Lesson Plans

Every engineering project starts with an idea, a quest to design and build something new.

• Artist Trevor Paglen had been imagining a "nonfunctional" satellite for years, but had not found the right partner or moment in his practice to bring this vision to life
• In 2015, Paglen approached the Nevada Museum of Art to imagine the unimaginable: Create a satellite to exist purely as an artistic gesture
• Serving no commercial, scientific, or military purpose, Orbital Reflector was conceived of as a large reflective balloon that would orbit the planet
• The challenge would require a collaboration between the artist, the Museum, scientists, and engineers

All engineering designs must meet the specific requirements of the project. Orbital Reflector had to be designed to meet the following factors:

• Must reflect sunlight from space onto the earth below
• Must be visible from the surface of the earth with the naked eye
• Entire assembly must fit within the volume of the CubeSat (10 cm x 10 cm X 30 cm)
• Entire assembly must weigh fewer than five kilograms
• Requires one-way radio communication or the ability to receive a transmitted signal from Earth
• CubeSat must facilitate balloon inflation
• Inflated balloon must be able to withstand extreme temperature fluctuations and solar winds
• Must stay in low Earth orbit for a minimum of 60 days
• Entire assembly must burn-up upon reentry through the atmosphere

An early prototype of Orbital Reflector was built, today this prototype hangs in the atrium of the Nevada Museum of Art. The prototype was built to the following specifications:

• Inflatable silver Mylar sphere, 14 feet in diameter
• Visibility (albedo) measurement of 0.89.
• The balloon structure could be easily packed and folded inside of a small brick-shaped CubeSat
• The CubeSat was engineered with a hinged door, to release the balloon
• The CubeSat contained CO2 cartridges, to inflate the balloon once in orbit
  The CubeSat contained a software system capable of triggering in-flight procedure
• Solar panels affixed to the CubeSat, serve as a back-up power system for the internal battery pack
• A small radio antenna (utilizing HAM radio frequency) was affixed to the CubeSat. The signal transmits to a ground station, creating a "call and response" method for in-flight evaluation

Working with a team of aerospace engineers, the Orbital Reflector team evaluated the prototype of the satellite. During the Preliminary Design Review, we discussed the following concerns:

• The spherical shape and Mylar material were not reflective enough and could not achieve the recommended albedo
• The spherical shape was also a concern for the life of the mission, the balloon might be too fragile in extreme solar winds
• Assembling a spherical balloon from sheets of Mylar would require multiple seams, creating multiple points for potential failure
• If the software-system that triggers the door hinge and balloon inflation failed, there was no back-up. It was determined that building two independent systems would help mitigate against any software failure

After the Preliminary Design Review, the artist needed to conceive of a new shape for the satellite that would be more visible, more stable in orbit, and with less seams. These were the solutions:

• Create a longer, flatter shape, with a larger reflective surface to increase visibility
• Considering a new shape and the aesthetics of the balloon, the artist conceived of a form geometrically similar to a triangle: a diamond
• The new diamond-shaped balloon would be 100 feet long by five feet wide
• The balloon would be made of polyethylene, a thin plastic material, coated in titanium dioxide powder to increase reflectivity

A team of engineers from the aerospace firm Global Western worked with Trevor Paglen and the Nevada Museum of Art to design, build and test the new prototype of Orbital Reflector. These are the results of our Critical Design Review:

• Orbital analyses models revealed that diamond shape balloon would achieve, and likely surpass, the desired 60-day minimum mission life
• The diamond shape assembly required fewer seams, making for a more solid construction
• Further evaluation illustrated that the flatter shape would help to mitigate against potential debris encounters: should the balloon be pierced in-flight, the large, flat surface would still fly, and still be visible from Earth with the naked eye
• The polyethylene material proved more pliable, and better suited to space conditions than Mylar
• The titanium dioxide coating proved to be xxx times brighter than Mylar
• Modeling revealed that two small CO2 cartridges would supply the necessary amount of gas to inflate the balloon in a space environment. Given that there is no atmosphere, only a small amount of pressure was needed inside the balloon for successful inflation
• The balloon assembly team constructed six balloons in total, three of the flight-preferred length, and three of various shorter lengths for testing and prototyping.
• During prototype construction, two different door designs were built and evaluated: a single-hinged door and a double hinged door. Testing revealed that a single-hinge door system was preferred

The flight unit consists of all the various parts included in the final design. In addition to the balloon, this includes the housing, the hardware, and the CubeSat construction. After the Critical Design Review of the balloon, the overall flight unit had to be specified, assembled and tested. These are the results of the design review and testing of the flight unit:

• The CubeSat units were constructed using a combination of standard parts like radio controllers, antennae, fasteners, as well as specially-designed components fabricated with a CNC cutting machine
• In one test, the balloon was punctured by the fasteners that attached the balloon to the base plate. The internal fasteners were redesigned to adjust these protrusions, mitigating the likelihood of puncturing
• Once the flight unit was fully assembled, it underwent significant flight-ready testing:
  • Dynamics, otherwise known as "shake and vibe" testing, prove that the unit can withstand the rocket launch
  • Thermal vacuum testing proves that the satellite can perform in extreme temperature environments
• Two independent flight units were fully assembled to mitigate risk, one flight unit served as a back-up     

Once the final design had been successfully tested, these plans had to be shared with our launch provider, SpaceX. Orbital Reflector would be one of many secondary payloads carried into orbit by the Falcon 9 Rocket and Space X is responsible for coordinating how all the various payloads will eject. These are the results of our launch integration:

• The overall mass and volume of the flight unit design was shared with the launch provider, so that an independent analysis of satellite deployment can be performed, deciding what order the payloads would be deployed into orbit
• The launch provider reported that our balloon would wait a minimum of 10 hours from rocket ejection until we could deploy from the CubeSat
• Software engineering adjustments had to be made to the flight unit in order to account for the wait time
• Re-testing occurred with these new software and deployment adjustments
• The final design is submitted and approved for launch

Communicating the results of the Engineering Design Process is an important final step in any undertaking. During this final phase, we are reminded of what makes Orbital Reflector a real-world example of STEAM practice, uniquely poised to bring art and design-based thinking to the forefront of STEAM Education.

In communicating the results of a successful design process, we can now begin to consider the implications of the artwork in orbit.

View in orbit, Impact etc.