Robotic Explorers of Other Worlds, 1989 to 2016

Launched on May 4, 1989, Magellan used synthetic-aperture radar to map the surface of Venus and measure its gravity. It was the first interplanetary mission launched from the Space Shuttle and the first to test aerobraking to circularize its orbit; contact was lost on October 12, 1994.

Released from Space Shuttle Atlantis on October 18, 1989, Galileo reached Jupiter on December 7, 1995, and became the first spacecraft to orbit an outer planet. It carried an orbiter and an atmospheric entry probe, and it was deliberately destroyed in Jupiter's atmosphere on September 21, 2003.

Launched on December 4, 1996, Mars Pathfinder landed a base station on Mars in 1997. The lander was renamed the Carl Sagan Memorial Station after touchdown, and it was part of NASA's Discovery Program managed by the Jet Propulsion Laboratory.

Sojourner was the 10.6-kilogram rover carried by Pathfinder, and it reached Mars on July 4, 1997. It was the first wheeled vehicle to operate on a body other than Earth or the Moon, working for 92 sols near Ares Vallis before the mission formally ended on March 10, 1998.

Launched on April 7, 2001, 2001 Mars Odyssey carries spectrometers and a thermal imager to look for evidence of water and ice, and it also relays communications for Mars rovers. Still collecting data as of April 2026.

Spirit launched on June 10, 2003, and landed in Gusev crater on January 4, 2004. Planned for about 90 sols, it worked for 2208 sols, over twenty times longer than NASA planners expected, before the mission was called complete.

Opportunity launched on July 7, 2003, and landed in Meridiani Planum on January 25, 2004, three weeks after its twin Spirit. It operated for 5111 sols, about 14 years, until NASA declared the mission complete in 2018.

Launched by the European Space Agency in March 2004, Rosetta rendezvoused with comet 67P/Churyumov-Gerasimenko in 2014 and became the first spacecraft to orbit a comet nucleus. It released the lander Philae and ended its mission with a deliberate hard landing on the comet on September 30, 2016.

Launched in September 2007, Dawn entered orbit around Vesta in July 2011 and around Ceres in March 2015. That made it the first spacecraft to orbit two extraterrestrial bodies and the first to orbit a dwarf planet; the mission ended in November 2018 when its hydrazine ran out.

Launched on August 5, 2011, Juno entered a polar orbit of Jupiter on July 5, 2016, to study the planet. It was originally to be deorbited into Jupiter's atmosphere at the end of its mission, but has been approved to keep orbiting until contact is lost.

Launched on December 3, 2014, the Japanese Hayabusa2 reached the asteroid Ryugu on June 27, 2018. It deployed small rovers and a lander, fired a projectile to expose subsurface material, and returned two samples to Australia in December 2020.

Launched on September 8, 2016, OSIRIS-REx collected a 121.6 gram sample from the asteroid Bennu in October 2020 and returned it to Earth in September 2023. It was the first US spacecraft to return samples from an asteroid, and it was then renamed OSIRIS-APEX for a follow-up visit to Apophis.