Inside JPL: The Lab Behind Every Mars Rover

7 days ago
4 min read

Tucked into the foothills of the San Gabriel Mountains near Pasadena, California, sits a research campus responsible for some of the most famous machines humans have ever built. Every Mars rover, most spacecraft that have visited another planet, and the network that talks to them across billions of miles of space all trace back to one place: NASA's Jet Propulsion Laboratory, known simply as JPL. After a rough few years of budget cuts and a paused public program, JPL is throwing its doors back open to visitors in October 2026, and the story of how it got here is almost as interesting as the spacecraft themselves.

How JPL Got Started

JPL is actually older than NASA itself. It began in 1936, when a small group of Caltech graduate students started experimenting with rocket propulsion in the hills above Pasadena. Their tests were dangerous enough, involving early rocket fuel that had a habit of exploding, that people around campus nicknamed them the "Suicide Squad." That risky, scrappy research eventually grew into a full scale laboratory operated by the California Institute of Technology.

In 1958, Congress created NASA, and JPL, which had just helped build and launch Explorer 1, the first satellite launched by the United States, became part of the new space agency. Caltech kept managing the day to day operations, a partnership that has lasted for decades under a federal contract that gets periodically renewed.

What JPL Actually Does

JPL is best known as NASA's center for robotic exploration of the solar system, meaning missions that do not carry astronauts but instead rely on spacecraft, rovers, and orbiters to explore other worlds. Over the decades, JPL has built and operated missions like Voyager, which is now the farthest human made object from Earth, Cassini, which spent 13 years studying Saturn, and the Mars rovers, including Curiosity and Perseverance, which are still exploring the Martian surface today.

Beyond building spacecraft, JPL runs the Deep Space Network, a system of giant satellite dishes positioned around the globe that sends commands to and receives data from spacecraft scattered throughout the solar system. JPL engineers also develop technology used closer to home, including instruments that monitor Earth's climate, oceans, and atmosphere. On top of the space missions, the lab operates a Microdevices Laboratory that builds miniature technologies and a Machine Shop where precision spacecraft parts are manufactured, all in service of the same basic goal, using science and engineering to explore places humans cannot easily reach.

The Rough Stretch That Led to the Shutdown Talk

Over the past couple of years, JPL has been through a genuinely difficult stretch, and that turbulence is likely why the idea of the lab "closing" has been floating around. Starting in late 2023 and continuing through 2024 and 2025, JPL went through several rounds of layoffs driven by federal budget cuts, cutting its workforce by roughly a quarter. In one memo, the lab's director noted that funding for its Mars program had been cut by more than 60 percent compared to a few years earlier.

On top of the budget troubles, a major wildfire added a literal closure to the mix. In January 2025, the Eaton Fire forced JPL to evacuate and shut its campus for a stretch of mandatory telework, though the facility itself avoided direct fire damage. Then in May 2026, NASA announced an even bigger shake-up, revealing it would open up competitive bidding for who manages JPL once Caltech's current contract expires in 2028, ending a management arrangement that had been in place since the lab's earliest days. None of this means JPL itself shut down. The lab has kept running its missions the entire time. What actually went dark was something more specific: JPL's public open house program.

What's Really Reopening in 2026

For decades, JPL invited the public onto its campus for a free, hugely popular open house where visitors could walk through mission control, see full-scale rover replicas, and peek inside real spacecraft assembly facilities. That event paused in 2020 because of the pandemic, made a brief one-time return in the spring of 2023, and then went quiet again.

Now, as JPL celebrates its 90th anniversary, the open house is coming back under the name Explore JPL, scheduled for October 10 and 11, 2026. Visitors will be able to tour the Space Flight Operations Facility, nicknamed the Center of the Universe, where engineers track spacecraft billions of miles away, along with the Spacecraft Assembly Facility, the Machine Shop, and the Microdevices Laboratory. Because demand for tickets has been enormous in past years, JPL uses a free, timed ticket system, with registration opening in late August 2026 and tickets typically claimed within minutes.

Why This Moment Matters

JPL sits at an interesting crossroads. It is simultaneously celebrating nine decades of exploration, welcoming the public back after years of closed doors, and facing real uncertainty about its funding and future management. That mix of celebration and challenge is common in big scientific institutions, where budget politics and public excitement can exist side by side. For the thousands of people hoping to snag a ticket to Explore JPL this October, the reopening is a rare chance to see, in person, the birthplace of machines that have touched every planet in the solar system.

The Bottom Line

JPL never actually closed its doors on its science, even through layoffs, a wildfire evacuation, and a major contract shake up. What did pause, for years, was the public's chance to walk through it, and that is exactly what is returning in October 2026. Ninety years after a group of daring Caltech students started testing rockets in the hills above Pasadena, the lab they built is still sending spacecraft to the edges of the solar system, and now it is ready to show the public how it happens.