Of all the gravity-defying wings displayed at the Smithsonian’s National Air and Space Museum, the prettiest were forged by nature in outer space. Tiny when compared with the spread of the pioneering Wright brothers’ plane or the globe-circling Voyager, they emerged in orbit, and belong to a trio of diminutive painted lady butterflies.
Now perched in the "Where Next, Columbus?" gallery, which explores the potential for human travel to Mars, the first butterflies in space provided the final data points of a student-run experiment that flew aboard the space shuttle Columbia’s STS-93 mission in July 1999. They symbolize a renaissance of interest in microgravity research as we enter the era of the International Space Station.
Gravity keeps the Moon, the shuttle and the space station in orbit around Earth, and—despite loose talk of "zero gravity"—still exists during the weightlessness of spaceflight. In fact, gravity’s pull at the altitude typical of shuttle orbits is about 90 percent that on Earth’s surface. But an object in orbit travels at such speeds as to negate almost all of this tug by sustaining a free fall—not toward Earth but around it. Such a condition of persistent microgravity is nearly impossible to reproduce anywhere within the planet’s atmosphere.
So, from the Skylab program of the 1970s to the Russian Mir Space Station (which recently plunged into the South Pacific), to the International Space Station now being deployed—and on many of the shuttle flights in between—scientists have taken advantage of these orbiting microgravity laboratories, extending the privilege even to a group of high school students studying butterflies.
The butterflies’ incredible migration began in the fall of 1997 in a classroom in Albany, Georgia. There, a team from Dougherty County’s high schools—composed of 15 students from a program designed to encourage youth with learning or physical disabilities toward careers in science and technology—set out to determine if a lack of gravity would affect metamorphosis. Might Kafkaesque supernormal bugs result? Would shape or colors change or wings be stunted or weak? Would the caterpillars, which normally climb upward and use gravity to build their chrysalises downward, be disoriented and unable to adapt?
Aided by area scientists and dedicated teachers, the pupils designed over the course of a year a very compact experiment to monitor five painted lady caterpillars and five chrysalises of varying ages. The flight itself would last five days. Assuming the role of payload specialists, students such as Leon Douglas and Julie Blackburn took the critters home at night to better understand metamorphosis, and to iron out details of the experimental design.
Spending time with both the creatures and their container allowed students to notice something that otherwise might have been missed: that the alignment of the screws and holes in at least one place in the Lexan holding box allowed caterpillars to escape. The students also figured out how to anchor the chrysalises within the box: a steel crossbar, treated with a sticky substance, to which the chrysalises could be affixed. Technicians made the necessary changes, and the experiment went forward.
Although an amateur event, the pressure was big league. The young Georgians were overseeing one of two premiere experiments in a program called S*T*A*R*S, or Space Technology and Research Students. The program was started by SPACEHAB, Inc., a Houston, Texas-based company that builds, owns and operates the reusable pressurized modules that fit in the shuttle cargo bay. The double module used on the shuttle houses up to 10,000 pounds’ worth of microgravity and life science experiments per flight, including the student projects. While other student experiments have been launched into orbit, the S*T*A*R*S program takes advantage of the Internet by "Webcasting" nearly real-time images of the experiments to the student-researchers—and countless other students at schools around the world.
Before the scheduled launch, the Georgia students took a bus to the Kennedy Space Center in Florida to see off their space-faring creatures. But moments before liftoff, a sensor warned of a hydrogen leak. It turned out to be a false alarm, but in the meantime, the launch was delayed. Bad weather scuttled the second countdown. Ready for myriad snafus, the students restocked the research habitat with new sets of specimens, synchronized for the appropriate stages in their 21- to 22-day life cycle. Finally, on a third attempt, the shuttle blasted off.
Prior microgravity experimentation made some degree of success likely. Popular views are of astronauts floating while catnapping, or working robotic arms. But NASA’s elite often manipulate specially designed test tubes, petri dishes and creature cages aboard the space shuttles for the sake of basic science and commercial research. On John Glenn’s famous 1998 return to space flight—which the students watched blast off from Florida’s Cape Canaveral in preparation for their experiment—the Senator helped conduct research on new space-age materials.
Before the painted ladies (Cynthia cardui), other less beautiful creatures had already ventured into space. Arabella and Anita, two notorious spiders, learned how to construct normal webs aboard Skylab, a U.S. space station launched into Earth’s orbit in 1973. Subjects in other Skylab experiments that followed—some of which can be found in the Smithsonian’s collections—included fish, monkeys, ants and bees.
