What information about planets can space probes gather that cannot be obtained by telescope?

Space probes can gather detailed data about a planet's surface features, composition, and atmospheric conditions that cannot be obtained by telescopes. Probes can directly analyze samples of soil, rocks, and gases, providing precise measurements of elements and compounds present. Probes can also study magnetic fields, radiation levels, and other environmental factors in close proximity to the planet, offering insights that are not possible from Earth-based observations alone. Additionally, probes can explore regions of a planet that are not visible from Earth, such as the far side of a planet or its moons.