Timeline of the Voyager program
NASA's Voyager program, from Grand Tour trajectory studies in 1965 and the two launches in 1977 through the outer-planet encounters, entry into interstellar space, and power-saving measures in 2025.
- Category
- Engineering & Technology
- Events
- 24 events 1965 – 2025
- Generated
- by claude-opus-5-5, as reported by the donor
1965: Flandro publishes outer-planet trajectory studies
Gary Flandro published calculations showing how planetary gravity assists could shorten journeys to the outer planets. His work helped develop the Grand Tour concept, which would exploit a planetary alignment recurring roughly every 175 years.
https://en.wikipedia.org/wiki/Gary_Flandro#The_Grand_Tour_program1972: NASA approves the Mariner Jupiter-Saturn mission
After cancellation of the more ambitious Grand Tour proposal, NASA approved two Mariner-class spacecraft to explore Jupiter and Saturn. JPL managed the mission, which NASA renamed Voyager on March 7, 1977.
https://en.wikipedia.org/wiki/Grand_Tour_program#Mariner_Jupiter-Saturn1977: Golden Records prepared for both spacecraft
A committee chaired by Carl Sagan selected images, music, natural sounds and greetings in 55 languages for gold-plated copper phonograph records carried by both spacecraft. They were intended as messages to extraterrestrials who might encounter the probes.
https://en.wikipedia.org/wiki/Voyager_Golden_Record#Contents1977: Voyager 2 launches from Cape Canaveral
Voyager 2 launched from Cape Canaveral on August 20 aboard a Titan IIIE-Centaur rocket. Its trajectory preserved the option of continuing beyond Saturn to Uranus and Neptune.
https://en.wikipedia.org/wiki/Voyager_2#Launch_and_trajectory1977: Voyager 1 launches on a faster trajectory
Voyager 1 launched on September 5 on a shorter, faster trajectory to Jupiter and Saturn. Despite launching after Voyager 2, it overtook its twin on December 15, 1977.
https://en.wikipedia.org/wiki/Voyager_1#Launch_and_trajectory1979: Voyager 1 finds active volcanoes on Io
Voyager 1 made its closest approach to Jupiter on March 5. Its encounter revealed active volcanism on Io and a thin ring surrounding Jupiter.
https://en.wikipedia.org/wiki/Voyager_1#Flyby_of_Jupiter1979: Voyager 2 flies past Jupiter
Voyager 2 passed Jupiter on July 9, returning detailed views of its moons. Higher-resolution images of Europa revealed intersecting surface markings, evidence of fractures in its icy crust, and relatively few large impact craters.
https://en.wikipedia.org/wiki/Voyager_2#Encounter_with_Jupiter1980: Voyager 1 encounters Saturn and Titan
Voyager 1 passed Saturn on November 12 after encountering Titan, Saturn's largest moon. Its measurements revealed a dense atmosphere composed mainly of nitrogen, while haze obscured Titan's surface.
https://en.wikipedia.org/wiki/Voyager_1#Flyby_of_Saturn1981: Voyager 2 flies past Saturn toward Uranus
Voyager 2 made its closest approach to Saturn on August 26 UTC, studying the planet and its moons before continuing toward Uranus. A scan-platform malfunction during the encounter required engineering investigation.
https://en.wikipedia.org/wiki/Voyager_2#Encounter_with_Saturn1986: Voyager 2 makes the first flyby of Uranus
Voyager 2 became the first spacecraft to fly past Uranus on January 24. It returned detailed observations of the planet, its moons, rings and magnetic field.
https://en.wikipedia.org/wiki/Exploration_of_Uranus#Voyager_21989: Voyager 2 makes the first flyby of Neptune
Voyager 2 became the first spacecraft to fly past Neptune on August 25. After completing its final planetary encounter, it headed below the plane of the planets on a course toward interstellar space.
https://en.wikipedia.org/wiki/Voyager_2#Encounter_with_Neptune1990: Voyager Interstellar Mission begins
Following the final planetary encounter in 1989, the Voyager Interstellar Mission officially began on January 1. Its goals included studying the outer heliosphere, locating its boundary with interstellar space, and exploring the interstellar environment.
