As traditional satellites successfully utilize extensible structures such as long magnetic booms or large antennae, the variety of space missions to be realized by nano-scale satellites would be greatly expanded if they employed such structures. Specifically for remote sensing applications, extensible structures are convenient for achieving long focal lengths required by the optics system. In our laboratory, a nano-scale remote sensing satellite “PRISM” has been developed with an expected launch date in the 2008 fiscal year. PRISM has an extensible boom with a telephoto lens at its tip, creating a refractive telescope, which on the orbit can acquire earth images with a resolution better than 30m. In this paper, we describe the design of the boom and present results from a micro-gravity experiment where the operation and system identification tests were performed.