'Alien hunting mission': The timeline of NASA's 6-year journey to Jupiter's icy moon with Europa Clipper

On October 14, NASA's Europa Clipper spacecraft embarked on a groundbreaking mission to explore the potential habitability of Europa, one of Jupiter's icy ocean moons. Although not directly tasked with "alien hunting," this mission is pivotal for advancing our understanding of life beyond Earth. Europa is believed to possess essential elements for life beneath its thick icy crust, including water and complex chemicals. By investigating these conditions, the Europa Clipper aims to refine our approach for future missions that might directly search for extraterrestrial life.

According to NASA, the mission's primary scientific goals are to understand the ice shell's nature and the ocean beneath, as well as to examine Europa's composition and geology. "The detailed exploration of Europa will help scientists better understand the astrobiological potential for habitable worlds beyond our planet," the agency stated on its Europa Clipper Mission website.

However, reaching the Jovian system is no small feat. Jupiter is located an average of 444 million miles (778 million kilometers) from Earth, and the $6 billion spacecraft will not follow a direct route. Instead, it will undertake a grand tour of the solar system, involving several flybys of other planets. 

The Europa Clipper is scheduled to make its first significant maneuver with a flyby of Mars on March 1, 2025, coming within 300 to 600 miles (482 to 965 kilometers) of the Martian surface. This encounter will not send the spacecraft directly to Jupiter; instead, it will loop back toward Earth.

The spacecraft will return to our planet for a brief flyby on December 3, 2026, coming as close as 2,000 miles (3,200 kilometers) before departing for its final destination. The journey to Jupiter will take approximately six years, with the Europa Clipper expected to arrive in the Jovian system in April 2030, covering at least 1.8 billion miles (2.9 billion kilometres) in the process.

Upon reaching Jupiter, the spacecraft will fire its engines to slow down and begin a series of flybys of the gas giant and its moons. It will first encounter Ganymede, the largest moon in the solar system, before finally reaching Europa in spring 2031. The mission will commence its scientific campaign in May 2031, during which the Europa Clipper will conduct 49 flybys of the moon, utilizing nine scientific instruments to gather crucial data on its icy surface and underlying ocean.

Europa is a prime candidate for habitability studies due to its subsurface ocean, estimated to be about 62 miles (100 kilometers) deep—much deeper than Earth's oceans. This ocean is thought to be in contact with a rocky seafloor, potentially allowing for hydrothermal activity that could support life.

The gravitational influence of Jupiter creates powerful tidal forces on Europa, which generate heat and may provide the necessary energy for microbial life beneath the icy shell. Researchers also theorize that organic molecules needed for life were likely delivered to Europa by asteroids and comets, further increasing its potential as a habitat.

As the Europa Clipper approaches its mission's conclusion in September 2034, it will be deorbited and sent crashing into Ganymede's surface. The data collected over nearly a decade could bring humanity closer than ever to answering the profound question of whether life exists beyond our planet.