National Aeronautics and CRYOGENIC Space Administration

FLUID MANAGEMENT

WHAT’S CRYOGENIC FLUID 

MANAGEMENT?

Cryogenic Fluid Management (CFM) 

is a term used to describe a suite of 

technologies that store, transfer, and 

measure ultra-cold fluids—such as liquid 

hydrogen, liquid oxygen, and liquid 

methane. These cryogens are the most 

common propellants in use in space 

exploration, making cryogenic fluid 

technologies integral to NASA’s future 

exploration and science efforts.

NASA’s vision for space exploration 

and science requires high-performance 

chemical, electric, and nuclear propulsion 

solutions. The agency will use cryogens 

for Earth-to-orbit transportation, human 

missions to the Moon and Mars, planetary 

exploration, and in-situ resource utilization 

(ISRU) production—all of which will require 

propellant depots on the surface and 

in space to refuel those cryogenic 

propellant systems.

While critical for today’s space flight 

vehicles, traditional chemical propellants 

are not ideal for missions to deep space. 

The performance required for NASA’s 

boldest missions to the Moon 

and Mars will require 

the use of cryogens as 

a propulsive solution. 

Beyond exploration 

missions, NASA 

will continue to use 

cryogenics to enable 

infrared and X-ray 

astronomy, biological sciences, and 

fundamental investigations into the

origins of our universe.

What makes cryogenic fluid storage 

challenging is a continual loss of cryogens 

over time due to their propensity to boil 

off at warmer temperatures. Through a 

multilayer insulation, the amount of loss

can be controlled for short periods of time, 

thus minimizing the loss of propellant.

This passive control measure alone 

will not prevent the loss of cryogens.

With cryocoolers to actively control 

heat — similar to how a refrigerator 

functions — from going into the propellants, 

little to no propellant is lost. The result is 

what’s commonly referred to as a “zeroboiloff system,” which eliminates the need 

for oversized tanks and extra propellant; 

both add weight and require the launch 

vehicle to burn more propellant.

Each kilogram of propellant mass saved 

means more payload mass can be carried 

to deep space, which is critical to the 

success of NASA’s Artemis deep

space missions.
WHY IT’S IMPORTANT?

NASA explores the unknown in air and 

space, solving mysteries of Earth, 

the solar system, and beyond. 

For the agency to achieve its Moon 

to Mars goals, it needs cryogenic 

technology to keep hydrogen and 

other fluids cold for long periods of time 

while in deep space. This is critical to 

preventing boil off and ensuring the 

cryogens remain in usable condition. 

Venting or active cooling must be 

utilized to prevent over-pressurization 

in propellant tanks. Venting propellant 

in zero-gravity environments is likely 

to cause unacceptable losses of 

propellant. Certain long-term space 

cryogenic storage technologies have 

been developed mainly for thermal 

management of scientific instruments for 

telescopes and other applications.

These developments have not been 

applied to cryogenic propellant storage 

at the scale needed for the Mars 

architecture. Other CFM technologies 

that would ensure safe, reliable cryogenic 

storage and supply to the propulsion 

systems include low-leakage valves, 

liquid acquisition and transfer, and mass 

gauging.

The agency will use the knowledge and 

experience it has gained from the Moon 

and during operations in low-Earth 

orbit to prepare for humanity’s next 

giant leap — sending astronauts to Mars. 

It all starts with U.S. companies delivering 

scientific instruments and technology 

demonstrations to the lunar surface. 

NASA will then land the first woman 

and first person of color on the Moon 

under Artemis, establishing sustainable 

exploration and science efforts there by 

the end of the decade, including a small 

lunar space station called the Gateway.

These long-duration missions require 

cryogenic fuel that will power exploration 

for the benefit of all. Developing 

architecture on the Moon and Mars to 

enable explorers to go — and stay — 

 requires safe storage of propellants.
CFM OBJECTIVES

• Mature CFM technologies vital to

NASA’s future missions in science and

exploration, which utilize both chemical

and nuclear in-space propulsion, landers,

and in-situ resource utilization

• Increase CFM technology readiness and

integrate into a large, system-level flight

demonstration

• Enable industry demonstrations of their

respective CFM technologies developed

under NASA’s Tipping Point contracts,

which are milestone-based, firm fixedprice contracts

STRATEGY

NASA and American industry have 

developed and tested numerous 

technologies to enable long-term CFM, 

which are essential for establishing a 

sustainable presence on the Moon and 

for enabling future crewed missions to 

Mars. Implementation of the Tipping Point 

technologies will require in-space flight 

demonstrations to advance CFM and 

help the agency and its partners better 

understand low-gravity fluid behavior. 

Further technology development will forge 

a path to a larger CFM demonstration 

mission in the early 2030s with some 

version of high-capacity active cooling and 

fluid transfer.

WHAT’S AHEAD

CFM technology development and 

demonstration is a significant emphasis 

area for NASA’s Space Technology Mission 

Directorate (STMD). STMD is focused on 

developing key areas required for longterm cryogenic propellant in-space storage 

and transfer. NASA is performing extensive 

technology maturation and risk reduction 

for key CFM technologies, laying the 

groundwork for a system-level spaceflight 

demonstration that integrates major CFM 

technologies prior to mission infusion for 

cryogenic propulsion stages.

The Cryogenic Fluid Management 

portfolio is led by NASA’s Marshall Space 

Center in Huntsville, Alabama, and Glenn 

Research Center in Cleveland, Ohio. This 

work is managed by NASA’s Technology 

Demonstration Missions (TDM) Program, 

part of NASA’s Space Technology Mission 

Directorate, which oversees a portfolio of 

technology demonstration projects across 

NASA centers and American industry 

partners.

Learn more about CFM.

National Aeronautics and Space Administration

George C. Marshall Space Flight Center

Huntsville, AL 35813

www.nasa.gov/marshall/

www.nasa.gov

FS-2023-078-133-MSFC MSFC G–641961