sondes

Sondes are instruments designed to measure and transmit information from environments that are not easily accessible. They are used to collect data across science, industry, and medicine, and typically carry sensors, data processing capabilities, and a communications link to a receiver or storage system.

Common types include radiosondes, used in meteorology to measure temperature, humidity, pressure, and wind as they ascend with weather balloons; space probes (sondes spatiales) that explore the solar system or interplanetary space; oceanographic and environmental sondes that record conductivity, temperature, depth, dissolved gases, salinity, and other parameters; medical sondes such as catheters or imaging probes that are inserted into the body to diagnose or monitor conditions; and industrial or laboratory sondes, including pH, temperature, and conductivity probes used in process control and research.

Sondes collect data via sensors, sometimes with data loggers, and transmit it via radio, satellite, or fiber lines; they may be autonomous or tethered, and are often designed to withstand harsh conditions such as high pressure, temperature extremes, or radiation.

The term sonde comes from the French word for probe. In English, the general instrument is often referred to as a probe, while the word sonde is common in meteorology, space exploration, and certain medical and industrial contexts. See also radiosonde, space probe, sensor, and instrument.