Intermediate

Equilibrium temperature of an exoplanet

An exoplanet orbits a star of luminosity $L = 0.45\,L_\odot$ at a distance $a = 0.30$ AU. Its Bond albedo is $A = 0.30$ . Assuming rapid rotation and efficient heat redistribution, find its equilibrium temperature. Would liquid water be stable at 1 bar?

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Reading resources

Material that covers the physics behind this problem.

An Introduction to Modern AstrophysicsCarroll & Ostlie
The standard reference for olympiad-level astrophysics. Chapters 1-3 cover the celestial sphere, orbits and the magnitude system.
Textbook
Astronomy NotesNick Strobel
Free, well-illustrated introductory notes covering the whole syllabus at a conceptual level.
Lecture notes
NASA Exoplanet ArchiveNASA / Caltech
Real transit and radial-velocity data. Great source for building your own practice problems.
Website