NASA’s Europa Clipper launched on mission to icy Jupiter moon

By Joel Achenbach / The Washington Post /

CAPE CANAVERAL, Fla. — NASA’s Europa Clipper, the largest robotic probe the agency has ever built, rocketed into space Monday on a mission to scrutinize one of the most intriguing worlds in our solar system, the ice-encrusted moon of Jupiter that scientists suspect has a deep subsurface ocean.

The journey to Europa will take 5½ years and cover 1.8 billion miles, including a gravity boost from Mars early next year that will send it back toward Earth for a second boost that slings it out to Jupiter.

The spacecraft launched on top of a SpaceX Falcon Heavy rocket precisely six minutes after noon Eastern time under blue skies. The roar of the Falcon Heavy rumbled across the space center, triggering cheers and gasps as well as car alarms in the parking lots.

In the hours that followed, Europa Clipper separated from the rocket, and more cheers erupted at NASA’s Jet Propulsion Laboratory when engineers acquired the first signal from the spacecraft, which indicated all systems functioning properly. A camera on the rocket captured a remarkable image of Europa Clipper, no longer sealed inside the rocket nose cone, growing smaller on the screen as it proceeded on its interplanetary voyage.

“We do everything to keep it protected, and now we send it on its way,” said Gina DiBraccio, acting director of NASA’s planetary science division, as she watched the NASA TV images showing the spacecraft heading toward interplanetary space.

The $5 billion mission, decades in the making, is designed to see whether Europa has the critical features considered necessary for life. The launch of the SpaceX Falcon Heavy rocket carrying the spacecraft had been scheduled for Thursday but was delayed ahead of Hurricane Milton’s landfall in Florida. The eye of the storm later made a direct hit on Cape Canaveral, Fla., and forced the closure of the space center.

NASA and SpaceX teams spent three days inspecting the rocket and the historic launchpad where Apollo astronauts long ago began their journeys to the moon. On Sunday afternoon, with the weather having turned splendid, NASA green-lit a Monday launch.

“That launch was incredible,” Europa Clipper chief scientist Robert Pappalardo of the NASA Jet Propulsion Laboratory said. “Now we’re on our way, and six years from now we’ll start getting great data from Europa.”

The spacecraft will go into orbit around Jupiter on April 11, 2030, and some months later will begin four years of collecting science data. The four-day delay due to the hurricane will not affect the timeline.

Europa Clipper will not land on the moon, but instead will go into a highly elliptical orbit of Jupiter that will enable 49 flybys of Europa, coming as close as 16 miles from the surface.

The scientific community has been fascinated by Europa for decades. Multiple lines of evidence suggest there is a deep, salty ocean beneath the surface. Although Europa is icy at the surface, tidal forces created by Jupiter’s immense gravity squeeze the moon’s icy crust and generate heat to keep the subsurface water liquid, scientists suspect.

Observations by the Hubble Space Telescope have raised the possibility that plumes of water vapor sometimes jet into space, and it is conceivable that the spacecraft could fly through such a hypothesized plume and sample material that originated below the surface.

NASA officials emphasize that this is not a life-detection mission. Instead, it is an effort to determine if Europa has the conditions amenable to life as we know it.

“We want to determine if Europa has the potential to support simple life in the deep ocean under its icy layer,” Mr. Pappalardo said in a prelaunch briefing Sunday. “We don’t expect fish and whales and that kind of thing.”

Europa has been studied by previous space probes, but Europa Clipper’s nine instruments are designed to deliver a trove of data that will vastly improve on what has been known about the moon previously, mission scientists said. Cynthia Phillips, a planetary geologist at the Jet Propulsion Laboratory and the mission’s project staff scientist, said a camera on Europa Clipper can produce images with 12 times the resolution of what NASA’s Galileo spacecraft obtained in the late 1990s.

“It’ll be able to see car-sized objects on the surface of Europa,” Ms. Phillips said.

The mission “is taking the icy moons into the realm of astrobiology,” said Thomas Zurbuchen, the former head of science at NASA, who attended the launch.

Asked whether he thinks Europa has the characteristics of a habitable world, or perhaps even life today, he stuck to the scientific method.

“My hope is the answer is yes,” he said. “But science doesn’t depend on hope.”

Although there may be molten rock deep inside Europa, “it seems very difficult for that magma to be able to ascend anywhere close to the ocean floor,” said Paul Byrne, a planetary scientist at Washington University in St. Louis who was an author on both papers.

Even if life did arise in Europa’s ocean long ago, “It seems challenging to sustain that life today,” Mr. Byrne said. “That's really what I think these studies are beginning to tell us.”

That does not mean Mr. Byrne thinks that Europa Clipper is a waste of $5 billion.

“Clipper is exactly the kind of mission we need to begin to incrementally build on our understanding of habitability,” he said, adding that he hopes it is the first in a “series of missions, not just to Europa, but so many of these so-called ocean worlds.”

The New York Times contributed.