Cassini

Huygens descended through the atmosphere of Titan on 14 January 2005 and settled onto its surface — 1.2 billion kilometres from Earth, the farthest any spacecraft has ever landed.

The probe had been carried there by the Cassini orbiter, itself launched on 15 October 1997 aboard a Titan IV(401)B from LC-40 at Cape Canaveral. The combined stack was a joint mission of NASA, ESA, and the Italian Space Agency; no other American rocket then in service could have lifted it.

Huygens transmitted for roughly 90 minutes after touchdown, far longer than the 30 minutes engineers had planned for from the surface.

Cassini remained in Saturn orbit for 13 years, completing 294 circuits before a controlled atmospheric entry on 15 September 2017 — a deliberate end, chosen to protect the moons below. The Titan IV that launched the mission flew a civilian deep-space payload exactly once.