Whirlpools Found on the Sun’s Surface for the First Time

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Good day and welcome to Astronomy Daily.


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I'm Anna


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>> and I'm Avery. It's the weekend rap for


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Saturday the 8th of August and this is


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one of those rare weekends where the sky


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itself is the headline. We are 4 days


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out from a total solar eclipse and the


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peak of the perciads landing on the very


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same night.


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>> We'll get you set for all of that in the


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sky watch at the end. Both hemispheres,


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proper local times, and one eye safety


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rule none of us are allowed to skip. But


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we start where the whole week has


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quietly been pointing at the sun.


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>> Then three stories at the Find the Week.


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A rocket stage that finally hit the


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moon. A 48-year-old spacecraft that just


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bought itself another year of life. And


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the rescue mission that spent the week


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rescuing itself. Let's go.


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>> Here's the question that sounds simple


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and isn't. What does the surface of the


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sun actually look like up close? Not the


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postcard, the fine detail right down at


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the scale where the physics happens.


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This week, for the first time, we got to


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see it. And the answer is it's covered


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in whirlpools.


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>> Whirlpools on the sun.


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>> Tiny ones, some only about 20 km across,


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which on the sun is almost microscopic.


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In a paper published Wednesday in


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Nature, a team led by David Kureds at


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the US National Solar Observatory in


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Hawaii, the biggest solar telescope ever


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built, a 4 m mirror on Haleakala zoomed


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in on the edges of the sun's granules.


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And where earlier telescopes saw a


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smooth, slightly blurry boundary, Inoi


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saw structure curling, breaking,


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wavelike swirls forming and dissipating


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everywhere along the magnetic


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boundaries.


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>> And these have a name. They're not a


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total surprise physically. Right.


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>> Exactly right. And that's what makes it


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satisfying rather than baffling. They're


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called Kelvin Helmholtz instabilities.


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If you've ever watched wind peel the top


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of an ocean wave or seen those rows of


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curling cloud that look like a breaking


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sea in the sky, that's the same effect.


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It happens whenever two fluids slide


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past each other at different speeds.


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Lord Kelvin and Herman Helmholtz


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described the math back around 1870.


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>> So the physics is 150 years old. The


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picture of it on the sun's surface is 4


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days old.


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>> That's the whole story in one line.


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We've seen these swirls in Earth's


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clouds, in the atmospheres of Jupiter


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and Saturn, even hinted at high up in


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the sun's outer corona, but never before


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down on the visible surface, the


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photosphere, where the solar wind and


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all that magnetic energy actually


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originate. The resolution simply wasn't


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there. Inoui changed that.


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>> Walk me through why the surface is the


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important place to catch them. Because


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that's where the sun's magnetic field


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tangles with its boiling convection.


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Picture the granules, those bright cells


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of hot plasma rising, cooling, sinking


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like a pot of porridge on the boil. At


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the edges, flows crash into each other


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and the magnetic field lines get


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squeezed together. Bundle field lines


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tighter and the field gets stronger. The


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stronger field resists the plasma flow.


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And that sudden change in speed is


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exactly the shear you need to set a


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Kelvin Helmholtz vortex spinning.


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>> And they didn't just eyeball it and


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declare victory.


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>> No, this is the part I like. They ran


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the same magnetic region through a


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state-of-the-art physics simulation. A


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model called Morram built purely from


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the laws of physics. No fudging. And the


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simulated sun grew the same swirls in


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the same places with the same shapes.


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observation and theory shaking hands.


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The Max Plank team called the agreement


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remarkable, and that's the word that


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earns this a nature paper. Not we saw


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something odd, but we saw it. We


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understand why. And the model agrees.


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>> So, why should someone with feet firmly


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on the ground care about micro whirlples


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93 million miles away?


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>> Two reasons, and they're both big. The


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first is one of the great unsolved


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puzzles in solar physics. The corona


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problem. The sun's surface is around


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6,000°.


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Its outer atmosphere, the corona, is


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millions of degrees, hundreds of times


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hotter, further away from the heat


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source. That should be impossible. Like


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standing back from a campfire and


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getting warmer, something is carrying


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energy upward and dumping it into the


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corona. And these ubiquitous little


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vortices are a very good candidate for


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part of that pipeline. And the second


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reason is the one that reaches down and


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touches us.


