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Chang-Díaz, Franklin

Franklin Chang-Díaz

Born April 5, 1950 (San José, Costa Rica)

Costa Rican-born American astronaut, physicist

While growing up in Costa Rica and Venezuela, Franklin R. Chang-Díaz dreamed of exploring space. He achieved his goal when he became an astronaut in the United States, eventually completing seven space shuttle missions in 2002 and tying the world record for the most trips in space. As the director of the Advanced Space Propulsion Laboratory at the National Aeronautics and Space Administration (NASA) Johnson Space Center, he conducts research on conquering the next space frontier: human flights to Mars. Chang-Díaz is a national hero in his native Costa Rica.

"Humans began exploring space the day they chose to walk out of their caves in search of food. Space exploration is nothing less than human survival."

Inspired by "Atoms for Peace"

Franklin R. Chang-Díaz was born on April 5, 1950, in San José, Costa Rica, the son of Maria Eugenia Díaz and Ramón Chang Morales, an oil worker of Costa Rican-Chinese descent. When Franklin was about one year old, the family moved to Venezuela. In 1957, while they were living in Venezuela, his mother told him about the launch of the Sputnik 1 Soviet satellite. The first man-made craft to orbit Earth, the satellite captured the imagination of six-year-old

Franklin. Climbing a mango tree, he gazed at the sky for hours in search of Sputnik.

By the time the family returned to Costa Rica, Chang-Díaz was already interested in science. When he was in grade school he had an experience that shaped his life. In 2003 he recalled this experience in a speech on rocket research that he gave to the U.S. House of Representatives Subcommittee on Energy: "A traveling scientific exhibition, sponsored by the United States, was set up in a large inflatable dome at the national airport in San José," Chang-Díaz told his audience. "It was entitled 'Atoms for Peace' and was sent throughout Latin America to inform and educate the public about atomic energy. The exhibition spent several days in the country and, while it was there, every day after school I delighted myself in examining the new universe of atomic particles, their magical and amazing power for converting their mass into energy."

An equally important event took place when Chang-Díaz was in high school and found a NASA brochure titled "Should You Be a Rocket Scientist?" It was written by Wernher von Braun (1912–1977; see entry), the leading rocket researcher of the time. The scientist was then living in the United States after an earlier career developing the V-2 rocket for Nazi Germany. Chang-Díaz told the energy subcommittee members, "I immediately sent [von Braun] a letter with a resounding 'yes.' The NASA form letter response … came months later and had a simple message: to pursue such a career I would have to come to the United States."

After completing high school in Costa Rica, Chang-Díaz decided to earn some money so he could travel to the United States and attend college. Taking a job at the National Bank of Costa Rica, he saved fifty dollars in eight weeks.

Chang-Díaz moved to Hartford, Connecticut, where he lived with an uncle and cousins. He spoke no English, however, and he lacked sufficient academic credits to enter an American university. In order to learn English he enrolled in transitional classes as a senior at Hartford High School. Chang-Díaz impressed his teachers with his performance in mathematics and science, so they urged him to apply for a scholarship at the University of Connecticut. Admissions officials granted the scholarship because they thought Chang-Díaz was from Puerto Rico and therefore a U.S. citizen. Upon learning that he was from Costa Rica, they withdrew the offer. Finally his Hartford teachers persuaded the university to accept him.

Chang-Díaz entered the University of Connecticut in 1969 and obtained a bachelor of science degree in mechanical engineering four years later. In 1977 he earned a doctorate in plasma physics (science that deals with the structure and interaction of plasma, a collection of charged particles that resembles some gases) at the Massachusetts Institute of Technology (MIT). He immediately applied to the NASA astronaut program, but he was not accepted. Chang-Díaz then joined the Charles Stark Draper Laboratory, where he conducted research on a fusion reactor (a device that converts the nucleus of an atom to usable energy) technology. During this time he married his first wife, the former Canoce Buker; after their divorce, he later married Peggy Doncaster. He is the father of four children.

Ties space-flight record

In 1980 Chang-Díaz reapplied to the astronaut corps and was accepted as one of only nineteen candidates from three thousand applicants. During his astronaut training he worked at the Shuttle Avionics Integration Laboratory, and he contributed to early design studies for the International Space Station (ISS; see entry). (A space station is a large artificial satellite, or a body that orbits in space; it is designed to be occupied for long periods and to serve as a base for conducting research. The International Space Station, completed in 1998, is used by various nations for research.) In 1982 he was named to the support crew (astronauts who assist the pilot and copilot) for the first Space Lab mission (a research laboratory in space). He went on to fly seven space shuttle missions between 1986 and 2002. (A space shuttle, also called a shuttle orbiter, is a space plane that transports cargo and passengers between Earth and space. NASA has operated five space shuttles: Discovery, Challenger, Columbia, Atlantis, and Endeavour. Enterprise was the first shuttle to be built; however, it never went into orbit and was used primarily for "captured flights" involving takeoff and re-entry exercises.)

