Haven

Haven is the second moon of Cat's Eye, which is a gas giant of 1.3 Jovian masses and the fourth planet in the system of the G2 star, Byers. Radiation from Cat's Eye, not from Byers, makes Haven marginally habitable.

Haven:

is tidally locked but on the Mercurian, not the Lunar, model;

is smaller than Earth with a thinner atmosphere;

has -

great seismic activity because of its proximity to Cat's Eye,
high rocky mountains,
deep valleys,
one almost comfortable valley, Shangri-La, near the equator,
terrestroid biochemistries but dangerous native organisms,
been inhospitable to seeded Terrestrial organisms;

was created by Jerry Pournelle but Poul Anderson wrote one story set there.