with notable differences from Earth. By studying and comparing the fundamental forces operating on different planets, we can provide critical information in the quest to answer astrobiology questions like “How did life originate?”, “How did life evolve to its modern state?”, and “Is there life elsewhere in the universe?”.

Here are some helpful links to learn more about astrobiology:

• NASA Astrobiology
• University of Washington Astrobiology
• National Geographic Astrobiology

My Interests: Planetary Evolution

I am generally interested in how the surface environment, atmosphere, and geochemistry of planets change over time. I typically approach these problems by building theoretical computer simulations and comparing them to data from sources such as planetary rovers, telescopes, or laboratory measurements. Below are a few projects I’ve worked on that are related to this topic.

Ancient Mars

Known life occupies a wide range of environments: from acid mine drainage, to deep sea trenches, to permafrost ice - the one thing that all of these organisms have in common is that they need liquid water to grow, survive, and thrive. Modern Mars does not have abundant liquid water on its surface, but there is convincing evidence that rivers and lakes were present on ancient Mars. Thus, ancient Mars may have been a suitable environment for life, and may have even been inhabited. I study how the surface environment and atmosphere of Mars has changed over time via a variety of processes including atmospheric escape, chemical reactions on the surface, and volcanism. I do this with the goal of reconstructing the conditions on ancient Mars and providing geologic context to evaluate its potential habitability.

Earth’s Neoproterozoic Era

The Neoproterozoic Era on Earth is the time period from 540 million years ago to 1 billion years ago. During this time, Earth went through several dramatic global changes: (1) widespread ice sheets covered the planet in the “Snowball Earth” events, (2) atmospheric oxygen rose by several orders of magnitude, and (3) large, complex organisms appeared in the fossil record for the first time. I study these global changes, try to untangle their relationship, and find their potential causes.

The TRAPPIST-1 Exoplanet System

Exoplanets are planets that orbit stars other than our sun. TRAPPIST-1 is an exoplanet system that consists of an ultracool M dwarf star with 7 transiting, terrestrial planets that are remarkably similar to Earth in mass, radius, and recieved stellar radiation. It is likely that these planets are representative of a larger planet population considering that stars like TRAPPIST-1’s are common in the galaxy. Thus, it is critical to understand the capability of planets orbiting ultracool dwarf stars to sustain secondary atmospheres and host habitable surface conditions when searching for life outside of our solar system. I investigate these topics by observing and characterizing the TRAPPIST-1 planets.