Stratified random sampling is a method of sampling that divides a population into smaller groups that form the basis of test samples.

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NASA’s OSIRIS-REx spacecraft will make its first attempt to collect a sample from asteroid Bennu on Oct. 20. Dante Lauretta, OSIRIS-REx principal investigator and a professor of planetary science and ...

NASA's Perseverance Mars rover is preparing to collect its first-ever sample. The agency's Southern California-based Jet Propulsion Laboratory (JPL) said that the rover was searching for a ...

A sample tube on the Martian surface in the shadow of the Perseverance rover. Perseverance is continuing to collect samples as NASA develops a new plan for returning them to Earth. Credit: ...

Understand isokinetic sampling in unidirectional airflow to support accurate particle monitoring and cleanroom compliance.