Small Carry-on Impactor (SCI) is a deployable instrument for creating artificial crater on asteroid by impacting a liner. The liner is 2 kg copper lump, because copper can be easily separated from the asteroid's sample. By ignition of an explosive, liner will be ejected at a high speed, about 2 km/s, and while chaging its shape. This experiment will enable us to access subsurface materials which will not be affected by space weathering.