Principles of structural geology on rocky planets

The Geology of the Terrestrial Planets

Mapping the Planets—Geology Stakes Its Claim

Planetary geoscience had very little presence in GSA’s first century, but it has a long history in GSA publications. Beginning with the Moon, the transformation of the planets and their satellites from astronomical objects into geological worlds has taken place largely by geologic mapping using telescope and spacecraft imagery and by the application of stratigraphic principles to these new data...

Atmospheric Heat Redistribution and Collapse on Tidally Locked Rocky Planets

Atmospheric collapse is likely to be of fundamental importance to tidally locked rocky exoplanets but remains understudied. Here, general results on the heat transport and stability of tidally locked terrestrial-type atmospheres are reported. First, the problem is modeled with an idealized 3D general circulation model (GCM) with gray gas radiative transfer. It is shown that over a wide range of...

Mineral Radioactivity Promotes Organic Complexity on Rocky Planets

The Role of Irradiation: Irradiation is widely invoked as a mechanism by which simple carbonbearing molecules may be polymerised or otherwise reacted to form progressively more complex molecules that could ultimately synthesize life [1]. In our solar system, cosmic irradiation has been invoked as a source of complex molecules on the Galilean satellites, and on Titan, Pluto, Uranus and Neptune. ...

Most 1.6 Earth-radius Planets Are Not Rocky

The Kepler mission, combined with ground-based radial velocity (RV) follow-up and dynamical analyses of transit timing variations, has revolutionized the observational constraints on sub-Neptune-sized planet compositions. The results of an extensive Kepler follow-up program including multiple Doppler measurements for 22 planet-hosting stars more than doubles the population of sub-Neptune-sized ...