Artificial Gravity 101

Why Gravity Matters (Again)

In orbit, astronauts experience microgravity, which sounds peaceful until you look at what it does to the human body: bone loss, muscle atrophy, fluid shifts, vision changes, and more. For space biology and materials research, gravity, or the lack of it, affects nearly everything.

To go further into space, stay longer, and study more, we need better ways to work with gravity, not without it.

What Is Artificial Gravity?

Artificial gravity is the creation of a gravity-like force through acceleration, most commonly centrifugal force.

When you rotate something, like a space station, a lab module, or a bucket with a phone in it, you generate a force that feels like gravity. This force pushes things toward the outer edge of the rotation, just like real gravity pulls us toward the ground.

The formula: $
a = \omega^2 r $

Where:

$\ a $ is acceleration (aka “artificial gravity”)
$\ \omega $ is angular velocity (spin speed)
$\ r $ is radius from the center point mass

How Can You Create It?

You have two main ways:

Rotational systems: Spin a ring, a habitat, or even a small capsule to generate centrifugal force.
Linear acceleration: Constant forward motion creates G-forces, but it’s not practical for long-term living or science research as if you’re accelerating somewhere, you’ll eventually get there.

Rotational systems are the most accessible for research and implementation.

Centrifugal Force: Friend or Foe?

While artificial gravity is promising, it’s not perfect:

Coriolis effects (when you move your head inside a spinning station) can cause nausea
Gravity gradients (if your head is at 0.9G, your feet at 1G) may create unexpected biological responses
Energy cost and mechanical complexity increase with larger radius and speed

Still, it’s the most viable path we have to creating controlled gravity environments in space.

Why the ISS Doesn’t Use It

The ISS was never designed with artificial gravity in mind.

Reasons:

Rotating a massive structure adds complex momentum challenges
Requires a split design (gravity and zero-G modules)
Adds risk to a system optimized for microgravity research

Instead, the ISS uses restraint systems, exercise equipment, and countermeasures to deal with humans in microgravity, but it still doesn’t solve the long-term effects.

How Spark Gravity Fits In

At Spark Gravity, we’re exploring how to build modular, programmable gravity platforms.

We’re starting small: our first experiment involves a phone in a bucket spinning at 1.5–2G.

But it’s a stepping stone to reusable artificial gravity modules on Earth and in orbit.

Artificial gravity lets us tune gravity as a variable, not just a constraint. That unlocks new forms of biotech, materials science, and human space habitation.