Five CubeSats, small satellites which are, well, cubical in shape, were launched from the International Space Station last week.
The five devices each have different purposes and were put into orbit by a new robot arm, JAXA's Small Satellite Orbital Deployer, specifically designed for this purpose which was installed on the ISS last July.
CubeSats are very small, with a side of only 10 cm, 4 inches, and so are a lot less expensive than commercial or scientific satellites.
They're used for science experiments in particular, 75 have been put into orbit until these last five. The five small satellites are called Raiko, Niwaka (FITSAT-1), We Wish, TechEdSat, F-1.
NASA has published several photos shot aboard the ISS of the cubes departing the station. Astronaut Chris Hadfield called the sight surreal in a tweet. FITSAT-1, or Niwaka, is fitted with a number of LED lights and was used to broadcast a visible message in Morse code.