In space, location isn’t just about distance—it’s about energy.
What Is a Gravity Well?
Think of gravity like a hill you have to climb
A gravity well represents the energy needed to move an object away from a massive body—like Earth or the Moon. The deeper the well, the more energy (and fuel) required to escape it. In practical terms, launching something from Earth’s surface into orbit is like climbing out of a deep canyon, while transferring between orbits is more like switching lanes on a slope.
This matters because fuel doesn’t just have a dollar cost—it has a delta-v cost: the change in velocity required to move between orbits.
Fuel Gets Pricier the Higher You Go
Altitude drives energy cost—and energy drives pricing
Let’s break it down:
- Low Earth Orbit (LEO) is relatively cheap to reach, but still costs thousands of dollars per kilogram launched.
- Geostationary Orbit (GEO) or lunar orbit require much more energy, and fuel delivered there comes at a premium.
- Lagrange points or high lunar altitudes can demand even more specialized routes and propulsion methods.
The result? Fuel at higher altitudes carries a higher price tag because of the effort it takes to get it there.
How This Affects Depot Placement
Put the fuel where the customers need it—but balance the cost of getting it there
Operators must consider both demand and delivery cost when placing orbital depots. For example:
- A depot in LEO is cheap to stock but less useful for lunar or Mars missions.
- A depot in lunar orbit is highly strategic but expensive to replenish.
- A cisLunar depot (e.g., at Earth-Moon L1) offers balance, acting as a mid-point for interplanetary traffic.
Depot placement becomes a game of logistics, economics, and orbital mechanics.
Pricing Strategy in the Gravity Economy
Why orbital fuel will never have a flat price
In-space fuel pricing will vary by location, supply route, and delta-v cost. Pricing models will likely include:
- Origin-adjusted pricing: Cost includes launch and transfer energy from Earth.
- On-orbit markup: Accounts for depot operations, storage systems, and cryogenic maintenance.
- Route-specific premiums: High-demand or hard-to-reach locations (e.g., lunar south pole) carry service surcharges.
Expect orbital fuel pricing to resemble zone-based shipping costs, scaled to the energy needed for delivery.
Mission Design Depends on Fuel Geography
Fuel availability and price shape how missions are built
The deeper your mission goes into a gravity well, the more planning is required to avoid refueling bottlenecks. That means:
- Designing spacecraft to refuel at multiple points
- Choosing flight paths that minimize energy costs
- Staging assets where fuel is most accessible
Fuel geography becomes mission architecture.
Bottom Line: Altitude Is an Economic Variable
In space, every kilometer upward raises the stakes
The higher you go, the more fuel it takes—and the more that fuel costs. Gravity wells are the invisible force shaping the economics of space. Understanding them is essential for anyone thinking about the business of orbit, from depot placement to satellite servicing to lunar logistics.
In the emerging space economy, the price of access is measured in meters, money, and momentum.