Chang-Díaz's first flight, in 1986, was a six-day mission aboard the Columbia. The space shuttle completed ninety-six orbits of Earth and launched the SATCOM KU (a satellite used to make observations pertaining to astronomy, the ionosphere [the part of Earth's atmosphere in which radiation waves are converted into ions, or positive and negative electrons], Earth's atmosphere, the Sun, and other scientific areas). His next flight was in 1989 on the space shuttle Atlantis. He and fellow crewmembers deployed (launched in space) the Galileo, an unmanned satellite programmed to explore the planet Jupiter. Completing seventy-nine orbits, the Atlantis crew also operated the Shuttle Solar Backscatter Ultraviolet Instrument, which mapped ozone (a gas that produces air

pollution) in Earth's atmosphere. Again aboard the Atlantis, Chang-Díaz helped to launch the European Retrievable Carrier satellite and test the first Tethered Satellite System. (The European Retrievable Carrier satellite contained experiments for studying microgravity [the virtual absence of gravity], the Sun, and matter. The Tethered Satellite System consists of a small satellite attached to the space shuttle with a tether, or connecting cable; it is a tool for research in space plasma physics.) Lasting eight days in 1992, this mission involved 126 orbits of Earth.

Chang-Díaz's fourth mission, in 1994, was on the space shuttle Discovery, which completed 130 orbits of Earth. The first joint U.S.-Russian space shuttle mission to include a Russian cosmonaut (astronaut) as a crew member, it was also the first flight of the Wake Shield Facility (a disc-shaped

platform for the development of space-based manufacturing of film materials) and the second flight of the Space Habitation Module-2 (Spacelab 2; used to carry equipment for the International Space Station). During the mission Chang-Díaz participated in several experiments involving biological materials, Earth observation, and life science. His next flight was aboard the Columbia, which completed 252 orbits of Earth in 1996. On this fifteen-day mission the shuttle crew conducted additional Tethered Satellite System experiments. In addition, they conducted research with the U.S. Microgravity Payload, which provided information that helps improve the production of medicines, metal alloys (combinations of metals), and semiconductors (solids that act both as conductors and as insulators of electrical energy).

In 1998 Chang-Díaz flew on the Discovery. It was the ninth and final mission for the U.S. space shuttle and the Russian space station Mir in the first phase of the joint U.S.-Russian space shuttle program. Chang-Díaz and other Discovery crewmembers brought supplies and equipment to Mir. They also ran experiments on the Alpha Magnetic Spectrometer, the first research project of its kind on antimatter (matter composed of subatomic particles) in space. Chang-Díaz took his seventh flight, on the Endeavor, in June 2002. He tied a record for the number of space flights set by U.S. astronaut Jerry Ross (1948–; see box on this page) the previous month. During the twelve-day mission, Chang-Díaz participated in three space walks.

Jerry Lynn Ross

In June 2002 Franklin R. Chang-Díaz tied the world record of seven space flights set by U.S. astronaut Jerry Lynn Ross (1948–) the previous month.

Ross is a Crown Point, Indiana, native and Purdue University graduate who joined the astronaut corps in 1980. From 1985 through 2002 he flew seven missions aboard the space shuttles Atlantis, Columbia, and Endeavor. During an Atlantis flight in 1991 he helped deploy the 35,000-pound Gamma Ray Observatory (an orbiting telescope that observes high-energy radiation) and to test prototype space station Freedom hardware. In 1993 he flew aboard the Columbia on a German-sponsored Space Lab mission. Ross and the crew conducted nearly ninety experiments in areas such as physics, robotics, astronomy, and Earth and its atmosphere. Two years later he flew on the Atlantis during the second U.S. space shuttle mission to rendezvous and dock with the Russian space station Mir. In 1998 Ross was involved in assembling the International Space Station. By 2002 he had spent 58 days in space.

Conducts pioneering research

In 1993, at the height of his astronaut career, Chang-Díaz was appointed director of the Advanced Space Propulsion Laboratory at the NASA Johnson Space Center in Houston, Texas. He supervises research on plasma rocket engines. Advanced Space Propulsion Laboratory research could lead to technology that would significantly reduce the amount of time required to travel from Earth to Mars. Rockets using chemical-based propulsion can achieve a speed of only ten thousand miles per hour. At this rate, a trip to Mars would take at least ten months each way. Higher rocket speeds could be reached if a spacecraft's propellant (the substance used to power the craft into space) were superheated, but the extreme heat would melt the rocket. After more than twenty years of research and experimentation, Chang-Díaz may have found a solution—the variable specific impulse magnetic resonance (VASIMR) propulsion system. Chang-Díaz and his team discovered that the VASIMR prevents a rocket from melting by using magnetic fields (portions of space where magnetic forces can be detected) to contain and guide propellant gases. The VASIMR can be compared the process to that of a microwave oven.

