In 2020, Aurorasaurus partnered with NASA’s STEAM Innovation Lab and NASA’s Magnetosphere Multiscale Mission (MMS) to design and create the world’s first 3D printed magnetosphere model. We have just released the beta version (1.0) and are excited for educators, Makers, Subject Matter Experts (SMEs), and the general public to beta test it on printers and with audiences—and to add their own innovations.
A New Model
Despite the idiom “empty space,” outer space is not empty. The Earth is surrounded by a vast, invisible magnetic force field that protects our planet from the solar wind: torrents of particles and magnetic ﬁelds streaming from the Sun. The interaction between these particles and the magnetic field, or magnetosphere, is fundamental to how auroras are made.
The magnetosphere around Earth is made up of a soup of charged particles called plasma. The plasma separates electrically and magnetically, with plasma populations differing in energy, density, and motion. While there are many regions, the 3D Printed Magnetosphere Model simplifies to the following: Magnetopause, Plasma Sheet, Outer Radiation Belt, Ring Current, Auroras, and Earth (including Inner Core, Outer Core, Mantle, and Crust). Users can move, rotate, and disassemble parts of the model so that each piece can be examined by itself or as part of a system.
In this post, we walk you through one of the science stories that this model illustrates, while giving you a behind-the-scenes look at the way the model was developed.
A Sun-Earth Story
On approaching Earth, the solar wind first encounters the planet’s magnetopause, the boundary of the magnetosphere formed by the interaction of the solar wind with Earth’s magnetic field. On our 3D print of the model, this is represented by a dark blue shell that acts as a case, opening along the x axis.
The sunward side of the magnetopause is compressed by the solar wind, while the side away from the Sun is stretched into an extremely long, comet-like “magnetotail.” The magnetopause can also change size and shape depending on the strength of the solar wind. In order to fit on 3D printers, the magnetotail of the 3D Printed Magnetosphere Model is truncated—but the full length could be illustrated with an add-on, like a piece of fabric sewn like a windsock. Particles from the solar wind enter the noon-aligned “nose” of the magnetosphere, then move via convection to the magnetotail.
The magnetosphere also has two funnel-like “cusps” over its poles: direct entry points for the solar wind into Earth’s atmosphere. These help cause the rarely-seen, daytime “cusp aurora“.
Note: While the blue shell technically represents the magnetopause, we named the corresponding files “magnetosphere” because they encase all of the structures in the 3D Printed Magnetosphere Model. The scientific term “magnetosphere” includes all of the structures.
The Plasma Sheet
Plasma that entered the magnetosphere from the dayside is moved to the nightside via convection and stored in the stretching magnetotail. The plasma sheet is a flattish equatorial plane of denser plasma and a weaker magnetic field. On the model, a white shelf representing the plasma sheet equatorial plane is labeled with important structures and concepts, including the flow of plasma and directions relative to the Sun. We have had suggestions that there could be several alternate versions that users could swap out to illustrate changing conditions, as well as other features like plasma waves. Another idea was to cover one side with a dry-erase decal and have students label different aspects. What would you add?
The plasma sheet surrounds and connects with the ring current (pictured in grey), an electrical current carried by energetic particles that encircles our planet at a distance of approximately 6,200 to 37,000 miles (10,000 to 60,000 km). The ring current drives a global system of electrical currents both in space and on Earth’s surface, which during intense geomagnetic storms can severely damage technological systems. In the ring current, ions move clockwise and electrons move counterclockwise. As the Earth rotates underneath the oval-shaped area where the aurora is most active, the different particle directions relate to different kinds of auroras on the side of the earth closest to dawn and the side closest to dusk.
The Radiation Belts
Moving toward the Earth, plasma is energized to form the Van Allen Radiation Belts: dynamic areas of high-energy charged particles that surround the Earth. The Outer Radiation Belt is represented in the 3D Printed Magnetosphere Model by a light blue torus, or “doughnut”. The Inner Radiation Belt is not represented on this version of the model; there wasn’t room. The Radiation Belts can damage satellites in geosynchronous orbit (marked GEO on the model) and present radiation hazards to astronauts. Their intensities are affected by solar geomagnetic storms. In order to learn more about them, the NASA Van Allen Probes Mission studied these regions from 2012-2019, using satellites. Designer Patrick Haas created two alternate support systems for suspending these features inside the model, both of which are provided.
Finally, the plasma reaches the Earth. Energized by the journey through the magnetosphere, particles sleet into the upper atmosphere, energizing atoms and molecules at altitudes between 100 to more than 500 kilometers (60 miles to more than 300 miles). These atoms and molecules in turn give off auroral light. Representations of the auroral ovals fit around the northern and southern magnetic poles at the cusp insertion points. Since the Earth rotates underneath the auroral oval, the aurora pieces are able to rotate separately.
How did the magnetosphere come to be? The Earth itself is represented by two hemispheres held together by magnets. They are intended to come apart and reveal the planet’s crust, outer mantle, inner mantle, and core. Convection in the mantle layers generates the Earth’s magnetic field by an internal dynamo and it extends out into space.
How do you think your learners would respond to each of these pieces?
Technical Specs and Considerations
Dimensions with all pieces assembled are 231mm long x 155mm wide x 152mm high. While it’s pretty close, the 3D Printed Magnetosphere Model isn’t quite to scale. We made it a priority for this model to be accessible to a range of printers, so we had to make some compromises. The maximum size is limited by the size of 3D printer beds, while the minimum size is limited by printability. The largest pieces of the model require a printer that has a print volume of 240mm x 200mm and at least 80mm high, with 0.2mm layer (z resolution) minimum. This project requires a large number of parts that must fit into one another with fairly tight tolerances. Lead Designer Patrick Haas created novel, printable interfaces and geometries, and thoroughly test-printed each to ensure that other makers will be able to print successfully.
Version 1.0 beta testing is only the start for the 3D Printed Magnetosphere Model! We invite Makers, SMEs, and educators to hack and refine the files, or to collaborate with us! We are interested in making the shapes more closely represent snapshots of magnetospheric structures, and including more tactile accessibility features. Another idea is a printable hinge mechanism that joins the two halves of the Magnetosphere and is sturdy enough for classroom use. Stay tuned to Aurorasaurus and NASA’s STEAM Innovation Lab for future updates!
We hope that the 3D Printed Magnetosphere Model helps you share the science and wonder of our planet, and welcome feedback! How are you using your model? If you have any ideas that we could implement in future versions, please let us know by filling out this survey. If you have created an alternate or refined version, please post your make and tag us on Twitter @TweetAurora and @NASAHEAT, with the hashtag #3DMagnetosphere!