Introduction & Importance

Satellite Refueling

There are over 11,913 active satellites in orbit, many of which run out of fuel long before their hardware fails. When that happens, they become radioactive space junk, even if thier parts still functional[1]. Satellite refueling solves this problem by allowing satellites to top up their fuel in orbit, extending their missions by years and reducing waste. Enabling for easier, cheaper and faster space exploration[2].

Space debris and satellites orbiting Earth

Key Stats

3–5 kg

Enough to fill small satellites tanks!

600–830 km

Typical altitude of refuelable satellites

$500M

Cost of losing a high-end satellite due to fuel run out

5–10 more years

Mission life extension via refueling[3]

Fueling Process

1

Refueling spacecraft launches

2

It approaches the satellite

3

Docks at standard fill/drain valve

4

Transfers hydrazine propellant

5

Departs → satellite continues mission

Satellite docking with robotic arms
How It Works

The Technology Behind Satellite Refueling

Refueling spacecraft are equipped to find and dock with satellites in low Earth orbit (LEO). These vehicles use robotic arms or magnetic docking to connect with a standard refueling valve [4]. Once latched, they transfer hydrazine (fuel used in most satellite thrusters) through a safe, controlled system [5]. The entire operation is autonomous (self-operated) [6]. After refueling, the refueling spacecraft detaches and moves to its next target [7].

Fact Box

Fuel type: Hydrazine
Method: Docking at fill/drain valve
Current tech: Blue Canyon Technologies X-Sat bus, Orbit Fab's RAFTI port
Challenges: Orbital alignment, valve compatibility, robotic precision
Satellite refueling operation
Companies & Future Outlook

The Future of Space Logistics

In-space refueling is still a new field, but its impact is growing rapidly. From national agencies to private startups, companies are racing to make fuel delivery in space reliable and routine [8]. As satellites become more modular and servicing more accessible, refueling may become a standard step in mission design[9] just like plugging in your car.

Who's Doing It

  • •
    Orbit Fab – Developing RAFTI refueling port and "gas stations in space"
  • •
    Northrop Grumman – Mission Extension Vehicle (MEV) extended life of Intelsat satellites
  • •
    NASA OSAM-1 (cancelled) – Originally planned to refuel and upgrade a Landsat satellite
Orbit Fab's gas station in space
Think Orbital satellite servicing

Why It Matters

Reduces space debris

Saves billions in satellite replacement

Enables commercial servicing economy

Opens door to long-term human missions (Moon, Mars)

Satellite servicing mission