Episode 100: When Black Holes Beat Galaxies, Rocks Beat Rovers and Planets Smell Terrible

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Kind: captions
Language: en

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Welcome to Astronomy Daily. I'm Anna.


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>> And I'm Avery. You're listening to


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season 5 and today to episode 100.


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>> 100 episodes this season. We should


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probably pause for half a second and


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just notice that.


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>> Half a second starting now.


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>> Done. Back to the universe, which as


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usual hasn't slowed down to let us catch


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our breath.


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>> Not even slightly. Today we have a


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rocket heading to the International


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Space Station literally tonight. A Mars


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rover that accidentally picked up a rock


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and couldn't put it down. A cosmic


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debate that may finally be settled about


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our closest galactic neighbor. And two


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extraordinary findings from the James


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Webb Space Telescope that are rewriting


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the early history of the cosmos.


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>> And we're closing with a planet that's


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we're just going to say it smells like


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rotten eggs. It's a good one.


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>> It really is. Let's go. We're starting


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with news that is happening today, right


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now. In fact, as you're listening to


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this, SpaceX and NASA are targeting


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tonight for the launch of the 34th


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commercial resupply services mission to


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the International Space Station,


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>> CRS 34. And this one's a big cargo run.


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>> It is. A Falcon 9 rocket is standing at


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Space Launch Complex 40 at Cape


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Canaveral. And the launch window opens


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at 7:16 this evening, Eastern time.


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That's 9:16 if you're on the east coast


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of Australia Wednesday morning.


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>> There is always a weather caveat with


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Florida launches.


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>> Always. Forecasters are giving only


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about a 35% chance of favorable


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conditions at liftoff. So there's a real


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possibility it slips to the backup


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window on Wednesday evening. But as of


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right now, the mission is go.


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>> What's on board?


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>> About 6,500 lb of cargo, crew supplies,


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station hardware, and several science


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experiments that are genuinely


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interesting. One investigation involves


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a bone scaffold made from wood that


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researchers hope could lead to new


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treatments for osteoporosis. That's a


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disease that affects bone density, and


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it actually worsens in the lowgravity


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environment of space,


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>> which makes studying it in space


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especially relevant.


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>> Exactly. There's also a study looking at


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how red blood cells and the spleen


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change during extended space flight. And


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my personal favorite, a new instrument


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called Story, the Storm Time O Plus Ring


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Current Imaging Evolution Instrument.


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It'll monitor the charged particle


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environment near Earth, which is a real


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hazard for power grids and satellites


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during solar storms.


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>> The Dragon capsule on this mission is


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flying for the sixth time, and the


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booster will attempt a return to launch


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site landing, which never gets old to


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watch. After launch, Dragon will spend


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about 38 hours in orbit, raising its


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altitude before docking autonomously


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with the Harmony module on Thursday


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morning. We'll follow up on that in


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tomorrow's episode.


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>> From Cape Canaveral to the ISS in under


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2 days, still extraordinary.


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>> Now, Mars and a story that is part


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engineering drama, part slapstick, and


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entirely endearing.


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>> I love this one. NASA's Curiosity Rover,


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which has been rolling across Mars since


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2012, more than 14 years now, recently


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had something happen that had literally


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never happened before in its entire


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mission. It drilled into a rock and the


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rock wouldn't let go.


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>> It just grabbed on and refused to


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release.


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>> On April 25th, Curiosity extended its


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robotic arm and drilled into a rock that


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the team nicknamed Artakama after the


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Chilean desert. When the rover tried to


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retract the arm, the entire rock lifted


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off the Martian surface. It had lodged


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onto the fixed sleeve surrounding the


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drill bit and simply came with it.


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>> How big was this rock?


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>> About 45 cm across at its base, around


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15 cm thick and roughly 13 kg or about 4


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1/2 kg on Mars due to the lower gravity.


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a substantial chunky rock dangling off


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the end of a rover arm 140 million


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kilometers from the nearest mechanic.


