Speaker 1: Welcome to brain Stuff, a production of iHeartRadio. Hey brain Stuff,
Speaker 1: Lauren Vogelbomb here with another classic episode of the podcast
Speaker 1: for you. In this one, we talk about Saturn's breathtaking rings,
Speaker 1: how they formed, and why we're actually really lucky to
Speaker 1: be around to see them, because they won't exist for
Speaker 1: very long on the cosmic scale.
Speaker 2: Hey brain Stuff, Lauren vogelbomb Here, humanity exists at a
Speaker 2: very special time in our Solar System's history, the era
Speaker 2: of Saturn's rings. In the next one hundred million years,
Speaker 2: Saturn's rings will completely disappear, and planetary scientists have realized
Speaker 2: that it acquired those rings only very recently. During the
Speaker 2: Cassini mission's final months at Saturn, the NASA spacecraft carried
Speaker 2: out a series of daring orbits through the space between
Speaker 2: the planet's cloud tops and innermost edge of its rings.
Speaker 2: This so called Grand Finale signaled that the end was
Speaker 2: nigh for the probe, and on September fifteenth to tenty seventeen,
Speaker 2: it burned up in the gas giant's atmosphere, bringing a
Speaker 2: spectacular thirteen years of science in Saturn's orbit to a
Speaker 2: poignant close. The spacecraft was low on fuel and to
Speaker 2: avoid an accidental crash into one of Saturn's potentially habitable moons.
Speaker 2: NASA had long ago decided that the best way to
Speaker 2: dispose of the mission was to burn it up in
Speaker 2: Saturn's upper atmosphere. The agency wanted to avoid earthly contamination
Speaker 2: on these pristine alien environments. Before its fiery death, however,
Speaker 2: Cassini took unprecedented measurements of the mysterious ring gap region
Speaker 2: to reveal some surprising ring dynamics. Though mission scientists expected
Speaker 2: to detect some wispy elemental gases in this empty region,
Speaker 2: Cassini's particle instrumentation found a smorgas board of elements and
Speaker 2: molecules raining from the rings down to the planet's atmosphere.
Speaker 2: They estimated around ten tons of material that's about nine
Speaker 2: thousand kilos is falling onto Saturn from the rings per second.
Speaker 2: That means that Saturn's rings will eventually disappear and will
Speaker 2: have existed only for a short blip of s Saturn's
Speaker 2: four billion year life span. So far, researchers have used
Speaker 2: Cassini's ring dives to estimate when Saturn acquired its famous rings.
Speaker 2: When Cassini zipped through Saturn's ring plane. Mission managers allowed
Speaker 2: the planet, its rings and moons to gravitationally tug at
Speaker 2: these speeding spacecraft. These extremely slight tugs resulted in tiny
Speaker 2: changes in the probe's trajectory which could be precisely measured.
Speaker 2: Those changes allowed scientists, too, for the first time, make
Speaker 2: a very good measurement of how much mass is holed
Speaker 2: up in Saturn's rings after analyzing the final set of orbits. However,
Speaker 2: the extent to which Cassini's trajectory was deflected initially didn't
Speaker 2: make sense. It didn't match the predictions by theoretical models.
Speaker 2: It turned out the Cassini's motion was being additionally altered
Speaker 2: by massive flows of material at Saturn's equator, inside its
Speaker 2: thick atmosphere about six thousand miles or nearly ten thousand
Speaker 2: kilometers deep. These massive flows are moving about four percent
Speaker 2: slower than the visible upper atmospheric clouds, causing a gravitational
Speaker 2: anomaly that was and predicted Cassini projects. Scientist Linda Spilker
Speaker 2: of NASA's Jet Propulsion Laboratory said in a statement, the
Speaker 2: discovery of deeply rotating layers is a surprising revelation about
Speaker 2: the internal structure of the planet. The question is what
Speaker 2: causes the more rapidly rotating part of the atmosphere to
Speaker 2: go so deep, and what does that tell us about
Speaker 2: Saturn's interior. However, with this anomaly partially explained, scientists were
Speaker 2: free to measure the gravitational influence of Saturn's rings and
Speaker 2: thus measure their mass. The researchers estimate that the total
Speaker 2: mass of Saturn's rings is approximately forty percent that of
Speaker 2: Saturn's moon Mimas. Considering Mimas is two thousand times smaller
Speaker 2: than Earth's moon, there certainly isn't a lot of material
Speaker 2: in Saturn's rings. Scientists had previously relied on density waves
Speaker 2: or ripples through the rings caused by the motion of
Speaker 2: these sixty two moons in Saturn's orbit to estimate ring mass.
Speaker 2: Although these estimates were also low, astronomers have always assumed
Speaker 2: there was some kind of hidden mass in large blocks
Speaker 2: of material that remained unseen. Now, at the precision measurements
Speaker 2: made by Cassini's final orbits, we know that there is
Speaker 2: no hidden mass. The lower the mass of the rings,
Speaker 2: the younger they are, and because they are predominantly made
Speaker 2: of ice, if they were older, the ring material would
Speaker 2: have become contaminated by interplanetary debris, dulling them, and Saturn's rings,
Speaker 2: as we're acutely aware, are beautifully bright. Previous estimates of
Speaker 2: ring age have been far ranging from four point five
Speaker 2: billion years the leftovers of when Saturn itself was forming,
Speaker 2: to a few tens of million years, But with this
Speaker 2: new finding in hand, it looks like the rings are
Speaker 2: very young, formed less than one hundred million years ago
Speaker 2: and perhaps as recently as ten million years ago. Where
Speaker 2: the rings came from remains more of a mystery. It's
Speaker 2: possible that an icy object from the Kuiper Belt or
Speaker 2: an arrant comet became entwined in Saturn's gravitational field and
Speaker 2: succumbed to the planet's powerful tides, was ripped apart and
Speaker 2: eventually ground down to create the banded rings we know
Speaker 2: and love today. Although Saturn's rings will be gone in
Speaker 2: a hundred million years, it doesn't mean that our Solar
Speaker 2: systems ringed planet days are gone forever. If Saturn can
Speaker 2: create them, there's little reason why Jupiter, Neptune, or Uranus
Speaker 2: can't shred and nice the object create another bright ringed planet.
Speaker 2: Display in the distant future.
Speaker 1: Today's episode is based on the article Saturn's Rings will
Speaker 1: exist for just a blippin time on how stuffworks dot Com,
Speaker 1: written by Ian O'Neill. Brain Stuff is production of iHeartRadio
Speaker 1: in partnership with how Stuffworks dot Com and is produced
Speaker 1: by Tyler Klang. Four more podcasts my heart Radio, visit
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