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>> Base weather. Those same swirls could


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feed the buildup of magnetic energy that


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the sun eventually releases as flares


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and coronal mass ejections. The blasts


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of charged particles that when they're


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aimed our way can knock satellites


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about, degrade GPS and stress power


00:05:06.479 --> 00:05:09.510
grids. The next step is to turn pattern


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recognition algorithms loose on long


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runs of enoya data to measure how much


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energy these instabilities actually


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shift. Nail that number and you sharpen


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the models that forecast solar storms,


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>> which is a lovely place to be starting


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an eclipse week. Honestly, everyone's


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about to point their attention at the


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sun anyway.


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>> It really is. For decades, this was a


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prediction on a chalkboard. This week,


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it became a picture. The sun's surface


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isn't a smooth glowing ball. It's a sea


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and it's full of breaking waves.


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>> From the sun to the moon. And to a story


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this show first flagged back in the


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autumn. Early Wednesday morning, a spent


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SpaceX Falcon 9 upper stage slammed into


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the far western edge of the moon near


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Einstein crater at around 2 in the


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morning, US Eastern time.


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>> This is the one astronomer Bill Gray had


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been tracking since April.


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>> The very one. Catalog number 2025-010D,


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roughly four tons of hollow metal about


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12 meters long. It launched in January


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last year, carrying two commercial lunar


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landers, Fireflies Blue Ghost and Ice


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Bas's Resilience under NASA's commercial


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lunar program. Its job done. It was left


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drifting. And for 19 months, sunlight


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and gravity nudged it around cis lunar


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space until the numbers lined up on a


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collision course.


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>> And it hit at genuinely startling speed.


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>> About 5,400 m an hour, seven times the


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speed of sound, releasing energy like


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roughly 3 tons of TNT. The catch for sky


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watchers, it came down on sunlit ground,


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so any flash was washed out by daylight.


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Nobody on Earth got the fireworks.


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>> So, how do we actually confirm it


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happened and see the scar


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>> from orbit? And this is where it gets


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good. NASA's Lunar Reconnaissance


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Orbiter and South Korea's Danuri


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spacecraft are retasking to photograph


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the site because we know almost exactly


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where and when it struck. We get a rare


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before and after. a fresh crater


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expected somewhere between 18 and 30


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meters wide appearing on a patch of moon


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we already had mapped. I'll be honest,


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those highresolution images aren't in


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hand yet. They depend on lighting and


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orbital geometry over the coming weeks,


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but the impact itself is confirmed.


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>> And there's a bigger point sitting


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underneath the spectacle.


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>> There is. This is only the second known


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unintentional lunar impact by a rocket


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stage. The first was a Chinese booster


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back in 2022, but the traffic up there


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is climbing fast and there's still no


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binding rulebook for disposing of


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hardware on these high energy paths.


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SpaceX says this stage was passivated by


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the book and is now working with NASA on


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prevention. Fittingly, the international


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meeting that produced the latest


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recommendations for the moon was held


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right here in Sydney. The


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recommendations are real. The


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requirements aren't there yet. A new


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crater and a nudge to write some rules


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before the next one. Now to the most


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distant good news story you'll hear all


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year. Voyager 2, launched in 1977,


00:08:19.440 --> 00:08:22.710
now more than 21 billion kilometers away


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out in interstellar space, has just been


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given at least another full year of


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science by engineers who can't touch it,


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can't send it apart, and have to wait


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about 19 and a half hours just for a


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command to arrive.


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>> And they've given the maneuver a


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wonderful name.


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>> They're calling it the Big Bang. Here's


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the problem it solves. Voyager runs on


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plutonium radioisotope generators that


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turn heat from decay into electricity.


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And that supply drops by about 4 watts


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every single year. It's a spacecraft


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slowly running out of power. And for


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years, the fix has been to switch


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instruments off one by one. Without


00:09:03.519 --> 00:09:05.829
action, Voyager 2 would have had to shut


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down another of its three remaining


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instruments before the end of this year.


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>> So why Big Bang? What's dramatic about a


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power swap?


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>> Because it all had to happen at once,


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they switched off a set of power- hungry


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devices and swapped in lower power


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alternatives. But the catch is that the


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very same power also produces heat. And


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out there, near absolute zero, if the


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wrong component gets too cold, it


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freezes and dies permanently. You can't


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do it gently, one step at a time. The


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thermal sums only balance if you throw


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the switches simultaneously. As one of


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the engineers put it, they couldn't


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afford to be wrong. And it worked


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exactly to plan.


