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

Space Shuttle Main Engine. With a bottle of just 3 kg of
helium as plasma fuel, the magnetic bubble could be
operated for three months—the size of the bubble growing
and shrinking in response to changes in the solar wind.
Calculations have shown that there is enough power in
the solar wind to accelerate a 136-kg space probe to speeds
of up to 80 km/s, or 6.9 million km/day. By contrast, the
Space Shuttle travels at a mere 7.7 km/s, or 688,000
km/day. If launched by 2003, an M2P2 spacecraft could
reach the heliopause (where the solar wind runs into the
interstellar wind) by 2013—about six years ahead of Voyager
1, which was launched in 1977.
MABES (Magnetic Bearing Satellite)
A Japanese satellite, launched by NASDA (National
Space Development Agency), that carried an experiment
on the levitation of a magnetic bearing flywheel under
Mach number 251
M2 The M2-F2 lifting body returns to the Dryden Flight Research Center, Edwards, California, flanked by an F-104 chase plane. NASA
zero-g. It was also known by its national name of Jindai
(“cherry tree”).
Launch
Date: August 12, 1986
Vehicle: H-1
Site: Tanegashima
Orbit: 1,483 × 1,604 km × 50.0°
Mach number
A unit of speed, named after the Austrian physicist Ernst
Mach (1838–1916), equal to the ratio of the speed of a
moving object to the speed of sound in the surrounding
medium under ambient conditions. Mach 1 under standard
conditions at sea level is 1,218 km/hr (761 mph); it
decreases with altitude.