planetology

Planetology is the scientific study of planets and other bodies that orbit stars, including planets, dwarf planets, moons, and planetary systems. It seeks to understand their origins, structure, composition, dynamics, and evolution through observation, measurement, and modeling. The field covers Solar System objects and exoplanets, as well as the processes that shape their surfaces and atmospheres, such as volcanism, tectonics, erosion, impacts, and atmospheric escape. Planetology integrates concepts from astronomy, geology, geophysics, atmospheric science, chemistry, and biology.

Key subfields include comparative planetology, which contrasts different worlds to infer general principles; planetary geology, focusing on surface processes and internal structure; atmospheric science, studying composition, dynamics, climate, and weather; magnetospheres and interiors, looking at internal heat, differentiation, and magnetic fields; and exoplanet science, exploring planets beyond the Solar System.

Methods combine remote sensing from telescopes with in situ measurements from space missions, sample analysis, laboratory experiments, and computer simulations. Data from orbital spacecraft, landers, and rovers, as well as spectral observations, gravity and topography measurements, support models of formation, evolution, and potential habitability. The field has grown with discoveries of diverse exoplanets and advances in instrumentation, and it often overlaps with astrobiology and planetary science in general.

Historically, the discipline emerged from astronomy and geology, later formalizing as planetary science and planetology in the 20th century. Today, it informs our understanding of planetary systems, world diversity, and the potential for life elsewhere.