Cosmic Revelations: Vera Rubin’s Galaxy Hunt & Lunar Water Secrets

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Language: en

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[Music]


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welcome to Astronomy Daily your source


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for the latest developments in space and


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astronomy news i'm Anna and today we're


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exploring a universe of fascinating


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discoveries that are reshaping our


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understanding of the cosmos on today's


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journey through the stars we'll discover


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how the Vera Rubin Observatory might


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soon triple the number of known


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satellite galaxies orbiting our Milky


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Way potentially revealing hundreds of


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previously hidden cosmic neighbors we'll


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also examine surprising evidence that


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suggests the sun itself may be creating


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water on the lunar surface making this


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vital resource more accessible for


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future moon missions than we ever


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thought possible then we'll look at the


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most precise time pieces ever launched


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into space as the Atomic Clock Ensemble


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finds its new home aboard the


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International Space Station for


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stargazers we have tips on viewing the


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dazzling Sirius this spring as it puts


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on a spectacular light show with


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prismatic colors near the horizon and


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finally we'll uncover why meteor showers


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can be so unpredictable with new


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research suggesting our sun's wobble


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plays a crucial role in how these


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celestial light shows appear in our


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night sky let's get things


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underway our galaxy the Milky Way is


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surrounded by a family of smaller


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satellite galaxies with the large and


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small melanic clouds being the most


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famous members of this cosmic entourage


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currently astronomers have identified


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about 30 of these satellite galaxies but


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exciting new research suggests we're


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just seeing the tip of the celestial


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iceberg the Vera Rubin Observatory with


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its powerful Legacy Survey of Space and


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Time LSST is poised to dramatically


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expand our catalog of these galactic


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companions according to a recent study


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this observatory could potentially


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detect between 89 and 119 satellite


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galaxies when it begins its survey


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operations in a few months effectively


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tripling our current census researchers


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reached this conclusion by creating


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sophisticated simulations based on data


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from the LSST Dark Energy Science


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Collaboration they injected stellar


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population data into simulated surveys


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and tested the observatory's ability to


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recover and identify these faint


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galactic structures these satellite


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galaxies are far more than just


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interesting cosmic neighbors they're


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crucial to understanding how galaxies


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form and evolve in the standard


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cosmological model featuring cold dark


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matter galaxies form as dark matter


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halos merge over time the smallest and


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dimst of these structures are ultra


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faint dwarf galaxies which represent the


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lowest mass dark matter halos that


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contain


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stars finding and studying these elusive


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objects gives astronomers a unique


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window into the fundamental processes


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that shaped our universe many of these


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satellites are so dim and distant that


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they have evaded detection with current


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technology the Vera Rubin Observatory


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with its 8.4 m primary mirror and


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revolutionary 3.2 gapixel camera will


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have the sensitivity to spot these


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cosmic light weights what makes this


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potential discovery particularly


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exciting is that the observatory is


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expected to find satellites at greater


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distances from the Milky Way with lower


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luminosities and fainter surface


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brightness than we've been able to


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detect before essentially revealing an


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entirely new population of galactic


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companions that have remained hidden in


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the cosmic shadows the research behind


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these predictions is fascinating in its


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methodology scientists employed a clever


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technique where they injected simulated


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stars with specific properties into


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existing catalog data essentially


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creating a controlled test environment


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this scientific slight of hand allowed


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them to precisely measure how well the


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Vera Rubin Observatory will be able to


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detect individual stars within these


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distant satellite galaxies one of the


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key challenges in this detection process


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is something astronomers call star


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galaxy separation when observing such


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distant objects it becomes increasingly


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difficult to distinguish between


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individual stars within satellite


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galaxies and the light from distant


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background galaxies that might


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contaminate the data the researchers had


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to develop sophisticated techniques to


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address this critical issue their


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findings revealed that detection


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capability strongly depends on both the


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magnitude of the stars being observed


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and the half-llight radius of their


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parent galaxy for moderately compact


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stellar systems their detection method


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proved 50% efficient at successfully


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identifying dwarf galaxies out to


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approximately 800,000 lightyear from the


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sun what's particularly exciting about


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these upcoming discoveries is that


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they'll help resolve several important


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questions in cosmology current


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observations of satellite galaxies match


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well with predictions from cold dark


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matter models but theorists have long


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suspected our census is woefully


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incomplete the new observations will put


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these models to the test moreover many


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of the ultra faint compact stellar