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And the solution isn't as simple as just


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shaking it off. Every command you send


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to Curiosity takes up to 30 minutes to


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arrive,


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>> which is what made the next week so


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dramatic. The engineering team spent


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several days trying different


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approaches, repositioning the arm,


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vibrating the drill, trying different


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angles. For days, Atakama refused to


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budge. They even watched the rock slowly


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shed sand as the arm moved, but it


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stayed put. Finally, on May the 1st, the


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team went all in, tilting the drill,


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rotating it, vibrating it, and spinning


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the drill bit simultaneously. They were


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prepared to try multiple rounds. The


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rock came off on the first attempt


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>> and promptly shattered when it hit the


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Martian ground.


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>> At Takama's last stand,


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>> NASA released the full camera sequence


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this week. It's remarkable footage, and


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Curiosity, for its part, is now happily


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back to its regular science operations.


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14 years in, still finding new ways to


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surprise us.


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>> We're going much, much further out now.


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Not Mars, not even our galaxy. We're


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talking about our galaxy's largest


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satellite, the large magalenic cloud,


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>> which you can see beautifully from


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Australia, sitting low in the southern


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sky on a clear night, looking like a


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detached patch of the Milky Way.


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>> And for a long time, astronomers assumed


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it had been orbiting the Milky Way for


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billions of years, making repeated


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passes, coming close, swinging back out,


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a regular visitor. New research


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published this week argues something


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quite different. That this is actually


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the very first time the large magalenic


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cloud has ever approached our galaxy.


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>> A first invol.


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>> Exactly. A team led by Scott Lucini and


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colleagues ran detailed hydrodnamic


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simulations modeling the gas halo


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surrounding both galaxies and compared


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that with ultraviolet observations of


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the gas clouds between them. They found


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the data is consistent only with a first


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pass scenario. If the cloud had been


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here before, the models say the gas halo


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just wouldn't look the way it does.


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>> What does it mean if it's really a first


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time visitor?


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>> It has significant implications for how


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we understand our galaxy's evolution.


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The large maggalenic cloud is enormous.


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It has billions of stars and a mass


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that's roughly 10% of the Milky Way. An


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object that size sweeping through on its


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first close approach causes disruptions.


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It warps our dark matter halo influences


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star formation tugs on the structure of


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the galactic disc. If it's done this


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before, those effects would have played


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out repeatedly. If this is the first


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time, we're watching something quite


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rare.


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>> The team says their simulations provide,


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and I like this phrase, definitive


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evidence. Though they acknowledge there


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are some tensions with other data sets


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that still need to be resolved.


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>> Science is rarely simple, but the weight


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of this evidence is pointing one way.


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The large magalenic cloud is a newcomer


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and it's heading our way.


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>> Nothing to worry about on a human time


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scale, nothing dramatic happens. But on


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cosmic time, fascinating.


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>> Next, time for the James Web Space


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Telescope and the saga of the little red


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dots. We've talked about these before.


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For listeners who haven't heard, give us


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the quick version.


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>> The quick version. When JWST began


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looking at the very early universe,


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galaxies that existed just a few hundred


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million years after the Big Bang, he


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found hundreds of strange, compact,


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faint red objects that nobody expected


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and nobody can fully explain. They


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became known as little red dots. They're


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roughly 12 billion lighty years away.


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They're intensely red. They're tiny and


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they have properties that don't fit


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neatly into any existing category. The


00:08:06.400 --> 00:08:08.629
debate has been raging for years. Are


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they massive star forming regions?


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Ancient black holes and thick dust


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cocoons? An entirely new type of object?


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>> And now there's a new twist.


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>> There is. Astronomers have been studying


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an unusual object that had been sitting


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unnoticed in archival data from NASA's


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Chandra X-ray Observatory for over a


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decade. It's called the X-ray dot


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cataloged as 3DHST-


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AEGIS-12014.


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And it only revealed its significance


00:08:40.640 --> 00:08:43.990
when JWST recently observed the same


00:08:44.000 --> 00:08:46.630
patch of sky and showed that this X-ray


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source is sitting in exactly the same


00:08:48.959 --> 00:08:51.750
location as one of the little red dots.


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>> A 10-year-old clue hiding in plain


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sight. The team led by researchers at


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Princeton believes this X-ray dot may be


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what an older little red dot looks like.


