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A CubeSat (''U-class spacecraft'') is a type of miniaturized satellite for space research made up of multiples of 10×10×11.35 cm cubic units, has a mass of no more than 1.33 kilograms per unit,〔 and often see the use of commercial off-the-shelf (COTS) components for its electronics and structure. CubeSats are most commonly put in orbit by deployers on the International Space Station, or launched as secondary payload Beginning in 1999, California Polytechnic State University (Cal Poly) and Stanford University developed the CubeSat specifications to promote and develop the skills necessary for the design, manufacturing, and testing of small satellites intended for low Earth orbit (LEO) that perform a number of scientific research functions and explore new space technologies. Academia accounted for the majority of CubeSat launches until 2013 when over half of launches were for non-academic purposes, and by 2014 most newly deployed CubeSats were for a commercial or amateur project.〔 CubeSats have been built by large and small companies alike, while other projects have been the subject of Kickstarter campaigns.〔http://singularityhub.com/2013/06/23/tiny-cubesat-satellites-spur-revolution-in-space/〕 Uses typically involve experiments which can be miniaturized or serve purposes such as Earth observation or amateur radio. Many CubeSats are used to demonstrate spacecraft technologies that are targeted for use in small satellites or that present questionable feasibility and are unlikely to justify the cost of a larger satellite. Scientific experiments with questionable underlying theory may also find themselves aboard CubeSats as their low cost could justify riskier experiments. Biological research payloads have been flown on several missions, with more planned. Several missions to the Moon and Mars are planning to use CubeSats. == History== The CubeSat reference design was proposed in 1999 by professors Jordi Puig-Suari of California Polytechnic State University and Bob Twiggs of Stanford University. The goal was to enable graduate students to be able to design, build, test and operate in space a spacecraft with capabilities similar to that of the first spacecraft, Sputnik. The CubeSat as initially proposed did not set out to become a standard; rather, it became a standard over time by a process of emergence. The first CubeSats were launched in June 2003 on a Russian Eurockot, and approximately 75 CubeSats had been placed into orbit by 2012. The need for such a small-factor satellite became apparent in 1998 as a result of work done at Stanford University's Space System Development Laboratory. At SSDL students had been working on the OPAL (Orbiting Picosatellite Automatic Launcher) microsatellite since 1995. OPAL's mission to deploy daughter-ship "picosatellites" had resulted in the development of a launcher system that was "hopelessly complicated" and could only be made to work "most of the time". With the project's delays mounting, Twiggs sought out DARPA funding that resulted in the redesign of the launching mechanism into a simple pusher plate concept with the satellites held in place by a spring-loaded door.〔 Desiring to shorten the development cycle experienced on OPAL and inspired by the picosatellites OPAL carried, Twiggs set out to find "how much could you reduce the size and still have a practical satellite". The picosatellites on OPAL were 10.1×7.6×2.5 cm, a size that was not conducive to covering all sides of the spacecraft with solar cells. Inspired by a 4-inch cubic plastic box used to display Beanie Babies in stores, Twiggs first settled on the larger 10-centimeter cube as a guideline for the new (yet-to-be-named) CubeSat concept. A model of a launcher was developed for the new satellite using the same pusher plate concept that had been used in the modified OPAL launcher. Twiggs presented the idea to Puig-Suari in the summer of 1999 and then at the Japan-U.S. Science, Technology, and Space Applications Program (JUSTSAP) conference in November 1999.〔 The term "CubeSat" was coined to denote nanosatellites that adhere to the standards described in the CubeSat design specification. Cal Poly published the standard in an effort led by aerospace engineering professor Jordi Puig-Suari. Bob Twiggs, of the Department of Aeronautics & Astronautics at Stanford University, and currently a member of the space science faculty at Morehead State University in Kentucky, has contributed to the CubeSat community. His efforts have focused on CubeSats from educational institutions. The specification does not apply to other cube-like nanosatellites such as the NASA "MEPSI" nanosatellite, which is slightly larger than a CubeSat. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「cubesat」の詳細全文を読む スポンサード リンク
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