Cold Cases: Solving the Mystery of Wide-Orbit Planets with TESS

  • CART Astrophysics Seminar Series

November 20, 2025 2:00 PM
PAIS 3205

Host:
Diana Dragomir
Presenter:
Mallory Harris (UNM)
Mapping exoplanet demographics across orbital distances requires pushing beyond the short-period planets that dominate current catalogs, especially for M dwarf stars. While the Kepler mission successfully characterized inner systems, cold planets remain elusive due to low transit probabilities and long orbital periods. Yet, understanding outer system structures is crucial for constraining planet formation and evolution models. The upcoming Nancy Grace Roman Space Telescope will revolutionize this space by detecting wide-orbit planets through microlensing, but TESS offers the opportunity to begin bridging the gap between close and wide-orbiting planets today. In this talk, I will present on the current status of my TESS transit detection pipeline, which is capable of finding both single-transit events and compact multiplanet systems. Recent upgrades—including Bayesian transit fitting with PyMC and validation on known events—enable more robust inference for planets beyond the typical TESS period range and lay the groundwork for occurrence rate studies of cold planets around low-mass stars. I will also discuss my work on TESS’s first potential microlensing planet candidate—a separate effort that demonstrates TESS’s ability to probe wide-orbit planets as a byproduct of its mission. Together, these projects highlight how TESS can help extend our view from compact inner systems toward the cold, distant planets that shape planetary architectures.

Upcoming Events

Search for Neutrinoless Double Beta Decay with LEGEND Using Simulation and Machine Learning
Zafer Acar (UNM)
Nuclear, Particle, Astroparticle and Cosmology (NUPAC) Seminars
May. 5, 2:00 PM
PAIS 3205

TBD
Sam Halverson (JPL)
CART Astrophysics Seminar Series
May. 7, 2:00 PM - May. 7, 3:00 PM
PAIS 3205

Title TBD
Presenter TBD
Physics and Astronomy Colloquium
May. 8, 3:30 PM - May. 8, 4:30 PM
PAIS 1100

Finals Week -- No Colloquium

Physics and Astronomy Colloquium
May. 15, 3:30 PM - May. 15, 4:30 PM
PAIS 1100

Department Convocation
Kathrin Spendier, PhD
Special Talk
May. 16, 12:00 PM - May. 16, 2:00 PM
PAIS 1100 and Lobby