In the wake of the Apollo moon shots, the Skylab program demonstrated the feasibility of spending at least several months in space. Astronauts on Skylab conducted nearly 300 distinct investigations, including 19 student experiments.
When the program was abandoned in the mid-1970s, NASA turned to shuttle flights and experiments in Spacelab research modules (which were eventually replaced by the larger SPACEHAB modules). Meanwhile, the Russian space agency extended flight durations for their cosmonauts, keeping them orbiting for more than a year at a time on the Salyut space stations and then on Mir.
Now that the International Space Station has begun 15 years of continuous habitation, many speculate that microgravity research will not only help humans travel to or even inhabit Mars but will also help them on Earth. Everything from developing advanced atomic lasers and new immunotherapies to growing three-dimensional tissues and even organs in space may eventually be possible.
The multibillion dollar station, which will ultimately weigh in at 470 tons, is expected to foster unprecedented long-term research facilities and collaborations between the participating American, Russian, European, Japanese, Canadian and Brazilian space agencies.
In February of this year, the first of six research modules—this one dubbed Destiny—was attached to the International Space Station, enabling crews to begin full-time research, with as many as 12 racks devoted to ongoing experiments.
Though much microgravity research will continue to be done on or near Earth—in bioreactors, drop towers, and special aircraft and rocket trajectories—these venues provide only short-lived seconds of near zero gravity conditions. The Space Station will increasingly provide opportunities to conduct research in these conditions that spans weeks and months, even years.
Freed from the limits of gravity, many substances behave differently, because subtle forces become unmasked. For instance, diffusion is the natural tendency of materials to spread themselves evenly in a fluid. But on Earth, this effect is tempered by the gravity-induced facts of sedimentation and buoyancy, which separate materials from one another based on their density. In space, scientists can study pure diffusion. Likewise, research in combustion science, molecular biology and fundamental physics—among other fields—can benefit greatly from a nearly gravity-free environment. That basic research, in turn, may lead to more efficient ways of creating and processing materials here on Earth—and in space.
Most of the early experiments will focus on how microgravity conditions might affect crew members on long voyages. Still, much of that research may have implications for the rest of us. It seems that the absence of gravity affects the human body in ways that mimic degenerative diseases prevalent among the elderly, including bone loss, balance problems and weakened immunity. As countermeasures are developed for astronauts, better treatments for osteoporosis and spinal cord injuries here on Earth could also result.
In many areas of microgravity research, says Eugene Trinh, director of the physical sciences division of NASA’s Office of Biological and Physical Research, "our scientific understanding is far from complete. A long-term basic research platform in space will help us make the next quantum leaps forward." In the meantime, research will continue aboard the space station and—as with the butterflies—on shuttle missions.
Back in their Georgia classroom after the shuttle launch in late July 1999, the students anxiously watched their experiment unfold on the Internet. The fate of their habitat had been entrusted to Lieut. Col. Eileen Collins, the first woman to command a shuttle mission. NASA ground personnel relayed real-time images of the insects in their clear Lexan box. The larvae, floating and turning in the air, slowly formed chrysalises around themselves. And one by one, from the crusted chrysalises the students had already affixed to the crossbar, emerged three-inch-wide butterflies dappled with pale orange, white, brown and black. Nature had prevailed.
"This museum is dedicated to all explorers of air and space," says Gen. John R. Dailey, director of the National Air and Space Museum, and formerly second in command at NASA. "These butterflies show that young people, not just adults, can be space explorers, contributing to knowledge."
Through its research opportunities and Internet broadcasts, SPACEHAB hopes to expand the S*T*A*R*S program to reach hundreds of thousands—if not millions—of students around the world. Next April, six more student experiments will fly aboard the shuttle, including a silkworm experiment designed by Chinese students. Already, this past March, a S*T*A*R*S experiment—involving teams of students from around the world—was begun on Zvezda, an all-purpose Russian module on the space station.
Kimberly Campbell, S*T*A*R*S’ program manager, believes the main benefit of the student programs will be kindling enthusiasm for space, science and engineering. "It challenges young minds to ask 'Why?' and provides the tools necessary to discover the answers on their own."
by Julie Wakefield