Multi-mission Modular Spacecraft, also known as the MMS, was originally designed by NASA to serve the largest array of functions for the space program possible to decrease the cost of space missions. It was designed to operate in four distinct areas of missions. The MMS began development about a decade before it became implemented in the 1980s and 1990s. The basic MMS was made up of three different modules. They include the altitude control, communications and data handling, and the power subsystems. The idea of a modular system serving many purposes was the pioneer of the leading systems within the space technology ecosystem today as it has left a lasting legacy. The MMS was intended to be "Shuttle compatible", i.e. recoverable/serviceable by the

Space Shuttle orbiter The Space Shuttle orbiter is the spaceplane component of the Space Shuttle, a partially reusable orbital spacecraft system that was part of the discontinued Space Shuttle program. Operated from 1977 to 2011 by NASA, the U.S. space agency, thi ...

Missions

NASA's_Upper_Atmosphere_Research_Satellite

It was used for: *

Solar Maximum Mission The Solar Maximum Mission satellite (or SolarMax) was designed to investigate Solar phenomena, particularly solar flares. It was launched on February 14, 1980. The SMM was the first satellite based on the Multimission Modular Spacecraft bus m ...

(SMM), 1980 *

Landsat 4 Landsat 4 is the fourth satellite of the Landsat program. It was launched on July 16, 1982, with the primary goal of providing a global archive of satellite imagery. Although the Landsat Program is managed by NASA, data from Landsat 4 was coll ...

, 1982 * Landsat 5, 1984 * Upper Atmosphere Research Satellite (UARS), 1991 * Extreme Ultraviolet Explorer (EUVE), 1992 *

TOPEX/Poseidon TOPEX/Poseidon was a joint satellite altimeter mission between NASA, the U.S. space agency; and CNES, the French space agency, to map ocean surface topography. Launched on August 10, 1992, it was the first major oceanographic research satellite. ...

, 1992 TOPEX/Poseidon: Perspectives on an Ocean Planet - MMS
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Development

Before the MMS was the standardized space ship system, they began studying how to make a cost effective method of

Space exploration Space exploration is the use of astronomy and space technology to explore outer space. While the exploration of space is carried out mainly by astronomers with telescopes, its physical exploration though is conducted both by uncrewed robo ...

. To achieve lower cost space travel, NASA's approached the idea with a production line mentality, to have inherited parts in as many aspects of the rocket as possible to allow fast production. The first idea was to use existing spacecraft designs, but with slight modifications. The main issue was designing a computer that could service any mission with slight modifications to the mission. To do this, they developed a computer for the MMS that could service variance types of missions within the solar system such as: solar, stellar, and earth missions. By designing this space computer to be easily changed, instead of building a new computer with all new hardware every mission, they only had to make

software Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work. At the lowest programming level, executable code consist ...

changes. This design greatly reduced cost when developing new spacecraft.

Modules

What made MMS so effective was the adaptability of the spacecraft to be able to conduct missions in a multitude of areas. The MMS was designed using multiple modules that made this possible. The modules include ACS Module, Power Module, Small Impulse Propulsion Module, Large Impulse Propulsion Module, C & CH Module, and Module support structure. This system allows for interchangeable software and hardware, and ultimately allows it to be repaired to be used at a lower cost level.

References

NASA satellites Spacecraft components Spacecraft design {{Spacecraft-stub