The first spacecraft to photograph the Moon's far side, Luna 3 launched in 1959 and transmitted 17 low-quality images back to Earth, revealing previously unseen lunar features and marking a significant milestone in lunar exploration.

Launched in 1998, Deep Space 1 tested innovative technologies including an ion engine and autonomous navigation system while successfully flying by asteroid 9969 Braille and Comet Borrelly, capturing the best images of a comet nucleus at that time.

103P/Hartley 2

A small, peanut-shaped comet discovered in 1986 that rotates rapidly and shows unusual activity with dramatic jets of carbon dioxide gas erupting from its surface.