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A gigantic storm has captured scientists' interest for more than a century, but no one's been able to get a really close look at it until now. That's because the storm is on Jupiter. It's better known as Jupiter's Great Red Spot. The close-up look is being provided by NASA's Juno spacecraft, which is orbiting around the planet. NPR science correspondent Joe Palca has this preview of what scientists are hoping to learn about the storm.
JOE PALCA, BYLINE: Juno is flying closer to Jupiter than any space probe has before.
SCOTT BOLTON: Jupiter's stunning when you get near it.
PALCA: Scott Bolton is principal investigator for the Juno mission. He spoke with me from his office at the Southwest Research Institute in San Antonio. Every 53 days, Juno's orbit brings it to within a few thousand miles of Jupiter's cloud tops. Today, the orbit takes it over the Great Red Spot.
BOLTON: We're flying right over it, pretty much.
PALCA: The spot is huge - bigger in diameter than the Earth. Bolton says in addition to taking close-up pictures, one of Juno's instruments can peer through the clouds and see what's underneath the spot - something scientists would dearly like to know.
BOLTON: I mean, it's lasted a really long time. No scientists really understand exactly how that storm was created or why it could last so long. It's possible that the roots are quite deep. And so we'll be able to take a look at that and see what's underneath the cloud tops.
PALCA: This isn't the only time Juno will fly directly over the spot.
BOLTON: Each time, we'll focus on a different kind of science.
PALCA: In a future flyby, Juno will measure the gravity field around the spot. Bolton says there may be something massive below the spot that's contributing to its existence.
BOLTON: Maybe there's a blob going around Jupiter that's underneath the red spot. And we may be able to see that.
PALCA: The blob beneath the spot - that's great.
PALCA: The first photos and data from this latest flyby should arrive on Earth later this week. Joe Palca, NPR News.