Published in the February 17 – March 1, 2016 issue of Morgan Hill Life
By Marty Cheek
Marty Cheek, publisher Morgan Hill Life
On my first day of class as a student reporter on the Gavilan Rambler, I walked into the Gavilan College newspaper room in a lighthearted mood. A radio played a KCBS news report in the background. Oblivious of the serious tone of the broadcast, I sat down at a table across from a young woman. Tears streamed down her face. I asked if she was OK.
“The Challenger exploded,” she said.
The date was Jan. 28, 1986. At 11:39 a.m. Florida time, Americans watched on live TV the image of the space shuttle Challenger lifting off in a pillar of white exhaust. Hardly a minute into the flight, the shuttle exploded in a ball of flame. The seven crew members were killed, including Christa McAuliffe, a high school teacher from Concord, N.H. She had won a nationwide contest to join the Challenger mission — and young students in classrooms around the country were watching the shuttle liftoff with the first teacher in space. Later, a commission determined the cause of the accident was a failed O-ring seal that allowed a stream of hot gas to ignite an external fuel tank.
Considering the last 30 years since Challenger, the world has continued its progress in lifting people and payloads into Earth orbit. But the use of rockets to take trips into space is still a risky and expensive enterprise. Five years ago, the space shuttle program was retired because it never met its promise for a low-cost access into orbit because of reuse-ability.
NASA is working on building its new Space Launch System rocket for possible journeys to Mars. Entrepreneurs including Elon Musk of Tesla, Jeff Bezos of Amazon, and Richard Branson of the Virgin Group have been endeavoring to open up space on a commercial basis. The 21st century is witnessing the pioneering stages of the private space industry. This is an exciting time which may open up Earth orbit to tourism, manufacture and other uses.
The main problem with space trips right now is the cost. The price-tag for just one pound of payload to go into space for the first 100 miles is $10,000. It’s an expensive proposition to burn hundreds of tons of fuel in a few minutes to use Isaac Newton’s basic principles to lift many tons of mass into space.
There is, however, a potential way to significantly reduce the cost and high risk factors of space travel launches.
In recent years with research on a material called carbon nanotubes, scientists have found an extremely lightweight but super strong material that might one day be used to build a ribbon-like cable stretching from the surface of our planet up to a space station several thousand miles in Earth orbit. Capsules holding people and equipment could travel up this “space elevator” at a cost of at least one-fortieth the price per pound of a rocket trip.
I was in high school when I first became acquainted with the idea of a space elevator while reading the science fiction novel “The Fountains of Paradise” by Arthur C. Clarke. The author’s story of how human beings designed and built an elevator traveling into geostationary orbit seemed wildly innovative. At that time in the mid-1980s, it also seemed an impossibility. But several decades before the Soviet Union’s Sputnik opened the door to the Space Age, the idea of strapping human beings to a potentially dangerous rocket and shooting them into Earth orbit — and even the Moon — seemed as wildly far-fetched.
The inspiration for the idea of a space elevator was the Eiffel Tower. In 1895, Russian scientist Konstantin Tsiolkovsky considered the famous Parisian landmark, which at that time was the tallest man-made object in the world. Could a tower of iron and steel be built that reached into space many miles above, he wondered. The weight of such a massive structure — a modern Tower of Babel — would be tremendous. The surface of the ground would be compressed so much it couldn’t sustain such a tower.
But now, we are on the verge of a materials science revolution that might make possible within the next 20 years the construction of a space elevator. “Carbon nanotubes” are a member of the fullerene structural family — which means that they consist of a molecule of carbon that is in the shape of a hollow sphere, ellipsoid or (most importantly for a space elevator) a tube. The material forms one-atom-thick sheets of carbon called graphene. Graphene is the strongest substance known to science, and is more than 100 times stronger than the strongest steel. It can also conduct electricity, an important consideration in powering the elevator cabins going up and down a space elevator.
The problem with carbon nanotubes right now is that researchers have not yet been able to make it in the vast quantities required for a space elevator cable.
The world’s record in length is about one inch — so obviously we have a long ways to go in producing the thousands of miles of carbon nanotube cable needed to build the world’s first space elevator.
The space elevator would be humankind’s biggest engineering project ever taken. The first elevator will be the most difficult one to build. It would require rockets to lift the material for the elevator to a construction platform located in geostationary orbit. Once that first elevator is built, however, it could be used to lift more carbon nanotube cables into orbit to construct other elevators around the world. A new age in orbital industry and celestial exploration would begin as more space elevators opened the heavens to humanity.
Accelerated innovation in materials science is the key to building a space elevator with a construction completion date in the next few decades. It will take the combined brain power from many scientists around the world to develop systems to make the graphene ribbon at a length and strength capable of an elevator. The good news is, the material carbon is plentiful throughout Earth — including in the atmosphere as the greenhouse gas carbon dioxide.
The science used in the construction of space elevators might help to alleviate climate change. Researchers are now working on ways to pull carbon dioxide out of the air and store it as a solid. Maybe one day a team of scientists can find a way to use solar and wind-produced electricity to pull carbon dioxide out of the atmosphere and convert the carbon into the nanotubes needed to produce the ribbon for the international space elevator project. Using this system, this material could also be used for other industrial uses, helping to pay for the project.
Humanity has a long ways to go to get to that point in material sciences innovation to construct the space elevator — but this engineering marvel is a possibility. Perhaps on the date Jan. 28, 2086, future passengers will take a ride into space on an elevator cable and salute the seven astronauts of the space shuttle Challenger on the centennial anniversary of the tragedy for paving the way as pioneers of human space exploration.
