If you closely follow space exploration, or read Solution Analyst Melissa Winter’s recent blog post found here, you’ve heard of CubeSats. For readers who haven’t, they are tiny satellites that are becoming more popular every year. Stanford University’s Space Systems Development Laboratory (SSDL) developed a set of specifications required to label a satellite a CubeSat. The scientists at SSDL set the standard size as a cube with side length of 10 cm (labelled as a size of “1U”), but these satellites can also be the same size as multiple 1U cubes stacked on top of one another. One of SSDL’s goals was to make university created space projects more affordable, and therefore more plausible.
In her blog, one of Melissa’s main points was that there is a lack of data to predict the costs of CubeSats. This is mostly because the technology and commercialization of these satellites is still in its infancy stages. This blog is intended to discuss some main cost drivers in estimating costs for CubeSats. My research has shown that several factors affect program cost: weight, launch costs, the use of Commercial Off The Shelf (COTS) parts, reuse of past designs, and student participation.
CubeSats are hundreds of times smaller than their traditional counterparts. Their mass usually ranges from about 1 kg to 18 kg, whereas the Wideband Global Satcom-8 mentioned previously has a mass of 3,400 kg. Due to their size, CubeSats can be a part of launch vehicle’s secondary payload with many other satellites. Thus, a company like SpaceX that charges $62 million for 5,500 kg worth of payload can charge around $350k to send a CubeSat to space. Though greatly reduced, launch costs are still a significant portion of a CubeSat mission that typically costs a couple million dollars.
In addition, many of these satellites are made up of COTS, which are pre-made parts. Buying commercial components can be cheaper than the alternative of building ones in-house. Similarly, recent projects may reuse designs or parts from previous missions. For example, O/OREOS, another NASA creation, reuses subsystems from previous CubeSats made by that organization. Both practices can reduce labor and design costs for that part, even if it needs to be modified.
Student involvement in the project also impacts cost. CubeSat projects carried out by universities have students doing much of the work. These students may work for college credits which is, of course, at no cost to the project. Even if the students on the project are being paid, it will be at a lower rate than a professional worker. This will cause these projects to have a much lower price tag. On a side note, it has been proposed to consider a separate cost model to approximate the cost of academic CubeSat projects. After attempting to estimate these projects, I would have to agree.
CubeSats are typically Earth orbiting satellites only. In May of this year that changed when NASA launched an interplanetary mission, MarCO. Based on previous research done at PRICE, planetary missions tend to cost more than similar ones that stay near the Earth. NASA’s attempt at a planetary CubeSat demonstrates that these unique satellites are becoming a permanent part of space exploration. I’m looking forward to doing more research on this as more information becomes available.