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systems already discovered have unclear


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origins are they star clusters that


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formed in dwarf galaxies that were later


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disrupted or do they represent an


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extension of the dwarf galaxy population


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into an even smaller and fainter regime


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the wealth of new data from the LSST


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will help astronomers definitively


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answer these questions as one researcher


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noted in the study each newly discovered


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system increases our understanding of


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the Milky Way satellite population


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providing opportunities for unique


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fortuitous discoveries among the most


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extreme stellar systems these findings


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will advance our understanding of galaxy


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formation thresholds reunionization


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processes heavy element production and


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even dark matter


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physics turning our attention to the


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moon now future moon astronauts may have


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access to more water than previously


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believed according to groundbreaking


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research from NASA suggesting the sun


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itself might be continuously


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replenishing water on the lunar surface


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this remarkable finding could


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significantly impact future lunar


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exploration and potential


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habitation the moon unlike Earth lacks a


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protective magnetic field leaving its


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barren surface constantly bombarded by


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energetic particles from the sun


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collectively known as the solar wind


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scientists have long theorized based on


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computer models that this solar wind


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might be creating the ingredients for


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water right on the lunar surface but the


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actual process remained poorly


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understood to investigate this


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phenomenon NASA researchers led by


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planetary scientist Lee Sia Yo at the


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Gddard Space Flight Center conducted a


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meticulous laboratory experiment using


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authentic lunar material the team worked


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with two regalith samples brought back


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to Earth by the Apollo 17 mission one


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from a trench called Wessex Cleft and


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another from the rim of a young crater


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in South Mass the research team first


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prepared these 50-year-old samples by


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baking them overnight in a vacuum


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furnace to remove any terrestrial water


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they might have absorbed since arriving


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on Earth they then constructed a


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specialized apparatus that included a


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vacuum chamber and a tiny particle


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accelerator to recreate lunar conditions


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this allowed them to bombard the samples


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with hydrogen ions for several days


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precisely mimicking how the solar wind


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interacts with the moon's surface it


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took a long time and many iterations to


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design the apparatus components and get


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them all to fit inside explained Jason


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Mlan a research scientist who co-led the


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experiment but it was worth it because


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once we eliminated all possible sources


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of contamination we learned that this


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decades old idea about the solar wind


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turns out to be true


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the results were definitive when


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analyzing how the sample's chemical


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composition changed over time the


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researchers observed a clear drop in


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light signal at exactly the wavelength


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where water absorbs energy near 3


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microns in the infrared spectrum this


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confirmed the formation of hydroxal and


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water molecules directly resulting from


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the simulated solar wind interaction


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what makes this discovery particularly


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exciting is that the process appears to


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be renewable the solar wind continuously


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supplies hydrogen ions that upon


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striking the lunar surface capture


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electrons from lunar materials to become


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hydrogen atoms these newly formed atoms


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then migrate through the dusty regalith


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and bond with oxygen creating both


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hydroxil and water molecules that can


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accumulate across the lunar surface


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especially in permanently shadowed


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regions near the poles


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the experiment revealed a fascinating


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cycle of water formation on the lunar


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surface when the researchers heated


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their lunar samples to approximately


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260° F


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126° temperatures typical of the moon's


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dayside when exposed to direct sunlight


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they observed a significant decrease in


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the water related molecules that had


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formed this wasn't surprising as intense


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heat would naturally cause these


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volatile compounds to break down or


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evaporate but what happened next was


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truly remarkable after heating the


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samples for 24 hours and then allowing


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them to cool for another day the team


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once again exposed them to their


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simulated solar wind the water related


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signatures promptly reappeared in the


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lunar material this cycle of depletion


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and replenishment suggests that the


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solar wind continuously renews small


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amounts of water on the moon's surface


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in an ongoing natural process the


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findings published in JGR Planets


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earlier this year represent a


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significant advancement in our


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understanding of lunar chemistry and


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provide valuable insights for assessing


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the sustainability of water resources on


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our celestial


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neighbor the atomic clock ensemble in


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space known by its acronym ACES has just


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reached a major milestone in space-based


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precision science this cuttingedge


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timekeeping facility developed by the


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European Space Agency has been


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successfully installed on the


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International Space Station marking the


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beginning of an exciting new scientific


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mission aces made its journey to the ISS


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on April 21st 2025 launching aboard a


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SpaceX Falcon 9 rocket from NASA's


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Kennedy Space Center in Florida the


