A U.S. intelligence agency document proposed an almost unimaginable idea: a tiny, impossibly heavy sphere whose gravity would cancel out Earth’s pull in the area beneath it.
The sphere was never built, and there is no practical way to create one today. Still, the idea appeared in an intelligence report exploring possible ways to control gravity, including to make it easier for aircraft and rockets to take off.
A Tiny Sphere With an Unimaginable Mass
Written in 2010, the report surveyed theoretical ideas for using gravity in aviation and spaceflight. It did not present original research or a working device. The report was one of a series prepared as part of a broader U.S. intelligence agency program. Not every document in the program dealt directly with aircraft or future threats.
One of the ideas in the report came from a researcher named Forward. He proposed using material that packed an enormous amount of matter into a tiny volume. The sphere in his example would have been about 32 centimeters in diameter, yet weighed four million metric tons.
Two Gravitational Pulls, Canceling Each Other Out
Under the proposal, the sphere would generate its own gravity. Suspended above the ground, it would pull objects upward while Earth pulled them downward. In the space between the sphere and the ground, the two forces might balance out.
Instead of falling to the ground or being pulled toward the sphere, an object in that area would not accelerate toward either one. The report imagined this as a way to keep things aloft and perhaps make it easier for aircraft to take off without fighting Earth’s gravity as much.
What Remains Unknown
The report does not explain how to create the necessary material or control such a sphere. It describes engineering challenges that cannot currently be overcome in practice and notes that using the idea to propel aircraft falls outside the accepted understanding of physics.
A basketball-sized sphere weighing four million metric tons. For now, it exists only as an idea in a report.
