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SCIENCEWednesday 28 October
Spacecraft diving deep into Saturn moon’s erupting water jet
MARCIA DUNN This July 27, 2015 photo made by the Cassini spacecraft shows the moon Enceladus orbiting the Spilker expects it will take
AP Aerospace Writer planet Saturn. a week to get a quick look
CAPE CANAVERAL, Florida at the scientific data and
(AP) — The Cassini space- Associated Press many more weeks for a
craft is about to get an icy proper analysis.
shower as it orbits Saturn. ter’s moons, Europa, Gan- one day live ourselves.” ocean floor. That, in turn, Close-up pictures of Ence-
On Wednesday, Cassini will ymede and Callisto; and Researchers are eager would help characterize ladus should be ready
storm through a jet of water possibly dwarf planets Pluto to nail down the chemi- the potential for life in this much sooner. Cassini will
vapor and frozen particles and Ceres, among others. cal makeup of Enceladus’ slightly salty ocean. snap pictures of Enceladus
erupting from the south “These are worlds with plumes. They also hope to If life exists — and more before, during and after
pole of Enceladus, one of huge bodies of liquid wa- confirm whether the erup- missions would be needed the close encounter. The
Saturn’s many moons. The ter underneath their sur- tions are tight columns for confirmation — it might images will be smeared be-
spacecraft will zoom within faces, bodies with great or curtains of jets running range from microscopic al- cause of Cassini’s speed,
30 miles (50 kilometers) of potential to provide oa- along fractures in the south gae to little fish, the scien- but the team hopes to re-
the pole, providing the best ses for life throughout our pole. tists said. move the blurs and have
sampling yet of its under- solar system,” Niebur said In particular, the space- The action unfolds late some dramatic shots by
ground ocean. Monday. “It’s a journey in craft will be looking to iden- Wednesday morning East- Thursday night or Friday.
Cassini will be traveling understanding about what tify hydrogen molecules in ern Time; it will take several Saturnshine — akin to our
19,000 mph (30,580 kph), so makes a world habitable the plume, which would hours to confirm success moonshine — will provide
it should take just an instant and where we might find help quantify hydrothermal and start returning the in- the only lighting for the
to penetrate the plume. life, and where we might activity occurring on the formation. cameras.
A global liquid ocean is This will be the 21st flyby of
believed to exist beneath Enceladus by Cassini. “It’s
the frozen crust of 300-mile not our last, but arguably
(500-kilometer)-wide Ence- this one is going to be our
ladus. Wednesday’s dive most dramatic,” said proj-
will be the deepest one ect manager Earl Maize.
yet through the continuous Cassini has come closer
plumes, making the enter- to Enceladus — skimming
prise a bit riskier than usual. 15½ miles (25 kilometers)
Launched in 1997, Cas- above the surface in 2008
sini is not equipped to de- — but never dipped so low
tect life, but scientists hope through a plume.
Wednesday’s flyby will pro- Scientists were tempted to
vide clues as to the possibil- fly even lower Wednesday,
ity of it. but did not want to waste
NASA program scien- fuel. Cassini’s orbit around
tist Curt Niebur considers Saturn will not be disturbed
Wednesday’s feat “a very by the plume penetration,
big step in a new era of ex- they asserted. The U.S.-
ploring ocean worlds in our European spacecraft has
solar system.” two years of life remain-
Other probable extraterres- ing before it plunges into
trial ocean worlds: Saturn’s Saturn’s atmosphere and
largest moon, Titan; Jupi- vaporizes.q
