Monitor of All-sky X-ray Image (MAXI) Masaru Matsuoka (Leader), Shigenori Komatsu, Kenichi Torii, Mutsumi Sugizaki, Hiroshi Tomida, Shiro Ueno, Yuji Shirasaki, Masaaki Sakano, Weimin Yuan (NASDA), Nobuyuki Kawai, Atsumasa Yoshida, Tatehiro Mihara, Hitoshi Negoro (RIKEN), Hiroshi Tsunemi, Emi Miyata (Osaka University) MAXI achieves unprecedented sensitivity MAXI has been selected as one of the first payloads to be attached to Japan Experiment Module (JEM-Kibo) of the International Space Station (ISS). MAXI will scan the whole sky once every orbit, 24 hours a day, and will determine the position, the brightness, and the color of every X-ray object brighter than 1 mCrab (a conventional flux unit in X-ray astronomy). Targets of MAXI MAXI will be the first all-sky X-ray monitor to expand our scope to extra- galactic objects. The X-ray time- variability of about 1000 astronomical objects will be monitored on the time scales ranging from a day to months during the MAXI operation, two years at least. The international astronomical community will be swiftly informed of significant flux changes detected with MAXI through the Internet, so that they can make follow-up observations. MAXI Radiator for X-ray CCDs Grapple Fixture for a robot arm Electronics Optical Star Sensor 77cm 80cm Solid-state Slit Cameras (SSC) = X-ray CCD cameras 185cm Gas Slit Cameras (GSC) = X-ray gas counter cameras Total weight: 500 kg