Japan was the 4th country to launch a satellite into orbit using their own launch vehicle and they managed to do this despite not being able to use any guidance systems on their early rockets because of legal prohibitions on weapons development which included long range rockets. This meant using a clever launch system that placed the rocket at the correct angle to begin a gravity turn to take them to space.

JAXA's story on the Pencil rocket development
https://global.jaxa.jp/article/interv...

Jonathan McDowell's paper on the Kappa and Lambda sounding rockets.
https://www.planet4589.org/space/pape...

JAXA's own site on these launch vehicles.
https://www.isas.jaxa.jp/en/missions/...

Open Aerospace details about Lambda 4s
https://open-aerospace.github.io/Lamb...

Norbert Brugge's Spacerockets site on Japan's launch vehicles.
http://www.b14643.de/Spacerockets_1/J...

My own video on the SS-520 from a few years ago
   • The Smallest Rocket - The SS-520-5  

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