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The inflatable antenna for CubeSat is a 1 meter antenna reflector designed with one side reflective Mylar, another side clear Mylar with a patch antenna at the focus. The development of this technology responds to the increasing need for more capable communication systems to allow CubeSats to operate autonomously in interplanetary missions. An initial version of the antenna for the S-Band was developed and tested in both anechoic chamber and vacuum chamber. Recent developments in transceivers and amplifiers for CubeSat at X-band motivated the extension from the S-Band to the X-Band. This paper describes the process of extending the design of the antenna to the X-Band focusing on patch antenna redesign, new manufacturing challenges and initial results of experimental tests. I. Introduction UBESATS 7 are now providing innovative means to explore space. They are made mostly of COTS products, they are designed and prototyped very quickly and they allow a fast turnaround from proposal to launch and operation. As a result, there is an increasing interest in the aerospace community (academia, industries and space agencies) in using CubeSat for deep space/ interplanetary missions. However, CubeSats were originally conceived mainly with the goal of operating in Low Earth Orbit (LEO) and technological advancements are required to move Cubesats from LEO to deep space. Specifically, one of the areas of research in the field of interplanetary CubeSats is communication: as Cubesats move farther in the solar system new solutions need to be developed to allow the small satellites to close the link. Current work in this area includes developments in antenna design (deployable as in Ref. 1, reflectarray as in Ref. 2 and 3, inflatables as in Ref. 4), amplifiers and transceiver designs (Ref. 5, 6, and 7), coding (Ref. 8), CDMA (Ref. 9 and 10), multiple spacecraft per antenna (Ref. 11), optical communication (Ref. 12), and collaborative communication (Ref. 13). This paper focuses on the inflatable antenna technology. The antenna is an inflatable parabolic reflector made of one side reflective Mylar, another side clear Mylar with a patch antenna at the focus. An initial version of the antenna for the S-Band was developed and tested in both anechoic chamber and vacuum chamber in Ref. 14. The simulated and experimental results in Ref. 15 showed that the antenna can achieve a considerable gain (16-20 dB) for a CubeSat and it can be packaged in less than 0.5 U. In addition, the inflation mechanism is performed using sublimating powder (benzoic acid) which eliminates any need for carrying pressure vessels on board. This lightweight, efficiently packaged high gain antenna can be very promising for future interplanetary CubeSat communication, especially for its unique stowing efficiency (20:1), which differentiate the antenna from deployables and reflectarrays antennas currently in development in Ref. 1 and 2.

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We advocate a low-cost strategy for long-duration research into the ‘milligravity’ environment of asteroids, comets and small moons, where surface gravity is a vector field typically less than 1/1000 the gravity of Earth. Unlike the microgravity environment of space, there is a directionality that gives rise, over time, to strangely familiar geologic textures and landforms. In addition to advancing planetary science, and furthering technologies for hazardous asteroid mitigation and in situ resource utilization, simplified access to long-duration milligravity offers significant potential for advancing human spaceflight, biomedicine and manufacturing. We show that a commodity 3U (10 × 10 × 34 cm3) cubesat containing a laboratory of loose materials can be spun to 1 r.p.m. = 2π/60 s−1 on its long axis, creating a centrifugal force equivalent to the surface gravity of a kilometer-sized asteroid. We describe the first flight demonstration, where small meteorite fragments will pile up to create a patch of real regolith under realistic asteroid conditions, paving the way for subsequent missions where landing and mobility technology can be flight-proven in the operational environment, in low-Earth orbit. The 3U design can be adapted for use onboard the International Space Station to allow for variable gravity experiments under ambient temperature and pressure for a broader range of experiments.