Record-Tying Astronaut & Inventor of VASIMR Plasma Rocket
April 5, 1950 – Present
🇨🇷 Costa Rica / 🇺🇸 United StatesFranklin Ramón Chang-Díaz was born on April 5, 1950, in San José, Costa Rica, during an era when space exploration seemed impossibly distant for a boy from Central America. Growing up in Costa Rica's capital, young Franklin gazed at the night sky with wonder, dreaming of one day traveling among the stars. His grandfather, who had emigrated from China to Costa Rica, instilled in him the belief that with education and determination, any dream was achievable regardless of one's origins.
The moment that crystallized Franklin's ambitions came in 1969, when he watched Neil Armstrong and Buzz Aldrin walk on the Moon. He was 19 years old, and the Apollo 11 mission proved that humans could leave Earth and explore other worlds. At that moment, Chang-Díaz decided he would become an astronaut—an audacious goal for someone from a small Central American nation with no space program. But Franklin understood that the path to space ran through education, particularly in the United States.
With just fifty dollars in his pocket and speaking limited English, 18-year-old Franklin left Costa Rica for the United States in 1968. He enrolled at Hartford High School in Connecticut to improve his English, working multiple jobs to support himself while finishing his secondary education. His determination was extraordinary—he would wake before dawn to work, attend school during the day, and study late into the night, driven by his singular vision of reaching space.
Chang-Díaz's academic journey exemplified persistence and brilliance. He earned his bachelor's degree in mechanical engineering from the University of Connecticut in 1973, graduating with honors despite the financial and language barriers he faced. But he didn't stop there—he knew that to become an astronaut, he needed advanced training in cutting-edge science.
He pursued doctoral studies at the Massachusetts Institute of Technology (MIT), one of the world's premier scientific institutions. At MIT's Plasma Fusion Center, Chang-Díaz earned his PhD in applied plasma physics in 1977, studying nuclear fusion and plasma propulsion. His doctoral research focused on how superheated plasma—ionized gas at temperatures of millions of degrees—could be controlled using magnetic fields. This work would later become the foundation for his revolutionary rocket engine.
During his MIT years, Chang-Díaz applied to NASA's astronaut program multiple times and was rejected repeatedly. Most people would have given up, but Franklin understood that becoming an astronaut required not just qualifications but also timing and persistence. He continued his plasma physics research, building expertise that would make him uniquely valuable to NASA's future missions.
In 1980, after years of applications and rejections, Franklin Chang-Díaz was finally selected for NASA's astronaut program as part of the ninth astronaut class. He became the first Costa Rican astronaut and only the second Latin American ever chosen by NASA. The selection was validation of his decade-long journey from Costa Rica to the stars—proof that excellence and determination could overcome any barrier.
Chang-Díaz completed astronaut training in 1981, qualifying for Space Shuttle missions. But he would wait five more years before his first spaceflight, using the time to work on shuttle systems, develop spacewalk procedures, and continue his plasma physics research. His scientific background made him particularly valuable for technical missions involving research and International Space Station construction.
Franklin Chang-Díaz flew his first space mission in January 1986 aboard Space Shuttle Columbia (STS-61-C). The mission deployed satellites and conducted scientific experiments in microgravity. Seeing Earth from orbit—the blue planet suspended in the black void of space—fulfilled the dream that had driven Franklin since childhood. But this was just the beginning.
Over the next 16 years, Chang-Díaz flew six more missions, eventually tying the record for most spaceflights by any astronaut (seven missions, shared with Jerry Ross). His missions included STS-34 (1989), STS-46 (1992), STS-60 (1994), STS-75 (1996), STS-91 (1998), and STS-111 (2002). These missions had diverse objectives: deploying the Galileo spacecraft to Jupiter, conducting tethered satellite experiments, docking with the Russian space station Mir, and delivering equipment to the International Space Station.
Chang-Díaz logged 1,601 hours (66 days) in space, orbiting Earth over 1,000 times. He performed critical spacewalks, operated the Space Shuttle's robotic arm, and conducted scientific experiments in plasma physics and microgravity research. Each mission added to humanity's understanding of living and working in space, while advancing the construction of the International Space Station.
Throughout his astronaut career, Chang-Díaz never stopped thinking like a scientist. He understood that chemical rockets—the technology that had taken humans to the Moon and powered the Space Shuttle—had fundamental limitations. Chemical rockets provide enormous thrust but burn out quickly, making missions to Mars and beyond prohibitively long and dangerous. Astronauts would spend 6-9 months traveling to Mars, enduring radiation exposure and bone loss from prolonged weightlessness.