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>> And Voyager 1 is next in the queue.


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>> It is. The team is stepping through the


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same process on Voyager 1 in the coming


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weeks. And the early tests have gone


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smoothly. Two probes 48 years old, still


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humanity's only instruments physically


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out in interstellar space. kept alive by


00:10:08.320 --> 00:10:10.389
people rewriting how the hardware is


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used from 13 billion miles back. That's


00:10:14.079 --> 00:10:16.470
not a rescue that ends the story. The


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power keeps falling, but it's another


00:10:18.959 --> 00:10:21.030
year of listening to the space between


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the stars.


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>> And now, our running saga of the week,


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the rescue mission that spent the week


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being rescued. You'll remember the


00:10:28.560 --> 00:10:31.590
setup. NASA's Swift Observatory, 22


00:10:31.600 --> 00:10:34.069
years old, a first responder for gamma


00:10:34.079 --> 00:10:36.470
ray burst is sinking. Its orbit is


00:10:36.480 --> 00:10:38.870
decaying and it can't lift itself. And


00:10:38.880 --> 00:10:41.030
without help, it's likely to re-enter


00:10:41.040 --> 00:10:43.269
this springhour time. Once it drops


00:10:43.279 --> 00:10:47.269
below about 300 km, enter link, built at


00:10:47.279 --> 00:10:49.750
extraordinary speed to go up and give


00:10:49.760 --> 00:10:51.030
Swift a boost.


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>> A commercial servicing spacecraft from


00:10:53.360 --> 00:10:55.750
Catalyst Space built clean sheet in


00:10:55.760 --> 00:10:58.230
about 9 months. Launched last month.


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First of its kind, a private robot


00:11:00.640 --> 00:11:02.630
grabbing a government satellite that was


00:11:02.640 --> 00:11:04.949
never designed to be serviced. Except


00:11:04.959 --> 00:11:07.430
that during commissioning, Link itself


00:11:07.440 --> 00:11:11.110
tumbled into a multiaxis spin up to 90°


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a second with two of its three reaction


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wheels out of action and some loss in


00:11:15.760 --> 00:11:18.630
its cold gas thrusters. The rescuer


00:11:18.640 --> 00:11:19.990
needed a rescue.


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>> And this week is where that turned a


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corner.


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>> It genuinely did. Using thruster burns,


00:11:25.600 --> 00:11:27.750
the team has wrestled that spin all the


00:11:27.760 --> 00:11:32.310
way down from 9° a second to 1.47° 47°


00:11:32.320 --> 00:11:34.550
and they're holding it steady there. The


00:11:34.560 --> 00:11:37.190
D-Spin effectively is one. The mission


00:11:37.200 --> 00:11:39.110
has now shifted from a stabilization


00:11:39.120 --> 00:11:41.829
problem to a software one. Because so


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much of the original attitude control


00:11:43.760 --> 00:11:46.230
system is offline, they're preparing a


00:11:46.240 --> 00:11:48.630
major flight software upgrade to restore


00:11:48.640 --> 00:11:51.190
full control using what still works.


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>> And only once that lands can the chase


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actually begin,


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>> right? software update first, then the


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phasing maneuvers to line Link's orbit


00:11:59.680 --> 00:12:02.470
up with Swift, then a rendevous and a


00:12:02.480 --> 00:12:04.949
grapple with its three robotic arms


00:12:04.959 --> 00:12:07.350
targeted around the end of August. If it


00:12:07.360 --> 00:12:09.910
all comes off, Link slowly walks Swift


00:12:09.920 --> 00:12:11.990
back up toward its old orbit over a


00:12:12.000 --> 00:12:14.310
couple of months, then peels away and


00:12:14.320 --> 00:12:17.030
burns up itself. It's down to the wire,


00:12:17.040 --> 00:12:19.269
but a week ago, this looked close to


00:12:19.279 --> 00:12:21.430
lost, and today it looks like a


00:12:21.440 --> 00:12:23.430
spacecraft catching its breath before


00:12:23.440 --> 00:12:25.670
the hardest part. We will absolutely


00:12:25.680 --> 00:12:27.430
keep you posted as that end of August


00:12:27.440 --> 00:12:30.150
window comes up. And so to the sky and


00:12:30.160 --> 00:12:32.470
what a four days we're heading into. On


00:12:32.480 --> 00:12:35.110
Wednesday the 12th of August, two of the


00:12:35.120 --> 00:12:37.750
year's marquee events land together. A


00:12:37.760 --> 00:12:40.470
total solar eclipse and the peak of the


00:12:40.480 --> 00:12:42.230
Perced meteor shower.


