August 01, 2011 When it comes to magnetic fields, Jupiter is the
ultimate muscle car. It's endowed with the biggest, brawniest
magnetic field of any planet in the solar system, powered by a
monster engine under the hood. Figuring out how this mighty
engine, or dynamo, works is one goal of NASA's Juno mission,
which is scheduled to begin its five-year, 400-million-mile
(643,737,600- kilometer-mile) voyage to Jupiter this month. Juno
will orbit the planet for about a year, investigating its origin
and evolution. Juno has eight instruments to probe its internal
structure and gravity field, measure water and ammonia in its
atmosphere, map its powerful magnetic field and observe its
intense auroras. The magnetic field studies will be the job of
Juno's twin magnetometers, designed and built at NASA's Goddard
Space Flight Center in Greenbelt, Md. They will measure the
field's magnitude and direction with greater accuracy than any
previous instrument, revealing it for the first time in high-
definition. Read the full