Media
Mindlessness
As the Juno spacecraft was nearing its objective on 4 July after a
five-year flight, the USA Today
online headline was, “Humanity’s First Look at Jupiter and its moons.”
As is so sadly common in the shallow media these days, that headline was
wildly inaccurate. There have been many
missions to Jupiter before this. Galileo
orbited the huge gas giant from 1995 through 2003, for example. Pioneer 10 and 11 flew by in 1973 and 1974,
as did Voyagers 1 and 2 in 1979. Ulysses
took a look in 1992. New Horizons probed
its long “magnetotail” in 2007. We have
of course analyzed the behemoth and its moons in some detail with powerful
scopes like Hubble and Chandra. So we
already have a huge library of Jupiter photos, video, and data.
Juno does own some firsts, however.
It’s the fastest thing man has ever sent into space, doing 165,000 mph
as it approached, and requiring a 30-minute main engine burn to slow down to
orbit velocity. It’s the first to take
up a polar 107-day orbit where it will see spectacular auroras in detail, and it’s
the first to build a global map of the planet’s gigantic gravitational and magnetic
fields. Its trio of 29-foot-long solar
arrays that provide electrical power for its nine different instruments are the
first to be used in such a way so far from our star, where sunlight is only
four percent as bright as on Earth. It’s
built to withstand the intense radiation of a magnetosphere thousands of times
more powerful than ours for as long as possible—an environment so harsh the
visible light camera onboard is expected to fail within only eight orbits, and
its radiometer will be fried within 11 orbits.
Juno will look for water and liquid metallic hydrogen, and study its
fierce winds and the distribution of its mass and its high-energy hydrogen,
helium, oxygen, and sulphur.
Fifth planet from the sun at 484 million miles out (we’re 94 million
miles out), this one was named after the god Jupiter, king of the Roman
pantheon, a notorious seducer of mortal mistresses, who often cloaked himself
in clouds to hide his indiscretions from his wife, Juno.
But now Juno will have her way.
At the end of her 20-month mission of intense scrutiny, she will dive
deep into his raging storms, crushing pressures, and furious temperatures,
seeking to detect the true heart of this by far most muscular planet in our
solar system, and perhaps even learn how he came to be.
Phil
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