MMS Vehicles

by Cody Evans

Launch Vehicle

The hardest part of space travel is getting into space. The Earth has an enormous gravitational pull, and a spacecraft must reach a speed of 17,500mph to break the gravitational pull. The MMS satellites do not have the power needed to get into orbit. NASA will solve this problem by launching the four MMS spacecraft on an Atlas V rocket.
Atlas V launch (14 MB)

Since its inaugural flight on August 21, 2002, NASA has used the Atlas V rocket to launch eight satellites into space. Created by Lockheed Martin, the Atlas rocket was originally used as a weapon in the Cold War. However, Lockheed Martin quickly adapted it for space transportation. The Atlas V uses the Russian made RD-180 rocket engine and the new Common Core Booster to launch itself into space. Also, the Atlas V can have up to five strap-on Solid Rocket Boosters for extra power.
The second stage of the rocket is powered by either one or two Pratt & Whitney RL10A-4-2 rocket engines. The four satellites will be held in the upper portion of the spacecraft, called the clam shell. More than likely, the four spacecraft will be stacked on top of one another. To reduce vibration, NASA will not use the strap-on rocket boosters. Depending on engine configuration and payload size, Atlas V rockets have different designations:
To find out more about Atlas V rockets, click here



MMS Spacecraft

The MMS mission calls for four identical spacecraft in order to gather the measurements needed by NASA. Each spacecraft will have identical scientific payloads. The MMS spacecraft were designed for simplicity and ease of packaging to simplify launch procedures. The MMS spacecraft are flat octagons, with their center of gravity in the center of the spacecraft. This is done so they won’t tip over in the clam-shell during launch.
Also, the spacecraft has a cylinder structure in the center of the octagon. When stacked on top of each other, this forms a very strong structure capable of withstanding the shock of blastoff. The spacecraft are powered by the suns’ energy. Eight solar array panels allow the spacecraft to capture the suns’ energy. The spacecraft have a very “open” configuration which allows easy access to instruments inside the spacecraft.

Spacecraft stacked in clam-shell
Spacecraft formation


The spacecraft will travel in a tetrahedral formation to gather 3-dimensional information. The interspacecraft distances will range from ten kilometers to tens of thousands of kilometers. To keep formation, the spacecraft have special sensors called Interspacecraft Ranging and Alarm System (IRAS). Basically, the spacecraft use radio waves to detect their distance from each other. To communicate with Earth, each spacecraft is equipped with an X-band frequency radio.

Pictures taken from NASA website