If you’re an insect with dreams of traveling in outer space, your future is looking bright. Researchers at Japan’s Shizuoka University are this month launching a tiny space elevator on an H-2B rocket from the island of Tanegashima, roughly the size of two matchboxes. Monitoring cameras will watch as the bug-sized compartment attempts to slide up and down a 10-meter cable, suspended in space between two miniature satellites.
The miniature elevator is Japan’s first step toward achieving a much bigger dream: a fully-fledged space elevator, with a lift shaft that shoots 60,000 miles (96,500 kilometers) above sea level, to be used by astronauts and space tourists alike.
Even this rudimentary effort is the result of more than 120 years of wishing, hoping, and dreaming. Konstantin Tsiolkovsky was a Soviet astrophysicist and sci-fi pioneer who predicted manned rockets and self-sustaining space stations years before the age of aviation. In the late 19th century, after visiting the brand new Eiffel Tower in Paris, Tsiolkovsky was struck by the possibility of building literal skyscrapers. His 1895 book, Dreams of Earth and Sky, sets out his vision: A “Tsiolkovsky tower” 22,400 miles (36,000 kilometers) high, with a spindly “beanstalk” leading up to a “celestial castle,” or space station, at the top. You’d take a space elevator to get there, naturally.
In the decades since, scientists have hit a few hurdles in realizing Tsiolkovsky’s dreams. He had envisaged a “compression structure” like the Eiffel Tower, where balanced forces push against one another to keep the building upright. But 1950s researchers could find no building material in existence strong enough to support its own weight at these teetering heights. Instead, in 1959, Russian scientist Yuri Artsutanov proposed running a cable thousands of kilometers long between earth and a geostationary satellite city, complete with greenhouses and observatories.
To keep the tension consistent along the line, the cable would taper out as it rose into the air. Here too, his dreams were stymied by the materials on offer—American researchers in the 1960s determined that the cable would have to be made out of some unknown material at least twice as strong as quartz, diamond, or graphite.
While scientists have tweaked these plans, including suggesting using a captured asteroid as a counterweight, science-fiction writers and futurists unconstrained by mathematical reality have dreamed up a whole flotilla of space elevators. Arthur Clarke’s novel The Fountains of Paradise imagines a 22th-century space elevator rising up from the fictional island of Taprobane. (It’s essentially Sri Lanka, helpfully repositioned closer to the equator.) Clarke’s space elevator is attached with a cable made out of an as-yet undiscovered “pseudo-one-dimensional diamond crystal,” produced in space to defy gravity’s effect on its growth.
Short of moving entire islands, ensnaring asteroids, or growing crystals in space, you might think the space elevator is almost as far-off today as it was for Tsiolkovsky. Not so, says Japan’s Obayashi Corporation, builders of the country’s tallest tower. They want tourists zooming into space by 2050—and are considering other options, in case the Shizuoka university project fails to get off the ground.