impacts

Impact is the effect or influence of one entity on another. Impacts vary by type, magnitude, duration, spatial reach, and whether they are beneficial or harmful, direct or indirect, and intended or unintended.

In physics and engineering, an impact is a collision that transmits forces over a short time, changing momentum and often causing deformation or energy transformation. Impulse, momentum, and energy dissipation describe the process, while material properties and contact duration influence the outcome.

In geology and planetary science, impact events involve objects striking a planet or moon. Meteorite impacts create craters and can eject material, alter landscapes, and influence climate or biology. Evidence includes shocked minerals and elevated siderophile elements in surrounding rocks.

In environmental planning, environmental impact assessment evaluates the likely effects of proposed actions on natural and human systems. It analyzes land use, emissions, biodiversity, and social outcomes, and proposes mitigation, monitoring, and adaptive management.

In economics and social sciences, impacts refer to changes in income, employment, health, education, or equity resulting from policy, technology, or events. Methods include observational studies, experiments where feasible, and causal inference to estimate effect sizes.

Impacts are often uncertain and cumulative, requiring risk assessment, stakeholder input, and transparent communication about benefits and costs to support informed decision-making and resilience.