In situ

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "In situ" – news · newspapers · books · scholar · JSTOR (December 2016) (Learn how and when to remove this message)

In situ^[a] is a Latin phrase meaning "in place" or "on site", derived from in ("in") and situ (ablative of situs, "place").^[3] The term refers to the examination or preservation of phenomena within their original place or context. This methodological approach, used across diverse disciplines, maintains contextual integrity essential for accurate analysis. Conversely, ex situ methods examine subjects outside their original context.

The natural sciences frequently implement in situ methodologies. Geological studies employ field analysis of soil composition and rock formations, while environmental science relies on direct ecosystem monitoring to obtain accurate environmental data. Biological field research examines organisms in their natural habitats, revealing behavioral patterns and ecological interactions that laboratory settings cannot replicate. In chemistry and experimental physics, in situ techniques enable the observation of substances and reactions under native conditions, facilitating the documentation of dynamic processes.

In situ applications extend to various applied sciences. Aerospace industry implements on-site inspection protocols and monitoring systems for operational evaluation without system interruption. In medical terminology, particularly oncology, in situ designates early-stage cancers that remain confined to their point of origin. This diagnostic classification—indicating no invasion of adjacent tissues—serves as a crucial determinant for treatment protocols and prognostic assessment. Space exploration utilizes in situ planetary research methods, conducting direct observational studies and data collection on celestial bodies, thereby avoiding the complexities inherent in sample-return missions.

The humanities, notably archaeology, employ in situ methodologies to maintain contextual authenticity. Archaeological investigations preserve the spatial relationships and environmental conditions of artifacts at excavation sites, enabling more precise historical analysis. In art theory and practice, the in situ principle guides both creation and exhibition. Site-specific artworks, such as environmental sculptures or architectural installations, demonstrate deliberate integration with their designated locations. This contextual placement establishes a methodological framework that emphasizes the relationship between artistic works and their environmental or cultural settings.

Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).