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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Europa Clipper | 5/6 | https://en.wikipedia.org/wiki/Europa_Clipper | reference | science, encyclopedia | 2026-05-05T13:18:31.671242+00:00 | kb-cron |
=== Launch preparations === Congress had originally mandated the Europa Clipper to launch on NASA's Space Launch System (SLS) super heavy-lift launch vehicle, but NASA had requested that other vehicles be allowed to launch the spacecraft due to a foreseen lack of available SLS vehicles. The United States Congress's 2021 omnibus spending bill directed the NASA Administrator to conduct a full and open competition to select a commercial launch vehicle if the conditions to launch the probe on a SLS rocket cannot be met. On January 25, 2021, NASA's Planetary Missions Program Office formally directed the mission team to "immediately cease efforts to maintain SLS compatibility" and move forward with a commercial launch vehicle. On February 10, 2021, it was announced that the mission would use a 5.5-year trajectory to the Jovian system, with gravity-assist maneuvers involving Mars (March 1, 2025) and Earth (December 3, 2026). Launch was targeted for a 21-day period between October 10 and 30, 2024, giving an arrival date in April 2030, and backup launch dates were identified in 2025 and 2026. The SLS option would have entailed a direct trajectory to Jupiter taking less than three years. One alternative to the direct trajectory was identified as using a commercial rocket, with a longer 6-year cruise time involving gravity assist maneuvers at Venus, Earth and/or Mars. Additionally, a launch on a Delta IV Heavy with a gravity assist at Venus was considered. In July 2021 the decision was announced to launch on a Falcon Heavy rocket, in a fully expendable configuration. Three reasons were given: reasonable launch cost (ca. $178 million), questionable SLS availability, and possible damage to the payload due to strong vibrations caused by the solid boosters attached to the SLS launcher. The move to Falcon Heavy saved an estimated US$2 billion in launch costs alone. NASA was not sure an SLS would be available for the mission since the Artemis program would use SLS rockets extensively, and the SLS's use of solid rocket boosters (SRBs) generates more vibrations in the payload than a launcher that does not use SRBs. The cost to redesign Europa Clipper for the SLS vibratory environment was estimated at US$1 billion.
=== Launch === Europa Clipper was originally scheduled to launch on October 10, 2024, two days after a Falcon 9 launched the ESA's Hera to 65803 Didymos from Cape Canaveral Space Force Station on a similar interplanetary trajectory. However, this launch attempt was scrubbed due to Hurricane Milton making landfall in Florida the previous day, resulting in the launch being finalized for several days later. Europa Clipper was launched on October 14, 2024, at 12:06 p.m. EDT from Launch Complex 39A at NASA's Kennedy Space Center on a Falcon Heavy. The rocket's boosters and first stage were both expended as a result of the spacecraft's mass and trajectory; the boosters were previously flown five times (including on the launch of Psyche for NASA and an X-37B for the United States Space Force), while the center stage was flown for only this mission.
=== Transit and observation === The trajectory of Europa Clipper started with a gravity assist from Mars on March 1, 2025, causing the probe to slow down a little (speed reduced by 2 km/s) and modifying its orbit around the Sun such that it will allow the spacecraft to fly by Earth on December 3, 2026, gaining additional speed. The probe will then arc (reach aphelion) beyond Jupiter's orbit on October 4, 2029 before slowly falling into Jupiter's gravity well and executing its orbital insertion burn in April 2030. After entry into the Jupiter system, Europa Clipper will perform a flyby of Ganymede at an altitude of 500 km (310 mi), which will reduce the spacecraft velocity by ~400 m/s (890 mph). This will be followed by firing the main engine at a distance of 11 RJ (Jovian radii), to provide a further ~840 m/s (1,900 mph) of delta-V, sufficient to insert the spacecraft into a 202-day orbit around Jupiter. Once the spacecraft reaches the apoapsis of that initial orbit, it will perform another engine burn to provide a ~122 m/s (270 mph) periapsis raise maneuver (PRM).
The spacecraft's cruise and science phases will overlap with the ESA's Juice spacecraft, which was launched in April 2023 and will arrive at Jupiter in July 2031. Europa Clipper is due to arrive at Jupiter 15 months prior to Juice, despite launching 18 months later, owing to a more powerful launch vehicle and a faster flight plan with fewer gravity assists.