Obliquity Evolution of the Potentially Habitable Exoplanet Kepler-62f.
Astrobiology
; 20(1): 73-90, 2020 01.
Article
en En
| MEDLINE
| ID: mdl-31613645
ABSTRACT
Variations in the axial tilt, or obliquity, of terrestrial planets can affect their climates and therefore their habitability. Kepler-62f is a 1.4 Râ planet orbiting within the habitable zone of its K2 dwarf host star. We perform N-body simulations that monitor the evolution of obliquity of Kepler-62f for 10-million-year timescales to explore the effects on model assumptions, such as the masses of the Kepler-62 planets and the possibility of outer bodies. Significant obliquity variation occurs when the rotational precession frequency overlaps with one or more of the secular orbital frequencies, but most variations are limited to â²10°. Moderate variations (â¼10-20°) can occur over a broader range of initial obliquities when the relative nodal longitude (ΔΩ) overlaps with the frequency and phase of a given secular mode. However, we find that adding outer gas giants on long-period orbits (â¼1000 days) can produce large (â¼60°) variations in obliquity if Kepler-62f has a very rapid (4 h) rotation period. The possibility of giant planets on long-period orbits impacts the climate and habitability of Kepler-62f through variations in the latitudinal surface flux, where large variations can occur on million year timescales.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Planetas
/
Exobiología
/
Medio Ambiente Extraterrestre
Idioma:
En
Revista:
Astrobiology
Asunto de la revista:
BIOLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Georgia