Award Date
12-1-2022
Degree Type
Thesis
Degree Name
Master of Science (MS)
Department
Physics and Astronomy
First Committee Member
Jason Steffen
Second Committee Member
Zhaohuan Zhu
Third Committee Member
Rebecca Martin
Fourth Committee Member
Monika Neda
Abstract
Tidally locked worlds provide a unique opportunity for constraining the climates of detected exoplanets. They are unique in that few exoplanet spin and obliquity states are known or will be determined in the near future. The TRAPPIST-1 exoplanet system has multiple habitable zone planets that, in the past, have been presumed to be tidally locked. However, a recent study shows the dynamical conditions present in the TRAPPIST-1 system make rotation and large librations possible spin states for these planets. I confirm the tendency for these planets to sporadically transition from tidally locked libration to slow rotation using N-body simulations independent from the previous study. I examine the impact of these spin states and use them to best inform energy balance models which predict the temperature profile of the planet’s surface. My findings show that tidally locked planets with sporadic rotation are able to be in both long-term quasi-stable states and chaotic states: where rapid transitions between behaviours are present. Long-term quasistable spin states are likely able to form stable climate systems while the planet exhibits one spin regime behaviour for hundreds of years to hundreds of millennia. 1D EBMs show that tidally locked planets with sporadic rotation around M-dwarfs will experience a relatively small change in substellar temperature due to the lower albedo of ice in an infrared dominant stellar spectrum. The exact effects of large changes in temperature profiles on these planets as they rotate require more robust climate models, like 3D GCMs, to properly examine. However, using comparisons with climate changes on Earth, it is likely that erosion of land masses would increase and major climate systems would experience significant changes.
Controlled Subject
Tidal currents;Planets;
Disciplines
Astrophysics and Astronomy | Physics
File Format
File Size
1148 KB
Degree Grantor
University of Nevada, Las Vegas
Language
English
Repository Citation
Shakespeare, Cody James, "Day ‘N’ Nite: Habitability of Tidally Locked Planets with Sporadic Rotation" (2022). UNLV Theses, Dissertations, Professional Papers, and Capstones. 4618.
http://dx.doi.org/10.34917/35777501
Rights
IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/