Students in North Carolina Tackle Light Pollution with Cube Satellites

How six students from UNC Asheville are creating a tool to help support Lights Out initiatives in North Carolina and beyond.

One of the biggest challenges to getting Lights Out programs adopted into official city ordinances is a lack of data on light pollution and its effects. For a group of students at University of North Carolina (UNC) Asheville, that challenge was an opportunity.聽

The tale聽starts with , a senior at UNC Asheville, member of Blue Ridge 爆料公社, and the vice president and treasurer of . One day, Jones gave a presentation about Lights Out to her聽ethics class.聽She specifically focused on Blue Ridge 爆料公社's work on the initiative, and the collaboration between Blue Ridge 爆料公社 and the UNC Asheville campus chapter to create the Bird-Safe Asheville Coalition, which .聽That presentation sparked an idea in the mind of a fellow student, Katrina Schubert: create a low-cost tool to accurately measure light pollution. That way, Bird-Safe Asheville could get the data it needs to help turn that proclamation into an enforceable city ordinance.

鈥淲e spent our first month of academic work here going through a number of ideas, none of which resonated,鈥 says Katrina Schubert, original project lead and mechatronics engineering student at UNC Asheville. 鈥淧aulina talked to our class about these Lights Out ordinances and I thought 鈥榶ou know what would be useful, a tool that could help measure light pollution on a local scale.鈥 And our team thought it was a workable idea.鈥

Their team is made up of six mechatronic engineering students that assembled聽in August 2021 for their senior design project. The project was to create a CubeSat, a miniature cube satellite, to take pictures measuring light pollution. Their design included a gimbal that rotates聽along three聽axes, a camera with adjustable聽shutter speed, weather sensors, Raspberry Pi chipsets, insulation against inclement weather, and a parachute. All of this had to be precisely stabilized because it would be tethered on to a helium balloon. And it had to be simple enough to be聽accessible for anyone to use.

鈥淐reating this tool that captures much more localized data is what we're shooting for and one that is low cost,鈥 says Schubert. 鈥淲hen you're looking at light pollution data that is available, most of it is taken from space, and so you have a high-level view of what's going on. The goal here was to bring that high or macro level view down to the micro view and be able to target certain regions to get that data to the people that need it to create legislation. Which is to help handle some of the problems that are currently going on.鈥

What on the surface level was supposed to be an 鈥榚asy straightforward project鈥 soon became a challenge as they needed to fit all their technological innovation聽into a tiny package聽and be financially and technologically accessible. Some of those challenges included designing the gimbal and testing the response time of the stabilization motors. Even聽finding the right ISO speed for their camera proved to be fraught. And, as with everything else in 2022, supply chain issues created their聽own headaches.聽For the gimbal, the students needed a control board that was not too expensive, but of course it was backordered. Even the weather refused to cooperate and the team had to scrub some test launches for safety reasons.聽聽

鈥淚t would be much less challenging if we were trying to just take normal photographs,聽but since we're trying to take night shots,聽you have to stabilize a camera for a longer period,鈥 says the team鈥檚 new lead, Samuel Julian. 鈥淲hen you talk about something floating in the air, bobbing back and forth, and you're still trying to take a very still image, it becomes an advanced engineer problem.鈥

One thing that was not a huge problem were聽their finances. Their total budget was $5,000, and by their midterm presentation, the team had $2,450 left over that they could use for 鈥榰nexpected purchases.鈥 To keep prices down, the students聽use tools that can be printed from 3D printers and boards that can be easily purchased. Outside groups are聽interested in the design and want to expand this project to be used on a larger (more expensive) scale to be launched into space. But, according to聽Schubert, that is not what the UNC Asheville team聽is focused on.

At press time, the team had worked out most of their technical issues and are聽planning to conduct聽test launches in clearer skies. They have received their 3-axis controller and have it moving and functioning, but will continue to work on the cube sat platform through the rest of the semester聽and calibrate it before their next launch.聽

鈥淲e need to get the physical thing moving and working. The majority of the work we鈥檝e done is getting this thing in the air and taking the readings,鈥 says Schubert. 鈥淎ll in all, we just wanted to create a tool that would be useful for organizations like the 爆料公社 Society to present [light pollution] data to lawmakers to create change.鈥