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MMS Bookmark and Scale Model Activity

Enjoy this creative ‘Bookmark/Activity’ that combines an MMS bookmark with a scale model. You will also find important URLs and QR codes for quick access to additional information about the mission. It makes the perfect visual aid when exploring giving talks about of the MMS mission while highlighting important connections to science, technology, engineering and mathematics.

MMS Bookmark Front Side
Front Side of Bookmark Acitivity:
The front side of the Bookmark Activity can be downloaded and displayed as is or cutout to make a 3D model of an MMS spacecraft.

Front Only | + Download | PDF | 505 KB
Front & Back | + Download | PDF | 730 KB
MMS Bookmark Backside
Back Side of Bookmark Acitivity:
The back side of the Bookmark Activity can be downloaded and displayed as is or cutout to make a 3D model of an MMS spacecraft.

Back Only | + Download | PDF | 166 KB
Front & Back | + Download | PDF | 730 KB
MMS Optional Bottom
Optional Bottom of Spacecraft:
Complete your model by downloading, cutting out and taping this ‘bottom section’ of the spacecraft to the ‘upper section’ of the spacecraft. Make sure that each of the numbered sides on the ‘bottom section’ match with the numbered panels found on the ‘upper section’.

Bottom Section Only | + Download | PDF | 139 KB

When printing the pdf, select a setting that will allow you to print pages 1 and 2 (front to back) on one piece of paper! When aligned properly, the entire activity can be cut out from one piece of paper (front to back).

The information on this page is identical to and in the same order as the information found on the printed MMS Bookmark/Activity. We've enhanced the content with additional information, definitions, images, links, videos and vodcasts.

From the Bookmark:

The MMS mission is composed of four identical instrumented spacecraft that will use the Earth's magnetic field as a laboratory in which to study a fundamental plasma process known as reconnection.

Earth and the magnetic reconnection

MMS will use a two-phase orbit strategy to explore two different regions where magnetic reconnection often occurs, one on the day side and the other on the night side of Earth. (Refer to the colored boxes in the image above.)


  1. Dayside Magnetopause: The location in space where Earth's magnetic field balances the pressure of the solar wind. It is located at the edge of the magnetosphere.
  2. Solar Wind: The plasma of charged particles coming out of the Sun in all directions at supersonic speeds.
  3. Plasmasheet: A sheet of plasma that extends down the magnetotail dividing the two lobes of the Earth's magnetic field.
  4. Magnetotail: The extreme extension of a magnetosphere, on the side of a planet opposite the Sun, caused by the solar wind.
  5. IMF: The interplanetary magnetic field (IMF) is the term for the solar magnetic field carried by the solar wind among the planets of the Solar System.


From the Paper Model Activity:

Each of the 8 panels found on the back of the Bookmark/Activity contain mission statistics, facts and/or ideas. We've enhanced that information with additional links, activities and resources.

Panel 1: Stats

MMS Spacecraft closeup
  • Width: 3.15 m
  • Height: 1.23 m
  • Weight: 1,250 kg
  • SDP-Wire Booms (x4): 60 m
  • ADP-Antenna Mast (x2): 14.75 m
  • Magnetometer Booms (x2): 5 m

See additional information about the MMS spacecraft dimensions and instrumentation

Image Key:

  1. SDP-Wire Booms
  2. ADP-Antenna Masts
  3. Magnetometer Booms

Panel 2: Fact

MMS Dayside Orbit Animation

“The four identically instrumented MMS spacecraft fly in an adjustable pyramid-like formation that enables them to observe the 3-D structure of magnetic reconnection.”

Watch Simulation:

View Additional Simulations and Videos:

View Vodcasts:

Panel 3: Activity

Optional Wire Boom Scale Activity

“Punch out this 1/31 scaled model of the MMS spacecraft. Fold down and tape the sides of each panel together. At this scale the wire booms would still be ~2 meters each!”

Optional (Wire Boom) Scale Activity:

  1. Cut 4 pieces of string at ~2 meters each.
  2. Locate the red dots on the image to the right. Identify and mark the same locations on your paper model. After constructing your model, tape one end of each string to one of the marks on your spacecraft. Stretch the other end of the string directly away from the center of the spacecraft.
  3. MMS Closeup of activity
  4. Your model should look similar to the image on the right.
  5. NOTE: Including the booms, each MMS spacecraft at this scale is over 4 meters wide!

Panel 4, 5 & 6: Scan

QR Codes make great enhancements to variety of educational objects and activities. Download and place these QR Codes on bulletin boards, notebooks, worksheets, scavenger hunts, etc.

QR Code for EPO Paper Model Page
This QR Code will take users directly to this Bookmark Activity on the MMS website:
MMS Home Page QR Code
This QR Code will take users directly to the home page of the MMS website:

Panel 7: Activity

Penny scale up closeA stack of 5 pennies represents a 1/164 scale model of an MMS spacecraft. At this scale the four MMS spacecraft orbiting in a pyramid-like formation would still be over 60 yards (or ~55 meters) apart! That's over half the length of a football field!

Scale model of MMS spacecraftStacking 5 U.S. Pennies together with tape created the base for this 1/164 scale model of the MMS spacecraft. Spaghetti strands (typically 26-cm in length) were used to simulate the 8 deployable booms.

Use the dimensions in the table below will help you create your own ‘US Penny Scale’ model of the MMS spacecraft.

Spacecraft Actual Scale ‘U.S. Penny’ Scale 1/164
Width 3.15 m 01.92 cm
Height 1.23 m 00.75 cm
SDP-Wire Booms (x4) 60 m 36.59 cm
ADP-Antenna Mast (x2) 14.75 m 08.99 cm
Magnetometer Booms (x2) 5 m 03.05 cm

Panel 8: Fact

MMS investigates how the sun's and Earth's magnetic fields connect and disconnect, explosively transferring energy from one to the other – a process that occurs throughout the universe, known as magnetic reconnection.

+ See the MMS Key Messages