saturn rings cassini nasa roman tkachenkoThe last full view of Saturn taken by NASA's Cassini spacecraft.NASA/JPL-Caltech/Space Science Institute; Roman Tkachenko

  • Linda Spilker began researching Saturn at NASA's Jet Propulsion laboratory four decades ago.
  • She worked on the Voyager mission and was on the Cassini mission to Saturn, which recently ended, from start to finish.
  • Because there's a chance alien life may exist at Saturn's moon Enceladus, Spilker has proposed a NASA mission to return to the world.

Wielding a fresh Bachelor's degree in physics, a 22-year-old woman walked into NASA's Jet Propulsion Laboratory in 1977 and interviewed for a job.

Staff at the lab looked over her resume and offered the young woman a choice. Would she like to join an existing mission at Mars, called Viking — or a brand-new mission called Voyager?

"Well, where is Voyager going?" the woman asked. Jupiter, Saturn, and possibly onto Uranus and Neptune, a staff member said.

She remembered peering at Saturn through a tiny telescope in third grade. Intrigued by the world, she made her choice.

linda spilker scientist Spilker_Linda_14.JPGPlanetary scientist Linda Spilker.NASA/JPL-Caltech

Saturn would guide Linda Spilker, now 62, to be many things over the next 40 years — planetary scientist, imaging expert, author of dozens of scientific studies, recipient of more than 20 professional awards. She'd also become one of many "Voyager moms" who synced the birth of her kids to a rare planetary alignment.

After Voyager, Spilker became a vital mind behind the nuclear-powered Cassini mission, which NASA launched toward Saturn in 1997 and recently destroyed.

Her efforts helped find a warm, salty ocean hiding beneath the icy crust of Saturn's moon Enceladus, something she's described as "one of the most astonishing discoveries" in space exploration.

"I feel remarkably lucky. Right place, right time, right education," she said. "I wouldn't trade it for anything."

In a wide-ranging interview with Business Insider, Spilker reflected on the history of Voyager and Cassini, battling sexism, balancing work and family life, and pushing to answer humanity's most evocative question: Are we alone?