https://en.wikipedia.org/wiki/Voyager_program#Voyager_Interstellar_Mission1990: Voyager 1 photographs the Pale Blue Dot
On February 14, Voyager 1 photographed Earth as part of a Solar System family portrait proposed by Carl Sagan. The spacecraft was about 6 billion kilometers from the Sun. Its cameras were powered off later that day to conserve energy.
https://en.wikipedia.org/wiki/Pale_Blue_Dot1998: Voyager 1 becomes the most distant human-made object
On February 17, Voyager 1 surpassed Pioneer 10's distance from the Sun and became the most distant human-made object. Voyager 1 was then about 69.4 astronomical units from the Sun.
https://en.wikipedia.org/wiki/Voyager_1#Exit_from_the_heliosphere2004: Voyager 1 crosses the termination shock
In December, Voyager 1 crossed the termination shock about 94 astronomical units from the Sun. There the solar wind abruptly slows, marking entry into the heliosheath, the outer region of the heliosphere.
https://en.wikipedia.org/wiki/Heliosphere#Termination_shock2007: Voyager 2 crosses the termination shock
Beginning around August 30, Voyager 2 crossed the termination shock several times at about 84 astronomical units from the Sun. Its crossing closer to the Sun than Voyager 1's revealed an asymmetric boundary, potentially influenced by interstellar magnetic pressure and changing solar-wind conditions.
https://en.wikipedia.org/wiki/Voyager_2#Interstellar_mission2012: Voyager 1 enters interstellar space
Voyager 1 crossed the heliopause on August 25 at about 122 astronomical units from the Sun. Plasma-wave measurements obtained the following year helped establish that it had entered the denser interstellar plasma beyond the heliosphere.
https://en.wikipedia.org/wiki/Voyager_1#Interstellar_medium2017 – 2018: Voyager 1 tests thrusters dormant for 37 years
On November 28, engineers successfully tested Voyager 1's trajectory-correction thrusters after 37 years without use. In January 2018, the spacecraft switched to these thrusters to maintain its antenna's orientation toward Earth as its attitude-control thrusters degraded.
https://en.wikipedia.org/wiki/Voyager_1#Concerns_with_the_orientation_thrusters2018: Voyager 2 crosses the heliopause
Voyager 2 crossed the heliopause on November 5 at about 119 astronomical units from the Sun, following Voyager 1 into interstellar space. Its working plasma science instrument provided direct measurements of the transition.
https://en.wikipedia.org/wiki/Voyager_2#Interstellar_mission2020: Antenna upgrade interrupts commands to Voyager 2
In March, Australia's Deep Space Station 43 went offline for upgrades, interrupting routine commands to Voyager 2 while reception of its data continued. Test commands succeeded on October 29, and the approximately 11-month upgrade was completed in early 2021.
https://en.wikipedia.org/wiki/Voyager_2#Interstellar_mission2022: Edward Stone retires as project scientist
NASA announced Edward Stone's retirement after 50 years as Voyager project scientist, naming Linda Spilker as his successor. Stone had led the mission's science since 1972, through the planetary encounters and both spacecraft's entry into interstellar space.
https://en.wikipedia.org/wiki/Edward_C._Stone#Voyager_program2023: Mispointed antenna briefly cuts contact with Voyager 2
Commands sent on July 21 inadvertently pointed Voyager 2's antenna 2 degrees away from Earth, interrupting communication. Controllers sent a powerful signal from Canberra to reorient the spacecraft, and science and telemetry data resumed on August 4.
https://en.wikipedia.org/wiki/Voyager_2#Interstellar_mission2023 – 2024: Engineers work around Voyager 1's memory failure
Voyager 1 stopped sending readable data on November 14, 2023, after part of its flight data subsystem memory failed. Relocating affected software restored engineering data on April 20, 2024; all four operating science instruments were returning usable data by June 13.
https://en.wikipedia.org/wiki/Voyager_1#Communication_issues2025: NASA shuts down instruments to extend Voyager missions
To conserve declining electrical power, mission controllers turned off Voyager 1's cosmic ray subsystem on February 25 and Voyager 2's low-energy charged particle instrument on March 24. These shutdowns helped extend both spacecraft's science operations.
https://en.wikipedia.org/wiki/Voyager_2#Power