Luke Skywalker’s landspeeder in “Star Wars: A New Hope” didn’t sell for much — just 2,000 credits thanks to a newer model on the market — but it captured the interest of science fiction fans everywhere. Speeder bikes featured during the “Return of the Jedi” chase scene on Endor only upped the ante: What would it be like to use this type of hover technology to discover the joy of flying? Sure, it’s no Millennium Falcon, but it’s a good start.
With May the 4th — “Star Wars” Day — just around the corner, it’s worth taking a look at hover tech: Our obsession with the idea, what’s currently on the market and what the science says about “real” anti-gravity options.
Floating on Air
Humanity’s interest in hovering vehicles started long before Luke swung a lightsaber. As noted by the BBC, the first hovercraft was developed by Sir Christopher Cockerell in 1959. It used a cushion of air to hover just above ground or water and avoid the common pitfalls of uneven surfaces. Until October 2000, hovercraft were used to ferry people and cars across the English Channel when competition from the Channel Tunnel and traditional ferry boats made the service obsolete. According to Popular Mechanics, commercial hovercraft have experienced a sharp decline from their heyday in the 1970s due to large fuel and maintenance costs combined with a lack of creature comforts.
The landspeeder is a solid hovercraft analog: Both are slightly unwieldy and keep a low profile relative to the ground. While in the “Star Wars” universe newer models supplanted Luke’s X-34, our version of slow-speed, low-riding hovercraft are largely confined to the footnotes of history.
What about speeder bikes? These motorcycle-like danger sticks were seen whizzing at top speed through the forests of Endor — and were responsible for more than one unexpected stormtrooper–tree trunk collision. Fast and agile, repulsorlift-driven jumpspeeders offered an inherent “wow” factor, inherent awesomeness and (hopefully) hazard pay for Empire employees.
While we haven’t created anything quite so cool, companies are starting to roll out “hoverbikes” that do a decent speeder impression. As noted by Science Alert, it’s now possible to preorder an FAA-approved hoverbike for $150,000. Using four battery-powered rotor blades, the bike can reach speeds of 60 miles per hour and heights of 16 feet. A single charge nets between 10-25 minutes of flying time if the weather cooperates. Strong winds — and rider weight — also impact flight time.
Put simply, this nails two out of three: The bike hovers just like the ones in the movies and can zip along at breakneck speeds. The problem? Battery life. The chase scene on Endor would have been far less exciting if the Empire had to find charging stations every half an hour to keep up their search for the rebels. This may be a temporary setback, however — as noted by Nature, new research on potassium-air batteries with organic anodes could pave the way for significant storage increases.
Coming Back Down to Earth
It’s one thing to mimic “Star Wars” hover technology; it’s another to actually create vehicles using repulsor-type solutions. The concept isn’t new to science fiction: Other big franchises such as “Star Trek” regularly use anti-gravity tech to solve problems. But is it actually feasible to create repulsive force rather than simply blowing ever-larger volumes of air at the ground?
According to a recent Forbes piece, probably not. Why? Because unlike electric force — which has both positive and negative charges — gravitational force has only one charge governed by mass and energy: Attractive. As a result, it’s not possible to create a “gravitational conductor” which would effectively trap gravity outside and set up a gravity-free area inside. For that to happen, we’d need negative gravitation mass, or anti-mass, which would fall up instead of down when exposed to gravitational forces.
Although theories using anti-mass exist, such as the Alcubierre solution for warping space-time, scientists haven’t discovered any evidence that anti-mass exists. One potential candidate is anti-matter, but even though anti-matter particles have been observed to have electric charges and spin opposite their normal-mass counterparts, their interaction with gravity should be the same as normal mass: They should fall down.
If scientists do manage to discover a naturally-occurring source of anti-mass or create an artificial version, it then becomes possible to create both small- and large-scale gravitational conductors and capacitors. In space, this means giving ships and stations their own gravity fields independent of the surrounding mass. On Earth, it means equipping hovercraft and hoverbikes with the repulsive technology necessary to circumvent the law of gravity and provide a truly authentic “Star Wars” experience.