A Nasa spacecraft set sail for Jupiter and its moon Europa, one of the best bets for finding life beyond Earth.
Europa Clipper will peer beneath the moon’s icy crust where an ocean is thought to slide quite close to the surface. It will not search for life, but rather determine if conditions there can support it. Another mission will be needed to flush out any microorganisms lurking there.
“This is a chance for us to explore not a world that might have been habitable billions of years ago, but a world that might be habitable today — right now,” said program scientist Curt Niebur.
Its enormous solar panels make Clipper the largest craft ever built Nasa to investigate another planet. It will take five and a half years to reach Jupiter and will sneak within 16 miles (25 km) of Europa’s surface – significantly closer than any other spacecraft.
Clipper lifted off from Nasa’s Kennedy Space Center on Monday aboard SpaceX’s Falcon Heavy rocket. Mission cost: $5.2 billion.
One of Jupiter’s 95 known moons, Europa is almost the size of our own moon. It is encased in an ice sheet estimated to be 10 to 15 miles or more (15 to 24 km) thick. Scientists believe this frozen crust hides an ocean that may be 80 miles (120 km) or more deep.
The Hubble Space Telescope observed what appeared to be geysers erupting from the surface. Discovered by Galileo in 1610, Europa is one of the four so-called Galilean moons of Jupiter, along with Ganymede, Io and Callisto.
What kind of life can Europe harbor? Besides water, organic compounds are necessary for life as we know it, plus an energy source. In Europa’s case, it could be thermal vents on the sea floor. Deputy project scientist Bonnie Buratti suggests that any life would be primitive like the bacterial life that arose in Earth’s deep-sea vents.
“We won’t know about this mission because we can’t see that deep,” she said. Unlike missions to Mars where habitability is one of many questions, Clipper’s sole task is to determine whether the moon can support life in its ocean or possibly in any pockets of water in the ice.
When its solar wings and antennae are unfolded, Clipper is about the size of a basketball court — more than 100 feet (30 meters) from end to end — and weighs nearly 13,000 pounds (6,000 kg). The super-large solar panels are necessary because of Jupiter’s distance from the sun.
The main body, about the size of a camper, is packed with nine science instruments, including radar that will penetrate the ice, cameras that will map virtually the entire moon and tools to tease out the contents of Europa’s surface and tenuous atmosphere.
The name hearkens back to the fast sailing ships of centuries past.
The round trip to Jupiter will span 1.8 billion miles (3 billion km). For extra oomph, the spacecraft will swing by Mars early next year and then Earth in late 2026. It will arrive at Jupiter in 2030 and begin science the following year. As it orbits Jupiter, it will cross Europa 49 times.
The mission ends in 2034 with a planned collision with Ganymede – Jupiter’s largest moon.