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payload was part of SpaceX's 32nd


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commercial resupply mission just 4 days


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later the station's Canadian robotic arm


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carefully installed the facility on the


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Earth-facing side of ESA's Columbus


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Laboratory where it's set to operate for


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the next 30 months what makes ASES truly


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remarkable is the precision of its


00:10:32.000 --> 00:10:34.389
timekeeping instruments it carries the


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most accurate atomic clocks ever sent


00:10:36.399 --> 00:10:38.790
into space the primary time pieces


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include Pharaoh a cesium based fountain


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clock developed by the French space


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agency CNS and the space hydrogen mer


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built by saffron timing technologies in


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Switzerland these extraordinary clocks


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don't work in isolation they operate


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alongside sophisticated microwave and


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laser link systems that will deliver


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time measurements from orbit with


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unprecedented accuracy this


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configuration allows ACES to establish


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what scientists call a network of clocks


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comparing the most precise time pieces


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both on Earth and in space the system


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was developed through a collaborative


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effort between ESA and European industry


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partners led by Airbus this


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international cooperation has created a


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platform that will not only explore the


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fundamental nature of time but also test


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Einstein's theory of general relativity


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and potentially help redefine the


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scientific standard of the second using


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next generation optical clocks


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the next major step for ASES is its


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first activation which will establish


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communications with ground control this


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will enable telemetry data to flow from


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ASES to Earth and allow engineers to


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send instructions back to the orbiting


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time piece while stabilizing its thermal


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systems in preparation for full clock


