A University of Tennessee Space Institute professor recently challenged a group of Vermont high school students to think, study, work hard, and help find unique answers for mankind’s energy needs.
“Use your brains, be willing to work, be motivated as to where you’re going, and don’t let anybody tell you it can’t be done,” Gary A. Flandro said in a two-way teleconference with Bill Muench’s “Space and Time Class” at the Burr and Burton Academy in Manchester, Vt.”
Flandro, who occupies UTSI’s Boling Chair of Excellence in Space Propulsion, discussed potential abundant energy sources “60 miles above our heads,” explained the “gravity assist” method that he applied in charting Voyager’s “grand tour of the planets,” and declared that the answer “to all our energy needs far into the future” can be found on the moon “if we can figure out how to collect it and get it back to the earth.”
He was referring to the moon’s “abundant supply” of Helium 3, which he said is a key to fusion energy. He talked about possible ways to travel in space other than by expensive rocket-propelled vehicles, including developing “space elevators” powered by electricity. He also mentioned solar, or “light” sails as a potential way to capture solar energy through thrust created by the reflection of solar radiation from the mirror-like surface. (Flandro and others have explored the potential of using solar sails as sources of energy to use in the manned exploration of Mars.)
Acknowledging that the supply of fossil fuels is shrinking on Earth’s surface, the speaker said, “Our entire transportation system, once based on coal, is now based on oil,” and he urged the youths to “think outward.” He suggested that the earth is not a closed environment that stops at the edge of the atmosphere, saying, “We can leave its surface and seek energy sources outside.” He reminded the students that “plants are the most effective gadgets to collect energy from the sun.”
It is this energy that eventually produces the petroleum sources that we depend on as plants decay and the material collects over millions of years, he said..
“All energy that we use comes from the sun, although indirectly,” Flandro declared. “We’ve got to figure out a way to get energy efficiently directly from the sun by collecting it in orbit and moving it to the surface in a form we can utilize.”
During the hour and a half session, several students asked questions or responded to those asked by the professor. After Flandro explained the “gravity assist” theory, one student asked how he accomplished all the calculations involved in the Voyager mission.
“Not with a big complicated computer,” Flandro answered. “Computers that you use now are 100 times more powerful than those we had. I did most of the calculations with a slide rule – you probably don’t know what that is. Hand calculators had not been invented and were thought to be an “impossible” development for the distant future. Nevertheless, the slide rule predictions proved to be almost totally accurate. I nailed the launch dates and flight times, and the trajectories flown in the actual Voyager missions were just as the approximate methods I used predicted. You don’t have to have big computers. Use your heads.”
As a graduate student at Caltech, Flandro worked summers at the Jet Propulsion Lab where he was asked to find ways to accomplish unmanned exploration of the outer planets such as Jupiter, Saturn, Uranus, and Neptune.
Flandro remembers hearing that many scientists at JPL felt that such exploration would be impossible due to the long flight times and enormous propulsive energy requirements. In other words, he says, he was told that such flights were “impossible.” In closing remarks to the Vermont class, he quoted Sir Arthur C. Clarke, noted science fiction writer who also is credited as the inventor of the communication satellite, that “when a respected person tells you that something is possible, he is probably right, but if he tells you that something is impossible, he is probably wrong.” Remembering what is known as “Clarke’s law,” Flandro said he proceeded to find the necessary techniques that led to the successful Voyager mission.
This is the second year in a row that Flandro has interacted with Muench’s class using the Institute’s distance learning video classroom. It is an example of a growing effort by various professors at UTSI to encourage interest in science and engineering. He said he would welcome an opportunity to schedule similar sessions in area high schools.
Gary Flandro looks at the monitor while addressing a Vermont class of high-schoolers (right) from UTSI’s Distance Learning video classroom.