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Japanese Rocket Technology Advances
Space Exploration

Part 1

Japanese Rockets at the Forefront of the Aerospace Industry

On December 2011, the 53-meter high H-IIA rocket No. 20 took off from the Tanegashima Space Center and launched its satellite payload into Earth orbit. Developed in Japan, the rocket's reliability is notable: 95% of H-IIA rockets have launched successfully since the vehicle's maiden flight ten years ago. Japan's H-IIA rocket is in fact one of the most dependable in the world.

H-IIB rocket

H-IIB rocket launching the HTV Kounotori ©JAXA

Japan's aerospace success is not limited to the H-IIA rocket. Launched in 2003, the space probe Hayabusa returned to Earth in 2010 carrying the first samples to be taken from an asteroid farther away than the moon. The science satellite Hinode was launched in 2005 to study the sun. The M-V rocket, propelled by solid fuel, was used for the launch of both spacecrafts. In January 2011, the H-IIB rocket—an upgraded version of the H-IIA—launched the HTV Kounotori, a supply vehicle for the International Space Station (ISS). With this record, Japan is currently one of the world leaders in both space exploration and rocket development.

Japanese Rocket Development Began with "the Pencil"!

Dr. Itokawa

Dr. Itokawa, with a Pencil rocket in his hand ©JAXA

At a height of 56.6 meters, the H-IIB is the result of many years of research and development. Japanese rocket development commenced in 1954, not many years after the end of World War II. It was led by Professor Itokawa Hideo of the Institute of Industrial Science at the University of Tokyo. Initial steps involved experiments on the horizontal launch of rockets propelled by solid fuel. The solid-fuel rockets were 23 centimeters high and weighed 250 grams; they were so small that they were called "Pencil rockets." The next rocket developed in the Japanese space program was the 120-centimeter-high Baby rocket. It was subsequently improved to become the K (Kappa)-1 rocket, which reached an altitude of 10 kilometers.

The M-V rocket

The M-V rocket, propelled by solid fuel ©JAXA

The next phase in the program aimed to launch a manmade satellite into Earth orbit. It was achieved in 1970 with the L (Lambda)-4S5 rocket, which successfully launched the Ohsumi. Japan was only the fourth country in the world to do so, following satellite launches by the Soviet Union, the U.S., and France. After the Ohsumi, Japanese solid-fuel rockets launched a number of spacecrafts, the most recent being the Hayabusa, launched by the M-V5 rocket. The asteroid on which the Hayabusa landed was named Itokawa after the scientist who pioneered the Japanese space program. The landing signified that Japanese rocket scientists, whose work in space exploration had begun with the simple Pencil rocket, had finally reached the world's foremost level in space technology.

Hayabusa, A particle taken from the asteroid Itokawa

Left: Launched with the M-V5, the space probe Hayabusa headed for the asteroid Itokawa (artist's rendering) ©Akihiro Ikeshita
Right: A particle taken from the asteroid Itokawa back to earth by the Hayabusa ©JAXA