The paper presents the development of the power, propulsion, and thermal systems for a 3U CubeSat orbiting Earth at a radius of 600 km measuring the radiation imbalance using the RAVAN (Radiometer Assessment using Vertically Aligned NanoTubes) payload developed by NASA (National Aeronautics and Space Administration). The propulsion system was selected as a Mars-Space PPTCUP -Pulsed Plasma Thruster for CubeSat Propulsion, micro-pulsed plasma thruster with satisfactory capability to provide enough impulse to overcome the generated force due to drag to maintain an altitude of 600 km and bring the CubeSat down to a graveyard orbit of 513 km. Thermal analysis for hot case found that the integration of a black high-emissivity paint and MLI was required to prevent excessive heating within the structure. Furthermore, the power system analysis successfully defined electrical consumption scenarios for the CubeSat's 600 km orbit. The analysis concluded that a singular 7 W solar panel mounted on a sun-facing side of the CubeSat using a sun sensor could satisfactorily power the electrical system throughout the hot phase and charge the craft's battery enough to ensure constant electrical operation during the cold phase, even with the additional integration of an active thermal heater. However, when the inevitable end-of-life degradation of the solar cell was factored into the analysis, an approximate power deficit of 2 kJ was found. This was supplemented by additional solar cell integrated into the antenna housing face.Aerospace 2018, 5, 63 2 of 68 Tyvak, NanoRacks, Innovative Solutions In Space (ISIS) and CalPoly [2]. The nanosatellites are placed within an orbital deployer which safely releases the satellites into orbit after launch. The orbital deployer also helps to ensure the safety of the vehicle by encapsulating the satellites [3].As of 19 September 2016, a total of 479 CubeSats had been officially launched worldwide [2]. Of those launched, 210 are still operational and gathering data [2]. 70 nanosatellites were destroyed during launch [2]. A total of 40.8% of nanosatellites were launched by academic institutions, the highest of all categories [2]. This was followed by private companies in second with a total of 40.2% of all launches. Other major contributors included the military (5.3%) and space agencies (6.7%) [2]. The 3U CubeSat holds the market majority for chosen dimensions. 52.9% of all launched satellites conformed to these dimensions. The second most popular choice was the 1U configuration which had a 17.9% share of all launched types [4].Although the first CubeSat was launched in 1999 the number of launches has grown significantly in recent years. The first major advancement in launch numbers came in 2013. The launch number for this year was 87, a huge increase on the previous year's total of 25 [2]. This grew to around 150 per year in 2014/2015 and had peaked to 288 in 2016. There were 295 launches for 2017 [2] which highlights how rapidly this technology is advancing and the increasing rate at which it is be...