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In the current theory, little red dots


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are young black holes surrounded by


00:09:05.600 --> 00:09:07.350
dense clouds of gas that they're


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consuming. And that gas absorbs the


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X-rays, which is why most little red


00:09:11.760 --> 00:09:14.550
dots don't show up in X-ray surveys. But


00:09:14.560 --> 00:09:17.350
as that gas gets eaten or blown away,


00:09:17.360 --> 00:09:19.829
the X-rays start getting through. So,


00:09:19.839 --> 00:09:21.750
the X-ray dot might be the same type of


00:09:21.760 --> 00:09:24.389
object, just older and less shrouded,


00:09:24.399 --> 00:09:26.389
>> possibly, or it might be something else


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entirely, a black hole wrapped in exotic


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dust never previously observed. The team


00:09:31.920 --> 00:09:34.230
says further observations are needed.


00:09:34.240 --> 00:09:35.910
But either way, it's a piece of the


00:09:35.920 --> 00:09:37.590
puzzle, and it's pointing us toward


00:09:37.600 --> 00:09:39.269
understanding one of the strangest


00:09:39.279 --> 00:09:41.910
populations of objects ever discovered.


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Now, just quickly before we move on to


00:09:44.160 --> 00:09:46.630
our next story, a reminder that our


00:09:46.640 --> 00:09:49.430
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show notes.


00:10:02.480 --> 00:10:04.790
>> Okay, moving on. We're staying with the


00:10:04.800 --> 00:10:06.949
James Webb Space Telescope because it


00:10:06.959 --> 00:10:09.269
keeps delivering. But now we're looking


00:10:09.279 --> 00:10:11.509
at a completely different puzzle. And


00:10:11.519 --> 00:10:13.829
this one was published yesterday.


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>> Hot off the preprint server.


00:10:15.839 --> 00:10:18.470
>> Literally, astronomers have identified


00:10:18.480 --> 00:10:21.670
two early universe galaxies named Cola 1


00:10:21.680 --> 00:10:25.110
and Neppla 4 observed just 800 million


00:10:25.120 --> 00:10:27.509
years after the Big Bang. And here's the


00:10:27.519 --> 00:10:29.829
strange part. Their black holes at the


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centers of these galaxies are between


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400 and 800 times more massive relative


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to their host galaxies than black holes


00:10:37.440 --> 00:10:39.030
in the modern universe.


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>> In the local universe, galaxies like our


00:10:41.360 --> 00:10:43.829
own, the mass of a central black hole is


00:10:43.839 --> 00:10:46.389
typically about a tenth to a half% of


00:10:46.399 --> 00:10:48.710
the total stellar mass of the galaxy.


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These two are nowhere near that ratio.


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Their black holes weigh in at somewhere


00:10:53.519 --> 00:10:57.750
between 170 and 190 million solar


00:10:57.760 --> 00:11:00.069
masses. The galaxies around them are


00:11:00.079 --> 00:11:02.389
comparatively tiny. The black holes


00:11:02.399 --> 00:11:04.870
appear to have grown first and fast


00:11:04.880 --> 00:11:06.630
while their host galaxies were still in


00:11:06.640 --> 00:11:07.590
their infancy.


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>> Which raises the question, how?


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>> That's the core mystery. The standard


00:11:12.000 --> 00:11:14.150
model of galaxy formation says black


00:11:14.160 --> 00:11:16.470
holes and galaxies grow together in a


00:11:16.480 --> 00:11:18.710
kind of feedback loop. The black hole


00:11:18.720 --> 00:11:20.710
influences star formation. Star


00:11:20.720 --> 00:11:23.110
formation influences the black hole.


00:11:23.120 --> 00:11:25.190
These two objects suggest that in the


00:11:25.200 --> 00:11:27.430
very early universe that relationship


00:11:27.440 --> 00:11:29.509
could be inverted. The black hole didn't


00:11:29.519 --> 00:11:32.630
wait. It grew explosively, outpacing its


00:11:32.640 --> 00:11:34.870
own galaxy by a huge margin.


