wired | Every spacecraft that has ever left Earth has relied on some type of
propellant to get it to its destination. Typically a spacecraft moves by
igniting its fuel in a combustion chamber and expelling hot gases.
(Even more exotic forms of propulsion, such as ion thrusters, still
require propellant.) That’s why humans have remained stuck so close to home.
A spacecraft can only accelerate as long as it has fuel to burn or a
planet to loop around for a gravitational assist. Those methods can’t
even carry a vehicle all the way to Alpha Centauri, our closest
neighbor, in any reasonable amount of time. The fastest spacecraft ever
built, the Parker Solar Probe, which will hit speeds over 400,000 miles
per hour, would take thousands of years to get there.
Woodward’s
MEGA drive is different. Instead of propellant, it relies on
electricity, which in space would come from solar panels or a nuclear
reactor. His insight was to use a stack of piezoelectric crystals and
some controversial—but he believes plausible—physics to generate thrust.
The stack of crystals, which store tiny amounts of energy, vibrates
tens of thousands of times per second when zapped with electric current.
Some of the vibrational frequencies harmonize as they roll through the
device, and when the oscillations sync up in just the right way, the
small drive lurches forward.
This
might not sound like the secret to interstellar travel, but if that
small lurch can be sustained, a spacecraft could theoretically produce
thrust for as long as it had electric power. It wouldn’t accelerate
quickly, but it could accelerate for a long time, gradually gaining in
velocity until it was whipping its way across the galaxy. An onboard
nuclear reactor could supply it with electric power for decades, long
enough for an array of MEGA drives to reach velocities approaching the
speed of light. If Woodward’s device works, it’d be the first propulsion
system that could conceivably reach another solar system within the
lifespan of an astronaut. How does it work? Ask Woodward and he’ll tell
you his gizmo has merely tapped into the fabric of the universe and
hitched a ride on gravity itself.
Sound impossible? A lot of theoretical physicists think so too. In fact, Woodward is certain most
theoretical physicists think his propellantless thruster is nonsense.
But in June, after two decades of halting progress, Woodward and Fearn
made a minor change to the configuration of the thruster. Suddenly, the
MEGA drive leapt to life. For the first time, Woodward seemed to have
undeniable evidence that his impossible engine really worked. Then the
pandemic hit.
On a clear night in March 1967, Woodward was stargazing on the rooftop
of PensiĆ³n Santa Cruz, a hotel in the heart of Seville, in Spain. The
26-year-old physicist was struggling with his chosen profession and had
taken a break from graduate work at New York University. He found
himself drawn to fringe research topics, particularly those having to do
with gravity, which he knew would make it hard to get a job. “It became
clear to me simply by looking at the physics department around me that a
bunch of people like that were unlikely to hire someone like me,”
Woodward says. So he decided to try something else. He had picked up
flamenco guitar as an undergrad and even performed in clubs in New York.
Inspired by his aunt, a CIA officer who had learned to play the
instrument while stationed in Madrid, he headed to Spain to pursue a
career in it.
At the time, the space race was only a decade old and satellite
spotting was a popular sport. As Woodward gazed up from atop his Spanish
hotel, he saw a speck of light arcing across the sky and mentally
calculated its path. But as he watched the satellite, it began deviating
from its expected trajectory—first by a little and then by a lot.
Everything
Woodward knew about satellites told him that what he was seeing should
be impossible. It would take too much energy for a satellite to change
its orbit like that, and most satellites weren’t able to shift more than
a couple of degrees. And yet, he had just seen a satellite double back
with his own eyes. He didn't conclude that engineers at NASA or in the
Soviet Union must have secretly achieved a breakthrough in satellite
propulsion. Instead, he believes he saw a spacecraft of extraterrestrial
origin. “Critters at least as clever as us had figured out how to get
around spacetime far better than we are capable of doing,” Woodward
says. That changed the question, he says, from if it was possible to how.
Never
one to doubt the power of the human intellect, especially his own,
Woodward reckoned he could build a similar interstellar propulsion
system if he put his mind to it. “If somebody figured out how the hell
to do something like that, they probably aren’t an awful lot smarter
than I am,” Woodward recalls thinking at the time. “So I thought maybe I
should devote a little time to trying to do that.” It was a project
that would occupy him for the rest of his life.
Woodward completed
his master’s degree in physics at NYU in 1969, and he left to do a PhD
in history at the University of Denver shortly after. His decision to
pivot from physics to history was a pragmatic one. As a master’s
student, he spent a lot of his time combing through old scientific
journals in search of promising gravitational research that had been
abandoned or hit a dead end so he could pick up the torch. “I was doing
the history of science already, so I might as well get a degree in it,”
Woodward says. “It was an obvious thing to do.” As an academic
historian, he’d enjoy the job security that comes with uncontroversial
research and still have the freedom to study fringe gravitational topics
as an avocation. He accepted a position in the Cal State Fullerton
history department in 1972.
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