Space logistics

Space logistics is "the theory and practice of driving space system design for operability, and of managing the flow of material, services, and information needed throughout a space system lifecycle," and includes terrestrial logistics in support of space travel, including any additional "design and development, acquisition, storage, movement, distribution, maintenance, evacuation, and disposition of space materiel", movement of people in space (both routine and for medical and other emergencies), and contracting and supplying any required support services for maintaining space travel.
History.
As early as 1960, Wernher von Braun spoke of the necessity and the underdevelopment of space logistics:
We have a logistics problem coming up in space ... that will challenge the thinking of the most visionary logistics engineers. As you know, we are currently investigating three regions of space: near-Earth, the lunar region, and the planets. While it is safe to say that all of us have undoubtedly been aware of many or most of the logistics requirements and problems in the discussion, at least in a general way, I think it is also safe to state that many of us have not realized the enormous scope of the tasks performed in the logistics area. I hope the discussions bring about a better understanding of the fact that logistics support is a major portion of most large development projects. Logistics support, in fact, is a major cause of the success or failure of many undertakings.
By 2004, with NASA beginning a governmental initiative to explore the Moon, Mars, and beyond, a number of deficiencies in both capacity and capability to support logistics needs even in low-Earth orbit had been identified.
By 2005, analysts recognized the coming opportunity for the national governments involved with the Space Shuttle program to reduce costs by acquiring cargo transportation logistics services commercially following completion of the construction phase of the International Space Station, then expected by 2010.
Activities after 2005.
According to Manufacturing Business Technology,
Examples of supply classes.
Among the supply classes identified by the MIT Space Logistics Center:
In the category of space transportation for ISS Support, one might list:
Tianzhou (spacecraft) is the only expendable unmanned resupply spacecraft to Chinese Space Station.
State of the ISS logistics capability in 2005.
A snapshot of the logistics of a single space facility, the International Space Station, was provided in 2005 via a comprehensive study done by James Baker and Frank Eichstadt. This article section makes extensive reference to that study.
ISS cargo requirements.
, the United States Space Shuttle, the Russian Progress, and to a very limited extent, the Russian Soyuz vehicles were the only space transport systems capable of transporting ISS cargo.
However, in 2004, it was already anticipated that the European Automated Transfer Vehicle (ATV) and Japanese H-IIA Transfer Vehicle (HTV) would be introduced into service before the end of ISS Assembly. As of 2004, the US Shuttle transported the majority of the pressurized and unpressurized cargo and provides virtually all of the recoverable down mass capability (the capability of non-destructive reentry of cargo).
Cargo vehicle capabilities.
Baker and Eichstadt also wrote, in 2005:
Commercial opportunity.
Baker and Eichstadt also wrote, in 2005:
Rack transfer capability.
Baker and Eichstadt also wrote, in 2005:
Recoverable reentry–pressurized payloads.
Baker and Eichstadt also wrote, in 2005:
Mixed manifest capability.
Baker and Eichstadt also wrote, in 2005:
Propellant transfer.
Baker and Eichstadt also wrote, in 2005:
Downmass.
While significant focus of space logistics is on upmass, or payload mass carried up to orbit from Earth, space station operations also have significant downmass requirements. 
Returning cargo from low-Earth orbit to Earth is known as transporting "downmass", the total logistics payload mass that is returned from space to the surface of the Earth for subsequent use or analysis.
Downmass logistics are important aspects of research and manufacturing work that occurs in orbital space facilities. In the 2020s, the term began to also be used in the context of mass movement to and from other planetary bodies. For example, "the upmass and downmass capacity [of the SpaceX Starship HLS lunar lander] far exceeded NASA’s requirements"
For the International Space Station, there have been periods of time when downmass capability was severely restricted. For example, for approximately ten months from the time of the retirement of the Space Shuttle following the STS-135 mission in July 2011—and the resultant loss of the Space Shuttle's ability to return payload mass—an increasing concern became returning downmass cargo from low-Earth orbit to Earth for subsequent use or analysis.
During this period of time, of the four space vehicles capable of reaching and delivering cargo to the International Space Station, only the Russian Soyuz vehicle could return even a very small cargo payload to Earth. The Soyuz cargo downmass capability was limited as the entire space capsule was filled to capacity with the three ISS crew members who return on each Soyuz return. At the time none of the remaining cargo resupply vehicles — the Russian Space Agency Progress, the European Space Agency (ESA) ATV, the Japan Aerospace Exploration Agency (JAXA) HTV — could return any downmass cargo for terrestrial use or examination.
After 2012, with the successful berthing of the commercially contracted SpaceX Dragon during the Dragon C2+ mission in May 2012, and the initiation of operational cargo flights in October 2012, downmass capability from the ISS is now per Dragon flight, a service that is provided by the Dragon cargo capsule routinely. A return capsule tested in 2018 called the HTV Small Re-entry Capsule (HSRC) could be used in future HTV flights. The HSRC has a maximum downmass capability of .