Tim Hallatt

Astrophysicist

I am an astrophysicist at MIT. I focus on planet formation and the demographics of exoplanets. I am a data-driven theorist, leveraging information encoded in data to understand the underlying physical mechanisms sculpting the observations.

A unifying theme of my science is how extrasolar violence - the grisly processes that destroy planets and protoplanetary disks - contributes to the extraordinary diversity of planetary systems in the Milky Way.

Research

Shedding Light on Desert Dwellers
NEW

Recently discovered 'desert dwellers' defy expectations by managing to survive at extremely close distances from their stars. I show that desert dwellers may be the remnants of giant planets laid bare through tidal destruction. Desert dwellers may therefore provide an unprecedented window into giant planet interiors!

Coupled Planetary Interior and Tidal Evolution
NEW

Planetary tidal evolution is complicated: planet structure dictates how tides operate in the planet, which in turn alter the structure and orbit. I developed a lightweight, accurate method to couple planet structure and dynamics. I used it to constrain the tidal physics operating inside hot, mid-sized planets!

Planet Formation in the Ancient Milky Way

Exoplanet demographics shift between the two dominant stellar populations of the Milky Way. I explore how the formation environment of planets in the Galaxy has differed across cosmic time, and how that may manifest in the planet distribution around some of the oldest stars in the Milky Way. This work has been featured in the press!

Sculpting the sub-Saturn Period Distribution via Atmospheric Evaporation

The exoplanetary orbital period distribution is a fossil record reflecting how planets form and evolve. I demonstrated that mid-sized planets' orbital period distribution can be sculpted by irradiation-driven atmospheric destruction. My theory predicts that such planets become less common around hotter stars, which has since been confirmed!

Explaining the Orbital Period Distribution of Gas Giants

Gas giant planet abundance grows rapidly with orbital period. I showed that this feature can be carved out if giant planets arrive at their final orbital locations via migration through their natal protoplanetary disks. Our theory predicts that the giant planet population grows more massive toward longer orbital periods.

The Galactic Dynamics of Interstellar Interlopers

Interstellar asteroids and comets pass through the solar system as they orbit the Galaxy, allowing us to study extrasolar bodies in exquisite detail. But can we understand where they may originate from, by bridging planetary and Galactic dynamics?

Shedding Light on Desert DwellersNEW