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operations


00:11:51.200 --> 00:11:52.949
i'm so excited and proud that our


00:11:52.959 --> 00:11:55.269
incredibly complex and hugely important


00:11:55.279 --> 00:11:57.430
project is now in space after many years


00:11:57.440 --> 00:12:00.230
of hard work said Simon Weinberg ASUS


00:12:00.240 --> 00:12:02.710
project scientist at ESA this is a major


00:12:02.720 --> 00:12:04.389
achievement for ESA and the science


00:12:04.399 --> 00:12:06.310
community and I look forward to seeing


00:12:06.320 --> 00:12:08.629
the results this is ISA's jewel in the


00:12:08.639 --> 00:12:11.430
crown on the International Space Station


00:12:11.440 --> 00:12:13.910
with installation complete ASES now


00:12:13.920 --> 00:12:16.310
faces a six-month commissioning phase


00:12:16.320 --> 00:12:17.990
during which engineers and scientists


00:12:18.000 --> 00:12:19.750
will calibrate the instruments


00:12:19.760 --> 00:12:21.990
thoroughly test the time transfer links


00:12:22.000 --> 00:12:23.750
and characterize the performance of the


00:12:23.760 --> 00:12:26.710
atomic clocks this meticulous setup


00:12:26.720 --> 00:12:28.870
period is crucial to ensure the facility


00:12:28.880 --> 00:12:30.710
can deliver the extraordinary precision


00:12:30.720 --> 00:12:33.030
it was designed for during this


00:12:33.040 --> 00:12:35.190
commissioning period ACES will connect


00:12:35.200 --> 00:12:37.190
with atomic clocks at selected ground


00:12:37.200 --> 00:12:39.590
stations several times daily as it


00:12:39.600 --> 00:12:41.190
orbits Earth on the International Space


00:12:41.200 --> 00:12:43.430
Station the systems capabilities are


00:12:43.440 --> 00:12:45.509
truly remarkable when multiple


00:12:45.519 --> 00:12:47.269
groundbased clocks fall within the same


00:12:47.279 --> 00:12:49.350
field of view for the station such as


00:12:49.360 --> 00:12:51.670
two located within Europe ACES can


00:12:51.680 --> 00:12:54.069
achieve a precision of one part in 10 to


00:12:54.079 --> 00:12:57.430
the power of -17 or about 10 quintilion


00:12:57.440 --> 00:13:00.870
of a second within just a few days this


00:13:00.880 --> 00:13:02.470
level of precision significantly


00:13:02.480 --> 00:13:04.710
outperforms today's systems using


00:13:04.720 --> 00:13:07.190
navigation satellites like GPS by


00:13:07.200 --> 00:13:10.069
between one and two orders of magnitude


00:13:10.079 --> 00:13:12.470
even more impressive is ACS's ability to


00:13:12.480 --> 00:13:15.110
compare distant clocks across continents


00:13:15.120 --> 00:13:17.269
something never directly accomplished at


00:13:17.279 --> 00:13:19.430
this level of accuracy before these


00:13:19.440 --> 00:13:21.110
intercontinental comparisons will take


00:13:21.120 --> 00:13:23.829
approximately a week to complete once


00:13:23.839 --> 00:13:25.910
the commissioning phase concludes and


00:13:25.920 --> 00:13:27.829
the optimal operating parameters for


00:13:27.839 --> 00:13:30.870
Pharaoh are defined ACES will transition


00:13:30.880 --> 00:13:33.269
into its two-year science phase this


00:13:33.279 --> 00:13:35.829
phase consists of 10 planned sessions


00:13:35.839 --> 00:13:38.310
each spanning 25 days of intensive data


00:13:38.320 --> 00:13:40.470
collection the AC science team will


00:13:40.480 --> 00:13:42.470
validate all results before sharing them


00:13:42.480 --> 00:13:45.509
with the global scientific community


00:13:45.519 --> 00:13:47.670
now is an excellent time to view Sirius


00:13:47.680 --> 00:13:49.910
the brightest star in our night sky as


00:13:49.920 --> 00:13:51.910
it puts on a spectacular light show for


00:13:51.920 --> 00:13:54.550
evening stargazers while most of us


00:13:54.560 --> 00:13:57.189
associate Sirius with winter skies it's


00:13:57.199 --> 00:13:58.389
actually during these northern


00:13:58.399 --> 00:14:00.150
hemisphere spring evenings that this


00:14:00.160 --> 00:14:02.470
dazzling stellar jewel delivers its most


00:14:02.480 --> 00:14:03.470
impressive


00:14:03.480 --> 00:14:05.990
performance sirius outshines all other


00:14:06.000 --> 00:14:08.310
stars visible from Earth appearing more


00:14:08.320 --> 00:14:10.230
than twice as bright as Canopus its


00:14:10.240 --> 00:14:12.949
nearest competitor with a magnitude of


00:14:12.959 --> 00:14:15.829
negative 1.45 45 sirius is one of only


00:14:15.839 --> 00:14:17.590
four stars visible from Earth with a