Drawing on his MIT plasma physics research, Chang-Díaz conceived of a revolutionary alternative: the Variable Specific Impulse Magnetoplasma Rocket (VASIMR). This plasma rocket would use radio waves to heat argon or hydrogen gas to millions of degrees, ionizing it into plasma. Powerful magnetic fields would then direct this superhot plasma out the back of the engine, creating thrust. Unlike chemical rockets that burn for minutes, VASIMR could operate continuously for months or even years.
The advantages of VASIMR are profound. While chemical rockets achieve high thrust but low efficiency, and ion drives achieve high efficiency but very low thrust, VASIMR can adjust its performance—trading thrust for efficiency or vice versa as needed. For deep space missions, VASIMR could operate continuously at high efficiency, dramatically reducing travel times. Calculations suggest VASIMR could cut a Mars trip from 6-9 months to just 39 days—a game-changing improvement that would reduce radiation exposure, psychological stress, and mission costs.
In 2005, Chang-Díaz retired from NASA after 25 years to focus on developing VASIMR technology. He founded Ad Astra Rocket Company (the name means "to the stars" in Latin) to commercialize the plasma rocket. The company, headquartered in Texas with research facilities in Costa Rica, has spent nearly two decades refining VASIMR technology.
Ad Astra has successfully tested increasingly powerful VASIMR prototypes, demonstrating the engine's viability. The VX-200 prototype achieved 200 kilowatts of power, while current designs target megawatt-class engines capable of powering crewed missions to Mars. NASA has provided funding for VASIMR development, recognizing its potential for future deep space exploration.
Beyond Mars missions, VASIMR has applications for satellite station-keeping (maintaining orbital positions), space debris removal, and potential lunar missions. The technology represents a paradigm shift in space propulsion—moving from explosive chemical reactions to controlled plasma physics, from brief bursts of thrust to sustained acceleration over months.
In Costa Rica, Franklin Chang-Díaz is a beloved national hero and inspiration to millions. A country of five million people, Costa Rica has no military and invests heavily in education and environmental protection. Chang-Díaz embodies Costa Rican values: peace, education, innovation, and international cooperation. His success proved that Costa Ricans could compete at the highest levels of global science and exploration.
Chang-Díaz has worked to build Costa Rica's scientific infrastructure, establishing Ad Astra's research facilities there and advocating for STEM education. He serves as a role model showing young Costa Ricans and Latin Americans that space exploration is not limited to superpowers—that talent, education, and determination can take you anywhere, even to the stars.
Dr. Chang-Díaz demonstrated that astronauts can come from any nation and invented revolutionary plasma rocket technology that could reduce Mars trips from 6-9 months to just 39 days, transforming deep space exploration.
Franklin Chang-Díaz's legacy operates on multiple levels. As an astronaut, he proved that space exploration belongs not just to superpowers but to anyone with the skill, education, and determination to reach for the stars. Coming from Costa Rica—a small, peaceful nation without a space program—Chang-Díaz showed that excellence knows no borders and that the cosmos welcomes explorers from all nations and backgrounds.
His seven spaceflights contributed directly to humanity's expansion into space. He helped build the International Space Station, conducted critical research, and participated in historic U.S.-Russian cooperation that transformed former Cold War adversaries into partners in exploration. These missions demonstrated that space can unite humanity in common purpose rather than dividing us along national or ideological lines.
The VASIMR plasma rocket represents Chang-Díaz's most profound technical legacy. If successful, VASIMR will revolutionize deep space exploration. Current chemical rockets make Mars missions dangerous endurance tests—astronauts spending 6-9 months in transit, exposed to cosmic radiation and bone-weakening microgravity. VASIMR's potential to reduce this to 39 days transforms Mars from a suicide mission into a realistic goal, protecting astronauts' health while dramatically reducing mission costs and complexity.
Beyond Mars, VASIMR technology could enable missions to the asteroid belt, Jupiter's moons, and eventually beyond the solar system. The continuous-thrust capability means spacecraft could accelerate halfway to their destination, then flip and decelerate the rest of the way—mimicking science fiction faster than anyone imagined possible with near-term technology. This could open the solar system to human exploration within our lifetimes.
For Costa Rica and Latin America, Chang-Díaz represents inspiration and proof that the region can contribute to humanity's greatest endeavors. He has worked to build Costa Rica's scientific capacity, establishing research facilities and advocating for STEM education. His message to young Latin Americans is clear: your dreams are not limited by your birthplace, your economic circumstances, or others' low expectations. With education, hard work, and persistence, you can reach any goal—even the stars.