The Complete Book of Spaceflight: From Apollo 1 to Zero Gravity

J-1 (Japanese launch vehicle)
A Japanese three-stage solid fuel rocket able to place payloads
of about 1,000 kg into low Earth orbit. The J-1 was
the first launch vehicle in Japan to be made from a combination
of existing indigenous rockets—the solid rocket
booster of the H-2 (see H series) and the upper stage of
the M-3S II (see M series). The Japanese space agency
NASDA had hoped that using existing systems would
keep cost and development time down. However, when a
report showed that the J-1 program cost more than similar
projects in other countries, NASDA switched to
developing a more capable rocket, the J-2, using less
expensive parts imported from overseas. The J-2 will
employ a single Russian NK-33 first-stage engine and fuel
tanks derived from the Atlas; it will be able to place
approximately 3,500 kg into a 160-km-high orbit and
1,000 kg into a sun-synchronous orbit. The first test flight
is planned for 2006.
J-2 (American rocket engine)
An American liquid-propellant rocket engine, manufactured
by Rocketdyne, that ranks among the most important
in the history of manned spaceflight propulsion. The
J-2 was the first manned booster engine that used liquid
hydrogen as a fuel and the first large booster engine
designed to be restarted multiple times during a mission.
It was so versatile that it was used for both the second
and third stages of the Saturn V and, in modified form,
was also used to demonstrate principles that led to the
development of the Space Shuttle Main Engine. Capable
of providing about one million N of thrust, the J-2 featured
independently driven pumps for liquid oxygen and
liquid hydrogen, a gas generator to supply hot gas to two
turbines running in series, and pneumatic and electrical
control interlocks.
Japan in space
See Japanese launch vehicles, Japanese satellite names,
Tokohiro Akiyama, HOPE, ISAS, ISAS missions,
Kagoshima Space Center, NASDA, and Tanegashima
Space Center.
Japanese launch vehicles
The postwar story of Japanese rocketry began in 1955
with small solid-propellant rockets at the Institute of
Industrial Science, Tokyo University, and led to a series
J
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of sounding rockets known as Kappa. Following this
came the larger-scale Lambda, or L series, which
launched Japan’s first artificial satellite in 1970. More
recent developments have included the M series, used
by ISAS (Institute for Science and Astronautical Science),
and the N series, H series, and J-1, used by
NASDA (National Space Development Agency).
Japanese satellite names
Both of Japan’s space agencies, ISAS (Institute of Space
and Astronautical Science) and NASDA (National Space
Development Agency), tend to give two names to their
satellites, one English and one Japanese. However, these
two names are completely unrelated, which can be confusing.
For example, NASDA’s ETS (Engineering Test
Satellite) series is also referred to by the Japanese name
Kiku, which means “chrysanthemum.” Many of NASDA’s
satellites are similarly named after flowers—Momo (“peach
blossom”) for MOS (Marine Observation Satellite), Sakura
(“cherry blossom”) for the CS series of communications
satellites, and Ajisai (“hydrangea”) for EGS (Experimental
Geodetic Satellite). ISAS, on the other hand, uses
national names that are more diverse and sometimes
loosely linked to the spacecraft’s mission, such as Haruka
(“far away”), Tenma (“galaxy”), and Hinotori (“phoenix”).
A more important distinction between the two agencies’
naming schemes is that where NASDA uses English and
Japanese names as alternatives for its operational satellites,
ISAS uses the English name before launch and then
switches to a Japanese name after launch—but only if the
launch is successful. The ISAS prelaunch name indicates
to which series the craft belongs; for example, Astro-D is
the fourth spacecraft in the Astro- series devoted to astronomical
observations, mainly in the X-ray region of the
spectrum. After its successful launch, Astro-D became
known as Asuka (“flying bird”). On the other hand,
Astro-E never received a Japanese name, because it failed
to reach orbit. To add to the confusion, some ISAS spacecraft
have an alternative postlaunch name, especially if
they have involved collaboration with other nations or
institutions. For example, Asuka (Astro-D) is also known
as ASCA (Advanced Satellite for Cosmology and Astrophysics).
Furthermore, NASDA has recently tended to
move away from the pattern of always providing a Japanese
name. TRMM (Tropical Rainfall Measuring Mission)
and SELENE (Selenological and Engineering Explorer),