美国国家公共电台 NPR Juno Spacecraft Reveals Spectacular Cyclones At Jupiter's Poles(在线收听) |
ARI SHAPIRO, HOST: There are cyclones at the poles of Jupiter. That's one of the surprises that NASA is reporting today. The space agency's Juno probe has been orbiting the gas giant since last summer. It's completed six revolutions of the planet so far. NPR science correspondent Joe Palca reports on the illuminating and confusing new findings. JOE PALCA, BYLINE: Planetary scientist Fran Bagenal doesn't mince words. She says the data coming back from Juno are fabulous. FRAN BAGENAL: And they're fabulous because they're not what we expected. PALCA: And what exactly does she mean by that? BAGENAL: If we just saw what we expected it would be ho-hum (ph), ho-hum, that's good. But seeing puzzles and mysteries and getting us all wondering what we're seeing is more exciting. PALCA: Now, some of those puzzles and mysteries are mostly of interest to scientists like Bagenal who have spent their professional lives studying Jupiter. For example, there are spectacular auroras at the poles of Jupiter much more dazzling than the northern lights of Earth. These auroras are caused by energetic particles. Bagenal says there should be strong electrical currents associated with all those particles. BAGENAL: But we haven't detected the magnetic field perturbation associated with them. PALCA: I'm taking her word that that's a surprise. Another puzzle that Juno is supposed to help solve is whether Jupiter has a solid core under all that gas. Jonathan Lunine is a Juno scientist with Cornell University. JONATHAN LUNINE: The early data are suggesting the presence of a core, but not a discrete core. It seems that it's fuzzy. PALCA: Lunine says more data should help provide a more precise understanding than fuzzy. But Lunine says the most visually stunning discoveries from Juno are the giant cyclones at the poles. Ultimately, scientists will want to understand how these cyclones change over time and whether they form differently in the north and south poles. LUNINE: But for now, just to sit back and stare at these images is just a delight to the eye. PALCA: One of the images is on our website if you want to check it out. And details about the scientific results can be found in the journals Science and Geophysical Research Letters. Joe Palca, NPR News.
(SOUNDBITE OF EMANONS' "CALYPSO BOP") |
原文地址:http://www.tingroom.com/lesson/npr2017/5/408984.html |