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>> Astronomers have been finding over


00:11:36.640 --> 00:11:38.150
massive black holes in the early


00:11:38.160 --> 00:11:41.269
universe regularly now with JWST. Each


00:11:41.279 --> 00:11:43.269
new example adds weight to the idea that


00:11:43.279 --> 00:11:45.430
our models of galaxy formation in the


00:11:45.440 --> 00:11:47.670
first billion years need significant


00:11:47.680 --> 00:11:50.150
revision. And the early universe keeps


00:11:50.160 --> 00:11:52.630
revealing that it was a far wilder,


00:11:52.640 --> 00:11:54.790
faster, more extreme place than we


00:11:54.800 --> 00:11:57.030
imagined. These are not gentle


00:11:57.040 --> 00:11:59.910
processes. This is cosmic violence at a


00:11:59.920 --> 00:12:01.990
scale that's hard to comprehend.


00:12:02.000 --> 00:12:03.829
>> We're closing today with a planet


00:12:03.839 --> 00:12:06.389
discovery that is genuinely new and


00:12:06.399 --> 00:12:09.030
genuinely strange. Strap in.


00:12:09.040 --> 00:12:11.509
>> The headline said rotten eggs. I want to


00:12:11.519 --> 00:12:13.430
hear about the rotten eggs.


00:12:13.440 --> 00:12:15.670
>> We'll get there. Astronomers have been


00:12:15.680 --> 00:12:20.389
studying an exoplanet called L98-59D.


00:12:20.399 --> 00:12:23.030
It sits just 35 lighty years away in the


00:12:23.040 --> 00:12:25.190
southern constellation Volins,


00:12:25.200 --> 00:12:27.190
practically next door by cosmic


00:12:27.200 --> 00:12:29.350
standards, and it's been in their sights


00:12:29.360 --> 00:12:31.990
for a while. But new research published


00:12:32.000 --> 00:12:34.230
this week in the journal Nature has


00:12:34.240 --> 00:12:37.110
revealed just how unusual it is. This


00:12:37.120 --> 00:12:39.509
planet doesn't fit any existing


00:12:39.519 --> 00:12:40.550
category.


00:12:40.560 --> 00:12:43.030
>> What's it like? Imagine a world where


00:12:43.040 --> 00:12:46.150
the entire surface is an ocean, but not


00:12:46.160 --> 00:12:50.470
water. Molten rock, a global magma ocean


00:12:50.480 --> 00:12:53.269
stretching from pole to pole of silicut


00:12:53.279 --> 00:12:55.190
material heated to temperatures that


00:12:55.200 --> 00:12:58.310
would reduce anything we know to vapor.


00:12:58.320 --> 00:13:01.110
Above this ocean sits a thick, dense


00:13:01.120 --> 00:13:03.430
atmosphere. And that atmosphere is


00:13:03.440 --> 00:13:05.590
loaded with sulfur compounds,


00:13:05.600 --> 00:13:07.750
>> which is where the rotten eggs come in.


00:13:07.760 --> 00:13:10.230
hydrogen sulfide, the same compound


00:13:10.240 --> 00:13:13.030
responsible for that distinctive aroma.


00:13:13.040 --> 00:13:15.670
The atmosphere traps heat so efficiently


00:13:15.680 --> 00:13:17.750
that the magma ocean has been kept


00:13:17.760 --> 00:13:20.230
molten for billions of years. A


00:13:20.240 --> 00:13:22.949
permanent planetwide lava sea with a


00:13:22.959 --> 00:13:25.910
toxic sky above it. The lead researcher,


00:13:25.920 --> 00:13:27.910
Dr. Harrison Nichols from the University


00:13:27.920 --> 00:13:30.629
of Oxford, puts it perfectly. He says,


00:13:30.639 --> 00:13:32.949
"The categories astronomers currently


00:13:32.959 --> 00:13:35.990
use to describe small planets may simply


00:13:36.000 --> 00:13:37.430
be too simple.


00:13:37.440 --> 00:13:39.509
>> How did they figure all of this out? You


00:13:39.519 --> 00:13:41.269
can't exactly send the probe."


