The launch window for NASA’s Europa Clipper spacecraft kicks off this Monday, marking the start of its nearly six-year, 1.8-billion-mile journey to Jupiter. The mission aims to investigate the frigid moon Europa by looking beneath its icy surface for conditions that might support life.

Why focus on Europa? NASA believes that there is “strong evidence” pointing to an ocean of liquid water hidden beneath its icy crust, which might contain “all the essential elements for life as we understand it.”

The probe’s launch was postponed from its original date of October 10 due to Hurricane Helene. The updated launch window will last until November 6.

The uncrewed Europa Clipper is designed to orbit Jupiter and perform nearly 50 close flybys of Europa, with some approaches occurring as near as 16 miles above the moon’s surface. Instead of searching for life directly, the spacecraft will gather information about the moon’s underwater environment and its potential for sustaining life.

Equipped with a solar panel array as long as a basketball court, the $5 billion Europa Clipper is NASA’s largest spacecraft designed specifically for a planetary mission.

Overview of the Europa Clipper

The spacecraft was initially set to launch atop a SpaceX Falcon Heavy rocket, but the schedule was altered due to Hurricane Milton. Europa Clipper is expected to arrive at Jupiter by April 2030.

Europa Clipper will be accompanied by another probe, the European Space Agency’s Juice mission, which launched on April 14, 2023. Juice is set to arrive at Jupiter in July 2031, just over a year after Europa Clipper.

This mission will also study Jupiter, along with three of its moons: Europa, Ganymede, and Callisto.

Both spacecraft will minimize their time in Jupiter’s intense radiation belts to protect their instruments. NASA has stated that Europa Clipper “will navigate outside of Jupiter’s radiation zones to transmit data, receive new instructions, and prepare for upcoming flybys.”

Where is Europa?

Jupiter is home to 95 officially acknowledged moons, though the actual count is likely higher. Its four largest moons—Ganymede, Callisto, Io, and Europa—are known as the Galilean moons, named after the renowned Italian astronomer Galileo Galilei.

What is Europa like?

Europa has a diameter of approximately 1,940 miles, making it about 10% smaller than Earth’s moon.

This moon is extremely cold, with surface temperatures ranging from minus 210 to minus 370 degrees Fahrenheit, and is covered in ice. The thickness of this ice is estimated to be between 6 and 15 miles.

Scientists believe there is a salty liquid water ocean lying beneath the ice, estimated to be 40 to 100 miles deep.

That’s a substantial amount of water! Even though Europa is only a quarter of the size of Earth, “its ocean may contain twice as much water as Earth’s entire ocean,” according to NASA. “Europa’s ocean is regarded as one of the best locations in our solar system to search for life beyond Earth.”

Despite the frigid temperatures, the water remains liquid due to a process called tidal flexing. This occurs as a result of Jupiter’s gravitational forces, which stretch and compress Europa’s icy shell as it orbits the planet.

Europa completes an orbit around Jupiter every 3.5 days, and the friction from these movements generates enough heat to keep the water in liquid form.

In addition, Europa has a hot core, which might house hydrothermal vents that release heated substances into its oceans.

What will the Europa Clipper investigate?

Europa Clipper will not land on Europa but will utilize its nine scientific tools to examine the moon for what NASA refers to as the three essential elements for life:

• Liquid water: Vital for the growth of organisms, facilitating chemical reactions in living cells, aiding metabolism, and allowing waste removal.
• Chemical elements: This includes carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur.
• Energy: On Europa, energy would come from chemical processes instead of photosynthesis, since sunlight cannot penetrate the ice.

Europa Clipper is part of several missions aimed at studying Europa. Other notable missions include:

• 1973 | Pioneer 10: The first spacecraft to fly past Jupiter, capturing images of Jupiter and its moons, including Europa.
• 1974 | Pioneer 11: Came within 365,000 miles of Europa.
• 1979 | Voyager 1: Took photographs of Europa in March 1979.
• 1979 | Voyager 2: Captured images of Europa in July 1979.
• 1997 | Galileo: Provided data suggesting the presence of a subsurface ocean on Europa.
• 2001 | Cassini: Monitored Europa’s thin atmosphere.
• 2007 | New Horizons: Took images of Europa.
• 2022 | Juno: Flew as close as 220 miles from Europa.