With a VASIMR engine, rockets could achieve speeds of 650,000 miles (1,045,850 kilometers) per hour. At the same time, VASIMR's superior fuel efficiency would significantly reduce the weight of the spacecraft and decrease the high cost of space missions. Chang-Díaz calculated that a VASIMR-powered mission to Mars, including one spacecraft for astronauts and another for supplies, would weigh only about four hundred tons (362.8 metric tons), half the weight of an earlier spacecraft design for a Mars mission. VASIMR technology could cut the time of a mission from Earth to Mars from ten months to only ninety-three days. Chang-Díaz has predicted that the VASIMR could be ready for a Mars flight in 2018. This achievement would fulfill the dream of Robert Goddard (1882–1945; see entry), the American physicist who launched the first liquid-propellant rocket in 1926. Goddard's inspiration for conducting his rocket experiments was sending a person to Mars.

Chang-Díaz works in other areas of space-related research as well. He travels widely in the United States, Mexico, and Latin America, speaking on the importance of sharing space age technologies with developing nations. In 1991, while visiting Costa Rica, he became interested in finding a cure for Chagas's disease. It is caused by a parasite (an organism that lives within another organism) called Trypanosoma and kills some 45,000 people a year, mostly in Latin America. Because the microgravity (virtual absence of gravity) of space creates ideal conditions for the production of crystals (the basic structure of some drugs), Chang-Díaz theorized that the space shuttle could become an important laboratory for studying Chagas's disease. On the Columbia flight in 1996 he and NASA biochemist Lawrence J. DeLucas (1950–) started a study of proteins (complex substances in plants and animals) made by the Chagas parasite, but they did not have time to complete the experiment. Astronauts on four later flights, however, made crystal forms of an enzyme (a complex protein that produces a chemical reaction in the body) produced in the disease and researched compounds that could be used in treatment. Chang-Díaz predicted that the Chagas project could lead to other innovations, such as new agricultural techniques based on study of the interconnection of rain forests (tropical woodlands with rainfall of at least 100 inches annually), biodiversity (an environment that contains numerous plants and animals), and space.

Chang-Díaz has been active in community service throughout his career. In 1987 he founded the Astronaut Science Colloquium Program to build closer relationships between astronauts and scientists. The following year he helped organize the Astronaut Science Support Group to utilize the expertise of astronauts who have flown space shuttle missions. The group advised the National Space Transportation System and the Space Station programs on science and technology issues. For two and one-half years he was a house manager in an experimental residence for people with severe mental illness who were being released from institutionalized care. He has also been an instructor and advisor in a Massachusetts rehabilitation program for Hispanic drug abusers.

Promotes space education

Along with fellow team members at the Johnson Research Center, Chang-Díaz introduced a space-education program at Odyssey Academy, a predominantly Hispanic middle school in Galveston, Texas. Twenty students from the sixth, seventh, and eighth grades were chosen for participation in eleven weeks of classes on plasma rockets. Each class was taught by two members of the team. As Chang-Díaz reported to the House Subcommittee on Energy in 2003, the project was so successful that the Johnson Space Center is planning to expand the program to other schools in the area.

A strong advocate of space education for the younger generation, Chang-Díaz closed his statement with these words: "Humans began exploring space the day they chose to walk out of their caves in search of food. Space exploration is nothing less than human survival. You probably have heard us say that the first human being to set foot on Mars is alive now somewhere on planet Earth, a young girl or boy sitting in one of our classrooms at this very moment. Will they be discouraged or encouraged by their elders? I was blessed with the best parents anyone could ever have and perhaps fortunate to find a traveling display on atomic power and a NASA brochure on rocket science to keep nudging me on."

The recipient of numerous honors and awards—including two NASA Distinguished Service Medals (1995, 1997), the Liberty Medal (1986), and the Medal of Excellence from the Congressional Hispanic Caucus (1987) in the United States—Chang-Díaz was named "Honorary Citizen" by the government of Costa Rica in 1995. This is the highest award given by Costa Rica to a foreign citizen, and since the astronaut came from that country he became the first honoree who was born there. In addition to his work at Johnson Space Center, Chang-Díaz is a part-time professor of physics at Rice University in Houston, Texas, and the University of Houston. He has also presented papers at technical conferences and published articles in scientific journals.

For More Information


"2000 Hispanic Achievement Award." Hispanic Magazine (July 2000): p. 80.

Chang, Kenneth. "Novel rockets speed dreams of sending people to Mars." The New York Times (June 20, 2000): p. D5.

Eng, Dinah. "From Jungle to Space in Pursuit of New Drugs." The New York Times (November 28, 2000): p. F8.

Web Sites

"Astronaut Statistics." Encyclopedia Astronautica. (accessed on June 29, 2004).

"Franklin Chang-Díaz (Astronaut)." (accessed on June 29, 2004).

"Jerry Lynn Ross." Encyclopedia Astronautica. (accessed on June 30, 2004).

"Statement of Franklin Chang-Díaz before the Subcommittee on Energy, Committee on Science, House of Representatives." House Committee on Science. (accessed on June 29, 2004).

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