00:12:42.240 --> 00:12:43.990
>> Let's be straight with everyone about


00:12:44.000 --> 00:12:46.470
who sees what because this one is


00:12:46.480 --> 00:12:47.829
lopsided.


00:12:47.839 --> 00:12:50.550
>> It is. So let's do it honestly. The


00:12:50.560 --> 00:12:52.790
total eclipse, the full daytime


00:12:52.800 --> 00:12:55.430
darkness, corona blazing spectacle,


00:12:55.440 --> 00:12:57.910
belongs to the far north. The path of


00:12:57.920 --> 00:13:00.310
totality crosses the Arctic, eastern


00:13:00.320 --> 00:13:02.790
Greenland, western Iceland, and clips


00:13:02.800 --> 00:13:04.629
northern Spain, and the very northeast


00:13:04.639 --> 00:13:06.870
of Portugal near sunset. If you're


00:13:06.880 --> 00:13:08.870
anywhere near there, you're in for one


00:13:08.880 --> 00:13:11.430
of the sky's greatest sights, under two


00:13:11.440 --> 00:13:13.829
and a half minutes of it. And for our


00:13:13.839 --> 00:13:15.750
North American listeners, our largest


00:13:15.760 --> 00:13:17.829
audience, the honest picture is a


00:13:17.839 --> 00:13:20.310
partial and only in one corner.


00:13:20.320 --> 00:13:22.629
>> That's right. No part of North America


00:13:22.639 --> 00:13:25.430
sees totality this time. But in the


00:13:25.440 --> 00:13:27.750
afternoon on the 12th, Eastern Canada


00:13:27.760 --> 00:13:29.990
and the northeastern United States get a


00:13:30.000 --> 00:13:32.310
genuine partial. In parts of Atlantic


00:13:32.320 --> 00:13:34.870
Canada, roughly half the sun covered at


00:13:34.880 --> 00:13:37.030
maximum, a smaller bite across New


00:13:37.040 --> 00:13:39.430
England and the Northeast. Further west,


00:13:39.440 --> 00:13:42.389
it fades to little or nothing. If you're


00:13:42.399 --> 00:13:44.550
in that eastern window, check local


00:13:44.560 --> 00:13:46.710
times for your exact town. It's an


00:13:46.720 --> 00:13:48.470
afternoon event. And dig out your


00:13:48.480 --> 00:13:50.069
eclipse glasses.


00:13:50.079 --> 00:13:52.389
>> Which brings us to the rule we never


00:13:52.399 --> 00:13:53.910
ever skip.


