Bread Loaf-Sized CubeSat Demonstrates Method for Reducing Space Junk

Every year over one hundred CubeSats are launched into space. The small satellites serve a variety of purposes but are mainly used to study science, exploration, technology, and serve educational purposes. In fact, about two-thirds of all CubeSats launched were for civil purposes with twenty five percent being from academic organizations. Recently, a team of students from Brown University launched their own CubeSat on a budget of about $10,000.

The project originated out of a class at Brown University called “Design of Space Systems” taught by professor Rick Fleeter. The idea began when Fleeter was approached by D-Orbit, an Italian aerospace company, about an opening for a satellite on a future SpaceX Falcon 9 rocket launch. The students then quickly began brainstorming and designing the satellite to fit in a 3U CubeSat chassis. CubeSats are generally built into standard sizes such as 1U, 2U, 3U or 6U. A 1U size is 10 cm x 10 cm x 10 cm, where as a 3U size is 10 cm x 10 cm x 34 cm. Furthermore, they are also generally designed to weigh less than 3lbs, or 1.33kg.

The CubeSat was named SBUDNIC, a play on the name of the first satellite to orbit Earth, Sputnik, as well as an acronym for the participating parties. It was built using off the shelf supplies such as an Arduino for onboard data handling, a commercially available high strength aluminum alloy 3U frame, and a Hamshield Mini for tracking, telemetry, and control. It is also believed to be one of the first CubeSats launched into space made almost completely out of materials not designed to be launched into space. “The large complex space missions we hear about in the news are amazing and inspiring, but they also send a message that space is only for those types of specialized incentives,” mentioned Fleeter. “here, we’re opening up that possibility to more people… We’re not breaking down all barriers, but you have to start somewhere.”

Analysis of recent data from the CubeSat shows the launch and operation has been a success. Moreover, it has also shown a novel technique included in the satellite build can be used in the future to help reduce space junk. Space junk is classified as debris in orbit such as non-functioning satellites, abandoned pieces from rockets, and fragmentation debris. NASA has stated that over 27,000 pieces of space junk are being tracked by the Department of Defense in orbit around the Earth.

The technique the students included as a potential solution was implemented as a 3D-printed drag sail. The drag sail was made from Kapton polymide and was opened upon deployment at 520km. It works by helping to bring the CubeSat down to Earth sooner than a device without a drag sail. Not only does the data show it will re-enter Earth’s atmosphere sooner than other devices launched at a similar time, but it will be out of orbit 5 times sooner. That is a difference of 25 years to 5 years. “The theory and physics of how this works has been pretty well accepted,” stated Fleeter. “What this mission showed was more about how you realize it – how you build a mechanism that does that, and how you do it so it’s lightweight, small, and affordable.”