One of the most important aims of life science experiments in space is to study the effects of gravity on life, which is always subject to the earth's gravity. Such experiments have been carried out in orbiting artificial satellites and space shuttles. To identify the effects of gravity itself on orbit, it is important to create stable control experiment environments where other parameters, such as cosmic rays and electromagnetic waves are as identical as possible, and to specify the effect only of gravity. Creating on-orbit experiment conditions is difficult in ground-based experiments, but creating gravity in orbiting laboratories is easier, ensuring better contrast experiments. In order to create a gravitational environment in orbiting laboratories, gravity can be created by rotation part to generate centrifugal force on it. Larger rotation diameters are better to reduce the effects of Coriolis force and gravity gradients, but there is space limitation to the space available for spacecraft. In Kibo, the Japanese experiment module in the International Space Station (ISS), there is an orbiting experiment facility for centrifugal life science experiments. The facility has one of the largest rotation diameters in ISS by optimizing the available laboratory space. This facility can create gravity less than 1G by centrifugal force, which is difficult to create in ground-based facilities and keep it stable for a long time. The facility also can simulate gravity equivalent to such as Luna surface and Mars. Mitsubishi Heavy Industries, Ltd. (MHI) developed the experiment facility with a large centrifuge (rotation radius: 38 cm), which has operated since 2020. This report outlines the development and the first mission of the facility.