00:14:17.600 --> 00:14:20.230
negative magnitude making it nine times


00:14:20.240 --> 00:14:21.990
more brilliant than a standard first


00:14:22.000 --> 00:14:24.150
magnitude star this exceptional


00:14:24.160 --> 00:14:25.990
brightness can be attributed to its


00:14:26.000 --> 00:14:28.949
relative proximity at just 8.6 lighty


00:14:28.959 --> 00:14:31.350
years away Sirius is the fifth nearest


00:14:31.360 --> 00:14:34.030
star to our solar system the name Sirius


00:14:34.040 --> 00:14:36.470
itself appears to derive from the Greek


00:14:36.480 --> 00:14:39.269
word for sparkling or scorching a


00:14:39.279 --> 00:14:40.870
fitting description for this brilliant


00:14:40.880 --> 00:14:43.430
white star with its distinctive tinge of


00:14:43.440 --> 00:14:45.590
blue but what makes Sirius truly


00:14:45.600 --> 00:14:47.590
remarkable this time of year is its


00:14:47.600 --> 00:14:49.990
captivating scintillation effect when


00:14:50.000 --> 00:14:51.230
viewed near the


00:14:51.240 --> 00:14:54.310
horizon as Sirius sinks toward the west


00:14:54.320 --> 00:14:56.870
southwest horizon in the early evening


00:14:56.880 --> 00:14:58.790
its light must travel through a much


00:14:58.800 --> 00:15:00.870
thicker layer of Earth's atmosphere than


00:15:00.880 --> 00:15:02.949
when it's higher in the sky our


00:15:02.959 --> 00:15:05.189
atmosphere especially near the horizon


00:15:05.199 --> 00:15:07.590
can be particularly turbulent causing


00:15:07.600 --> 00:15:10.470
the starlight to refract and disperse


00:15:10.480 --> 00:15:12.550
for bright stars like Sirius this


00:15:12.560 --> 00:15:14.310
atmospheric turbulence creates a


00:15:14.320 --> 00:15:17.430
mesmerizing display of prismatic colors


00:15:17.440 --> 00:15:19.430
no star rivals Sirius in this


00:15:19.440 --> 00:15:21.990
spectacular light show when observed low


00:15:22.000 --> 00:15:24.430
in the sky Sirius appears to twinkle


00:15:24.440 --> 00:15:26.870
vigorously seemingly splintering into a


00:15:26.880 --> 00:15:29.430
dazzling array of colors from ruby red


00:15:29.440 --> 00:15:31.750
to sapphire blue emerald green to


00:15:31.760 --> 00:15:33.990
amethyst purple the effect is so


00:15:34.000 --> 00:15:35.990
pronounced that casual observers might


00:15:36.000 --> 00:15:38.230
mistake it for a distant aircraft drone


00:15:38.240 --> 00:15:41.590
or even a UFO to witness this celestial


00:15:41.600 --> 00:15:43.910
spectacle at its best find a location


00:15:43.920 --> 00:15:46.150
with a clear unobstructed view of the


00:15:46.160 --> 00:15:49.350
west southwest horizon the most dramatic


00:15:49.360 --> 00:15:51.829
effects occur when Sirius is just 5°


00:15:51.839 --> 00:15:54.150
above the horizon about half the width


00:15:54.160 --> 00:15:57.030
of your fist held at arms length using


00:15:57.040 --> 00:15:59.110
binoculars or a telescope at low power


00:15:59.120 --> 00:16:00.870
can enhance the view making those


00:16:00.880 --> 00:16:03.269
smoldering colors even more striking


00:16:03.279 --> 00:16:05.749
after early May Sirius will rapidly


00:16:05.759 --> 00:16:07.509
descend into the sunset glow and


00:16:07.519 --> 00:16:09.350
disappear from evening visibility around


00:16:09.360 --> 00:16:11.910
May 11th it will remain out of sight for


00:16:11.920 --> 00:16:13.990
about 3 months before reappearing in the


00:16:14.000 --> 00:16:16.310
dawn twilight of mid August heralding


00:16:16.320 --> 00:16:17.990
the approach of the colder nights that


00:16:18.000 --> 00:16:19.069
lie


00:16:19.079 --> 00:16:22.470
ahead time now to solve a mystery new


00:16:22.480 --> 00:16:24.310
research has shed light on a cosmic


00:16:24.320 --> 00:16:26.189
mystery that has long puzzled


00:16:26.199 --> 00:16:28.629
astronomers why are meteor showers so


00:16:28.639 --> 00:16:31.269
unpredictable while casual stargazers


00:16:31.279 --> 00:16:33.110
might be familiar with reliable annual


00:16:33.120 --> 00:16:35.509
displays like the Perciads in August or


00:16:35.519 --> 00:16:37.990
the Geminids in December scientists have


00:16:38.000 --> 00:16:40.470
actually identified approximately 500


00:16:40.480 --> 00:16:42.470
distinct meteor showers throughout


00:16:42.480 --> 00:16:44.870
Earth's year many of these displays seem


00:16:44.880 --> 00:16:46.629
to appear and disappear with little


00:16:46.639 --> 00:16:48.629
warning and now we may finally


00:16:48.639 --> 00:16:51.910
