The Long Duartion Exposure Facility (LDEF) was not a typical probe, in that it basically just sat in orbit around the earth with no real interaction from below. It's purpose was to study the effect of long term exposure to space on different materials, to provide badly needed design data about those materials and how they would survive in space.
Related experiments are being carried out on the Mir Space Station with the MEEP experiments.
LDEF provided a wealth of data, which we will put to good use when we start to design our own space craft.