[hinkley]

I don't speak Japanese, but I can read "10cm" on the video overlay which seems to be about right.

10cm cube has a volume of 1 liter (10^3 ml). That's very wee.

[danpalmer]

That's the standard for a "cubesat". I believe the industry has standardised on 10cm^3 units for these satellites so that "ridesharing" or multi-party launches can work with less back and forth on systems integration between the satellite being launched and the launch vehicle.