understand why the answer surprisingly


00:16:51.920 --> 00:16:53.990
lies with our sun's subtle movements


00:16:54.000 --> 00:16:56.150
contrary to the simplified models we


00:16:56.160 --> 00:16:58.710
often see our sun doesn't sit fixed at


00:16:58.720 --> 00:17:00.949
the center of the solar system instead


00:17:00.959 --> 00:17:02.949
it wobbles slightly as it orbits around


00:17:02.959 --> 00:17:05.270
the solar systems bearey center the


00:17:05.280 --> 00:17:07.429
common center of mass for all objects in


00:17:07.439 --> 00:17:10.309
our planetary neighborhood researchers


00:17:10.319 --> 00:17:12.630
Stuart Polores and Peter Jennis from the


00:17:12.640 --> 00:17:14.870
SETI Institute discovered that this


00:17:14.880 --> 00:17:16.870
solar wobble dramatically affects the


00:17:16.880 --> 00:17:19.669
paths of meteoroid streams the trails of


00:17:19.679 --> 00:17:22.230
dust and debris left behind by comets as


00:17:22.240 --> 00:17:24.470
they travel through our solar system


00:17:24.480 --> 00:17:26.309
these streams of material can persist


00:17:26.319 --> 00:17:27.829
long after their parent comets have


00:17:27.839 --> 00:17:29.870
departed sometimes lingering for


00:17:29.880 --> 00:17:32.630
centuries when comets approach the sun


00:17:32.640 --> 00:17:34.870
they warm up and release gas and dust


00:17:34.880 --> 00:17:37.270
particles that spread out into space


00:17:37.280 --> 00:17:39.190
these particles form streams that orbit


00:17:39.200 --> 00:17:41.270
through the solar system occasionally


00:17:41.280 --> 00:17:43.669
intersecting with Earth's path but these


00:17:43.679 --> 00:17:45.350
intersections aren't constant or


00:17:45.360 --> 00:17:46.950
predictable without accounting for the


00:17:46.960 --> 00:17:49.430
sun's movement the researchers found


00:17:49.440 --> 00:17:51.590
that the gravitational influence of the


00:17:51.600 --> 00:17:54.310
wobbling sun can either boost or break


00:17:54.320 --> 00:17:56.230
these meteoroid streams as they pass


00:17:56.240 --> 00:17:58.789
near it similar to how spacecraft use


00:17:58.799 --> 00:18:01.510
gravitational slingshots around planets


00:18:01.520 --> 00:18:03.669
this subtle gravitational dance causes


00:18:03.679 --> 00:18:05.750
the meteoroid streams to weave in and


00:18:05.760 --> 00:18:08.870
out of Earth's orbit over time computer


00:18:08.880 --> 00:18:10.710
simulations consistently failed to


00:18:10.720 --> 00:18:12.310
explain the movement of these streams


00:18:12.320 --> 00:18:14.150
until the researchers incorporated the


00:18:14.160 --> 00:18:16.710
sun's wobble into their calculations


00:18:16.720 --> 00:18:18.390
once they included this factor the


00:18:18.400 --> 00:18:19.909
patterns of meteor shower appearances


00:18:19.919 --> 00:18:22.630
and disappearances finally made sense


00:18:22.640 --> 00:18:24.549
the discovery explains why some meteor


00:18:24.559 --> 00:18:26.870
showers appear suddenly dazzle observers


00:18:26.880 --> 00:18:29.110
for a brief period and then vanish for


00:18:29.120 --> 00:18:31.270
decades before appearing again


00:18:31.280 --> 00:18:33.510
it's all a cosmic choreography directed


00:18:33.520 --> 00:18:35.430
by the subtle gravitational influence of


00:18:35.440 --> 00:18:37.990
our wobbling sun the most fascinating


00:18:38.000 --> 00:18:39.830
part of this discovery is the dramatic


00:18:39.840 --> 00:18:41.830
shift in orbital dynamics that occurs


00:18:41.840 --> 00:18:43.750
depending on a meteoroid's distance from


00:18:43.760 --> 00:18:46.390
the sun when meteoroids are traveling


00:18:46.400 --> 00:18:48.630
beyond Jupiter's orbit they're actually


00:18:48.640 --> 00:18:50.789
orbiting the solar systems barry center


00:18:50.799 --> 00:18:53.270
rather than the sun itself this berry


00:18:53.280 --> 00:18:55.350
center essentially the center of mass


00:18:55.360 --> 00:18:57.909
for our entire solar system doesn't


00:18:57.919 --> 00:18:59.990
coincide with the center of the sun but


00:19:00.000 --> 00:19:02.789
instead lies just outside it however


00:19:02.799 --> 00:19:04.950
once these meteoroid streams cross the


00:19:04.960 --> 00:19:06.710
threshold of Jupiter's orbit and move


00:19:06.720 --> 00:19:09.270
inward the sun's immense gravitational


00:19:09.280 --> 00:19:11.510
pole takes over shifting them from


00:19:11.520 --> 00:19:14.230
barentric orbits to heliocentric ones


00:19:14.240 --> 00:19:16.789
meaning they now orbit the sun directly