00:13:53.920 --> 00:13:56.790
>> The non-negotiable to look at any


00:13:56.800 --> 00:13:59.110
partial phase of the sun safely. You


00:13:59.120 --> 00:14:01.430
need proper solar filters that meet the


00:14:01.440 --> 00:14:04.310
ISO12312-2


00:14:04.320 --> 00:14:07.189
standard, certified eclipse glasses, or


00:14:07.199 --> 00:14:10.310
a safe solar viewer. Ordinary sunglasses


00:14:10.320 --> 00:14:13.030
do not work no matter how dark. Only


00:14:13.040 --> 00:14:14.870
someone standing inside the path of


00:14:14.880 --> 00:14:17.590
totality may remove them and only during


00:14:17.600 --> 00:14:20.230
the brief total phase. Everyone seeing a


00:14:20.240 --> 00:14:22.710
partial, that's all of North America and


00:14:22.720 --> 00:14:25.350
most of Europe, keeps them on the entire


00:14:25.360 --> 00:14:27.910
time. Damage to your eyes is painless


00:14:27.920 --> 00:14:30.949
and permanent. Please don't risk it. And


00:14:30.959 --> 00:14:32.870
if you're nowhere near the track, which


00:14:32.880 --> 00:14:34.389
includes all of us down here in the


00:14:34.399 --> 00:14:37.030
south, NASA streams the whole thing live


00:14:37.040 --> 00:14:40.150
from about a quarter 1 Eastern. Now, the


00:14:40.160 --> 00:14:42.629
Perciads that same night, and here the


00:14:42.639 --> 00:14:44.470
news is good for the northern half of


00:14:44.480 --> 00:14:46.710
the world. The peak lies the night of


00:14:46.720 --> 00:14:49.269
the 12th into the 13th. And this year,


00:14:49.279 --> 00:14:51.509
the peak is essentially moonless. The


00:14:51.519 --> 00:14:54.069
eclipse falls on a new moon, so the sky


00:14:54.079 --> 00:14:56.230
is dark and the faint meteors get their


00:14:56.240 --> 00:14:59.110
moment from the midn latitudes after


00:14:59.120 --> 00:15:01.509
midnight. That's potentially dozens an


00:15:01.519 --> 00:15:04.069
hour under clear skies. North America,


00:15:04.079 --> 00:15:06.710
Europe, this is your gift of the week.


00:15:06.720 --> 00:15:09.030
>> But the Perciads are a northern shower.


00:15:09.040 --> 00:15:10.870
The radiant barely lifts above the


00:15:10.880 --> 00:15:12.870
horizon for those of us down here.


00:15:12.880 --> 00:15:15.509
>> It barely clears it. So from Sydney or


00:15:15.519 --> 00:15:17.990
Akland, you'll catch only a stray few


00:15:18.000 --> 00:15:20.310
low in the north before dawn. Though


00:15:20.320 --> 00:15:22.069
here's what the southern hemisphere


00:15:22.079 --> 00:15:24.069
actually gets, and it's worth setting an


00:15:24.079 --> 00:15:26.790
alarm for. Before sunrise this week, the


00:15:26.800 --> 00:15:29.509
morning sky is stacked. A long line of


00:15:29.519 --> 00:15:32.150
planets, Saturn, Mars, Uranus, and


00:15:32.160 --> 00:15:34.710
Neptune with Jupiter low, and Mercury


00:15:34.720 --> 00:15:37.670
climbing strung across the pre-dawn.


00:15:37.680 --> 00:15:39.750
Venus is your brilliant evening star


00:15:39.760 --> 00:15:42.710
after sunset. And for the patient, comet


00:15:42.720 --> 00:15:45.509
10p Temple 2 is rising late in the


00:15:45.519 --> 00:15:48.150
evening around 9 if you've got


00:15:48.160 --> 00:15:50.550
binoculars and a dark horizon.


00:15:50.560 --> 00:15:52.629
>> So, nobody misses out. North gets the


00:15:52.639 --> 00:15:54.790
eclipse and the meteors. South gets the


00:15:54.800 --> 00:15:57.189
planet parade and a comet. And the live


00:15:57.199 --> 00:15:58.949
stream is there for all of us.


00:15:58.959 --> 00:16:01.910
>> Both hemispheres eyes up all week. Just


00:16:01.920 --> 00:16:03.910
protect them around that sun.


00:16:03.920 --> 00:16:05.910
>> That's the weekend wrap for Saturday the


00:16:05.920 --> 00:16:07.910
8th of August. The sun's hidden


00:16:07.920 --> 00:16:10.790
whirlpools, a fresh crater on the moon,


00:16:10.800 --> 00:16:13.509
Voyager 2's extra year, and a rescue


00:16:13.519 --> 00:16:15.189
mission back on its feet.


00:16:15.199 --> 00:16:16.949
>> We're back with your daily fix on


00:16:16.959 --> 00:16:19.030
Monday. And all week we'll be counting


00:16:19.040 --> 00:16:20.870
down to that eclipse and perced


00:16:20.880 --> 00:16:23.269
Wednesday. Find the fullback catalog,


00:16:23.279 --> 00:16:25.430
the newsfeed, and the newsletter at


00:16:25.440 --> 00:16:27.509
astronomyaily.io


00:16:27.519 --> 00:16:30.710
and say hello at astronomyaily pod.


00:16:30.720 --> 00:16:32.790
>> Until Monday from Anna and me, look


00:16:32.800 --> 00:16:34.629
after those eyes and


00:16:34.639 --> 00:16:46.870
>> clear skies. [music]


00:16:46.880 --> 00:16:55.251
Stories [music] told.


00:16:55.261 --> 00:16:57.281
[music]