00:13:41.279 --> 00:13:43.670
>> Advanced computer modeling combined with


00:13:43.680 --> 00:13:45.750
observational data about the planet's


00:13:45.760 --> 00:13:48.790
mass, size, and density. The planet is


00:13:48.800 --> 00:13:50.710
less dense than we'd expect for its


00:13:50.720 --> 00:13:52.870
size, which gave the team the clue that


00:13:52.880 --> 00:13:54.870
the interior is molten rather than


00:13:54.880 --> 00:13:57.509
solid. The co-author, Professor Raymond


00:13:57.519 --> 00:14:00.069
Pier Humber, described being able to


00:14:00.079 --> 00:14:02.389
reconstruct the hidden interior of a


00:14:02.399 --> 00:14:04.790
planet we will never visit. That's


00:14:04.800 --> 00:14:05.990
extraordinary.


00:14:06.000 --> 00:14:07.990
>> And the question it leaves you with,


00:14:08.000 --> 00:14:09.590
what other kinds of planets are out


00:14:09.600 --> 00:14:11.670
there waiting to be discovered is a


00:14:11.680 --> 00:14:12.629
great one.


00:14:12.639 --> 00:14:15.110
>> L98-59D


00:14:15.120 --> 00:14:17.189
suggests we've barely scratched the


00:14:17.199 --> 00:14:19.990
surface of planetary diversity. Worlds


00:14:20.000 --> 00:14:22.550
with global magma oceans, sulfur


00:14:22.560 --> 00:14:24.629
atmospheres, permanent volcanic


00:14:24.639 --> 00:14:27.590
landscapes, and who knows what else. The


00:14:27.600 --> 00:14:30.230
universe is endlessly creative.


00:14:30.240 --> 00:14:33.110
>> Just maybe don't plan a holiday there.


00:14:33.120 --> 00:14:35.110
>> Before we go, a quick look at the


00:14:35.120 --> 00:14:37.269
southern sky for the coming nights.


00:14:37.279 --> 00:14:39.509
>> May is a spectacular month for sky


00:14:39.519 --> 00:14:41.829
watching from Australia and New Zealand.


00:14:41.839 --> 00:14:44.069
Saturn is well placed in the east before


00:14:44.079 --> 00:14:46.230
midnight, and Jupiter is becoming more


00:14:46.240 --> 00:14:48.949
prominent in the pre-dawn sky. The Milky


00:14:48.959 --> 00:14:51.189
Way is arcing beautifully overhead in


00:14:51.199 --> 00:14:53.189
the evening hours. A perfect time to


00:14:53.199 --> 00:14:55.590
look for the large magalenic cloud and


00:14:55.600 --> 00:14:57.990
small megalic cloud low in the south.


00:14:58.000 --> 00:14:59.670
Just as we discussed today,


00:14:59.680 --> 00:15:02.150
>> a pair of firsttime visitors right there


00:15:02.160 --> 00:15:03.110
above you.


00:15:03.120 --> 00:15:05.829
>> Exactly. And if you're under dark skies,


00:15:05.839 --> 00:15:08.310
the southern Milky Way through Centaurus


00:15:08.320 --> 00:15:10.790
and Krux is extraordinary this time of


00:15:10.800 --> 00:15:11.350
year.


00:15:11.360 --> 00:15:14.150
>> That's everything for episode 100. Thank


00:15:14.160 --> 00:15:16.310
you genuinely for being part of this


00:15:16.320 --> 00:15:19.750
journey. 100 episodes means 100 days of


00:15:19.760 --> 00:15:21.910
choosing to spend a few minutes thinking


00:15:21.920 --> 00:15:24.069
about the universe. And we appreciate


00:15:24.079 --> 00:15:26.069
every one of you who comes back each


00:15:26.079 --> 00:15:28.389
day. If you're enjoying the show, please


00:15:28.399 --> 00:15:30.550
subscribe, leave a review wherever you


00:15:30.560 --> 00:15:32.710
listen, and find us on all the socials


00:15:32.720 --> 00:15:35.590
at astroaily pod. The website is


00:15:35.600 --> 00:15:37.910
astronomyaily.io.


00:15:37.920 --> 00:15:39.670
>> We'll be back tomorrow with the outcome


00:15:39.680 --> 00:15:43.509
of tonight's SpaceX CRS 34 launch and


00:15:43.519 --> 00:15:46.069
whatever else the cosmos has in store.


00:15:46.079 --> 00:15:48.790
from all of us at Astronomy Daily. Keep


00:15:48.800 --> 00:16:00.949
looking up.


00:16:00.959 --> 00:16:04.680
Stories told.