00:19:16.799 --> 00:19:18.789
this transition creates what researchers


00:19:18.799 --> 00:19:20.870
describe as a step change in the motion


00:19:20.880 --> 00:19:22.710
of these streams


00:19:22.720 --> 00:19:24.630
pillars explained that this shift occurs


00:19:24.640 --> 00:19:26.870
twice during a comet's journey first


00:19:26.880 --> 00:19:28.470
when approaching the inner solar system


00:19:28.480 --> 00:19:31.029
and the sun takes control and again when


00:19:31.039 --> 00:19:32.870
departing as control returns to the


00:19:32.880 --> 00:19:35.990
berry center each transition kicks the


00:19:36.000 --> 00:19:38.150
inclination and orbital node by a small


00:19:38.160 --> 00:19:40.310
but significant amount altering the


00:19:40.320 --> 00:19:41.990
stream's path in ways that wouldn't be


00:19:42.000 --> 00:19:44.150
apparent if we incorrectly assumed the


00:19:44.160 --> 00:19:47.270
sun remained fixed at the center jupiter


00:19:47.280 --> 00:19:48.950
and Saturn play particularly important


00:19:48.960 --> 00:19:50.950
roles in this dance because their


00:19:50.960 --> 00:19:53.190
massive gravitational influence


00:19:53.200 --> 00:19:55.270
primarily determines the location of the


00:19:55.280 --> 00:19:58.070
solar systems bear center as these gas


00:19:58.080 --> 00:20:00.390
giants orbit Jupiter completing a


00:20:00.400 --> 00:20:02.870
circuit every 12 years and Saturn every


00:20:02.880 --> 00:20:05.029
29 they pull the berry center in


00:20:05.039 --> 00:20:06.870
different directions causing the sun to


00:20:06.880 --> 00:20:08.110
wobble in


00:20:08.120 --> 00:20:10.390
response this celestial mechanism


00:20:10.400 --> 00:20:12.470
explains why some meteor showers appear


00:20:12.480 --> 00:20:15.110
only at specific intervals one shower


00:20:15.120 --> 00:20:17.270
that Jennis predicted and later observed


00:20:17.280 --> 00:20:19.990
in Spain occurs only every 60 years


00:20:20.000 --> 00:20:22.150
precisely when Jupiter and Saturn align


00:20:22.160 --> 00:20:23.830
in positions that nudge a particular


00:20:23.840 --> 00:20:26.110
meteoroid stream across Earth's orbital


00:20:26.120 --> 00:20:29.029
path the entire display lasted just 40


00:20:29.039 --> 00:20:30.789
minutes but produced a bright meteor


00:20:30.799 --> 00:20:33.669
every minute at its peak over longer


00:20:33.679 --> 00:20:35.990
time frames of millennia or more these


00:20:36.000 --> 00:20:37.990
initially narrow streams gradually


00:20:38.000 --> 00:20:40.710
disperse this happens because the stream


00:20:40.720 --> 00:20:42.710
stretches around the sun with different


00:20:42.720 --> 00:20:44.950
meteoroids receiving gravitational kicks


00:20:44.960 --> 00:20:47.190
at slightly different times creating a


00:20:47.200 --> 00:20:49.110
wider range of orbital motions within


00:20:49.120 --> 00:20:51.350
the stream and eventually resulting in


00:20:51.360 --> 00:20:53.190
the more predictable annual meteor


00:20:53.200 --> 00:20:55.470
showers we're familiar with


00:20:55.480 --> 00:20:57.909
today and that concludes today's episode


00:20:57.919 --> 00:21:01.510
of Astronomy Daily i'm Anna your host


00:21:01.520 --> 00:21:03.110
and I want to thank you for joining me


00:21:03.120 --> 00:21:05.110
on this cosmic journey through the


00:21:05.120 --> 00:21:08.310
latest discoveries in our universe as I


00:21:08.320 --> 00:21:10.870
like to say the cosmos never ceases to


00:21:10.880 --> 00:21:13.750
amaze us i'd like to invite you to visit


00:21:13.760 --> 00:21:15.310
our website at


00:21:15.320 --> 00:21:17.350
astronomydaily.io where you can catch up


00:21:17.360 --> 00:21:19.270
on all the latest space and astronomy


00:21:19.280 --> 00:21:21.190
news with our constantly updating news


00:21:21.200 --> 00:21:23.590
feed and listen to all our back episodes


00:21:23.600 --> 00:21:26.070
whenever you like subscribe to the


00:21:26.080 --> 00:21:28.070
podcast via your favorite podcasting


00:21:28.080 --> 00:21:30.870
platform including Apple Podcasts


00:21:30.880 --> 00:21:33.510
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00:21:33.520 --> 00:21:35.669
miss an episode we're bringing you the


00:21:35.679 --> 00:21:38.789
universe one discovery at a time thanks


00:21:38.799 --> 00:21:40.549
for listening and we'll see you next


00:21:40.559 --> 00:21:44.270
time on Astronomy Daily astronomy


00:21:44.280 --> 00:21:47.750
Day stories told


00:21:47.760 --> 00:22:02.119
[Music]