Are We Alone In The Universe? Exploring Jupiter's Moon Europa

In 2015, Bill Nye found himself aboard Marine One, the iconic helicopter of the U.S. President, soaring over the scenic Pacific Northwest. Officially, he was there to attend an Earth Day event, but Nye—ever the indefatigable science advocate—had space exploration on his mind. Next to him sat President Obama, and Nye seized the opportunity to champion a cause that had captured the imagination of scientists for decades: a mission to explore Jupiter’s icy moon, Europa. At that time, it was a proposal on shaky financial ground, but Nye’s passion for the project was unwavering.

“There are two questions: Where did we come from? And are we alone in the universe?” Nye later remarked about his conversation with the President. Questions of cosmic significance, no doubt, but for Nye and countless scientists, they are far more than rhetorical. They are at the heart of one of NASA’s most ambitious missions, which has now moved from mere fantasy to a nearly realized dream. That dream is the Europa Clipper—a $5 billion mission to explore one of the most promising candidates for extraterrestrial life in our solar system.

Europa is no ordinary moon. Orbiting the gas giant Jupiter, it is a frozen world. On the surface, it looks desolate, an icy wasteland untouched by life. But beneath that surface lies a vast ocean, miles deep, heated by the tidal forces exerted by Jupiter’s gravity. That ocean, scientists believe, is a potential incubator for life. And it’s that hidden sea that the Europa Clipper is designed to explore.

The Clipper spacecraft, engineered by NASA’s Jet Propulsion Laboratory (JPL), is the largest interplanetary probe ever constructed by the agency. Once it launches, the spacecraft will embark on a five-and-a-half-year journey to Jupiter, using gravity assists from Mars and Earth to slingshot toward its destination. Upon arrival, it will perform 49 flybys of Europa, coming as close as 16 miles to the moon’s surface. With each pass, Clipper’s sophisticated instruments will collect crucial data about Europa’s icy shell and the ocean beneath it.

“Clipper is going to be the first in-depth mission that will allow us to characterize habitability on what could be the most common type of inhabited world in our universe,” said Gina Dibraccio, acting director of NASA’s Planetary Science Division. If life exists in that cold, dark ocean, it could reshape everything we know about biology. It might even suggest that life could be common across the universe, lurking in the most unexpected of places.

But the journey to get the Clipper mission off the ground has been anything but smooth. Europa first piqued scientists' interest during the Galileo mission in the 1990s, when the spacecraft flew past the moon and sent back tantalizing data. Observations suggested the existence of a subsurface ocean, sparking dreams of a dedicated mission to study Europa in detail. But space exploration is as much about politics and budgets as it is about science. In the 2010s, NASA’s focus was elsewhere, with its budget being squeezed and other flagship missions, like the Curiosity Mars Rover and the James Webb Space Telescope, draining funds.

By 2014, it looked like a Europa mission was dead in the water. NASA even told Congress explicitly that it wasn’t going to fund the project. That’s when The Planetary Society, with Nye as its CEO, sprang into action. The Pasadena-based nonprofit, dedicated to space exploration advocacy, mounted a campaign to keep Europa alive in the minds of both the public and Congress. “We realized that this [mission] would be possible 10 years ago at The Planetary Society,” Nye explained, “and so we just got on it: 'look, everybody, write letters, write emails, talk with your congressmen, come to our days of action’”.

The lobbying efforts worked. In 2015, Congress finally allocated the first significant funding for the mission, thanks in no small part to a space-loving Texas congressman who used his influence to secure $100 million for the project. NASA turned to JPL, which had become the go-to centre for developing complex robotic missions, to design and build the spacecraft.

Now, with the Clipper set for launch, the scientific excitement is palpable. Once Clipper begins its Europa flybys, the mission’s primary goal will be to confirm the presence of the ocean beneath the moon’s icy surface. The spacecraft will measure the magnetic field produced by the salty water beneath the ice, as well as the gravitational pull that Europa exerts on Clipper. But that’s only the beginning. The probe will also search for organic molecules—the essential building blocks of life—that may have been blasted into space by Europa’s famed ice geysers.

“If there is something alive—imagine a Europanian microbe, let alone Europanian fish people—these things would be shot into space,” Nye quipped in his usual humorous style. While NASA has no expectations of finding "fish people," the discovery of even the tiniest microbe would have a seismic impact on our understanding of life. It could mean that life, rather than being a rare fluke, is a common occurrence in the universe, flourishing in the unlikeliest of places.

Still, the mission isn’t just about looking for aliens. Europa Clipper will also study the moon’s icy crust, mapping it in unprecedented detail. Using penetrating radar, much like an X-ray, the spacecraft will peer deep into the ice to understand how the ocean interacts with the crust above it and the rocky mantle below. It’s a feat of engineering that could help us unlock the geological mysteries of other icy worlds in the outer solar system.

But as Clipper prepares to leave Earth, there’s a larger context weighing on NASA and JPL. The agency is currently facing significant budget constraints. Flagship missions like this are becoming increasingly rare as NASA shifts its focus to human spaceflight. In fact, Clipper might be one of the last multibillion-dollar flagship missions for the foreseeable future. A report ordered by Congress recently criticized NASA for neglecting critical infrastructure and workforce investments in favour of high-cost missions. With fewer large-scale projects in the pipeline, the future for JPL is uncertain.

That uncertainty echoes a similar period in the 1980s when JPL was struggling to survive. Back then, the lab’s flagship mission, Galileo, was nearly canceled due to budget cuts. But thanks to a powerful political ally—a Caltech trustee with connections in Congress—JPL was saved, and Galileo went on to revolutionize our understanding of Jupiter and its moons . Europa Clipper, in many ways, is Galileo’s spiritual successor. But this time, JPL might not be so lucky in finding a political saviour.

For now, though, the focus is on Europa. After years of lobbying, advocacy, and engineering marvels, the mission is finally poised to explore the frozen moon. If life exists out there, even in the form of the tiniest microbes, it could change everything we know about biology, evolution, and the place of humanity in the universe.

As Bill Nye so succinctly put it, “If we find life in another world, it will change life in this one”. The Europa Clipper may just be the key to answering one of humanity’s oldest and most profound questions: Are we alone?