penetrometer

A penetrometer is a device to test the strength of a material.

==Soil== There are many types of penetrometer designed to be used on soil. They are usually round or cone shaped. The penetrometer is dropped on the test subject or pressed against it and the depth of the resulting hole is measured. The measurements find whether the soil is strong enough to build a road on. Scientists also use a penetrometer to measure how much moisture is in soil. Penetrometers are used by space probes such as the Cassini–Huygens probe, to measure the amount of moisture in soil on other planets. Penetrometers are furthermore used in glaciology to measure the strength and nature of materials underlying a glacier at its bed.