Artemis 2 Delayed, SpaceX Unveils Stargaze Safety System

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Anna: Welcome to Astronomy Daily, your source for

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the latest space and astronomy news. I'm

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Anna.

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Avery: And I'm Avery. We're here to bring you

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today's cosmic headlines on this Wednesday,

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February 4, 2026.

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Anna: We've got a packed show today with some

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significant developments. NASA's Artemis

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2 mission has hit another speed bump with

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their moon rocket, experiencing some familiar

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issues during testing.

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Avery: SpaceX is making headlines on two fronts

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today. Launching an innovative new space

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safety system while also deal with a

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temporary grounding of their Falcon 9 rocket.

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Anna: The James Webb Space Telescope has spotted

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something extraordinary in the early

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universe. A rare five way galaxy

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merger that's challenging our understanding

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of cosmic evolution.

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Avery: Scientists have finally cracked a 50 year

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mystery about why nearby galaxies seem to be

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fleeing from us. And it involves a massive

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cosmic void.

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Anna: And we'll wrap up with fascinating new

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research on runaway stars. Massive

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stellar objects racing through the Milky Way

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at incre speeds.

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Avery: Let's dive in.

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Anna: Our top story today comes from NASA's Kennedy

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Space center in Florida, where Artemis 2

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mission has been delayed by at least a month

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following issues during a critical wet dress

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rehearsal test.

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Avery: This is the mission that will send four

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astronauts on a flyby of the moon, the first

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crewed lunar mission in over 50 years.

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The crew includes NASA astronauts Reid

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Wiseman, Victor Glover, Christina Koch

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and Canadian Space Agency astronaut Jeremy

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Hansen.

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Anna: So what happened during this test? NASA

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concluded a 49 hour practice countdown on

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Tuesday after loading 700,000

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gallons of liquid hydrogen and liquid oxygen

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into the massive Space Launch System rocket.

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Avery: And early in the tanking process, as we

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reported yesterday, they detected a hydrogen

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leak from the interface that routes cryogenic

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propellant into the rocket's core stage.

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Sound familiar?

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Anna: Unfortunately, yes. These hydrogen leaks

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are reminiscent of the issues that plagued

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the Artemis I launch attempts back in 2022.

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However, there's some good news. They did

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resolve the issue during this test and

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actually achieved full tanking on the first

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try, which NASA considers a tremendous

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success.

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Avery: That's actually quite significant progress.

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The resolution involved stopping the hydrogen

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flow, allowing the interface to warm up so

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the seals could reseat and then adjusting the

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flow of propellant. It worked, but it raised

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concerns about launch day operations.

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Anna: NASA Administrator Jared Isaacman announced

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they're moving off the February launch window

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and targeting March for the earliest possible

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launch. The first opportunity next month is

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Friday, March 6th at

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8:29pm Eastern Time, with the window

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extending through March 11th.

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Avery: There were other issues too, weren't there? I

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read about problems with a valve and some

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communication dropouts.

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Anna: Right, a, uh, valve associated with the Orion

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crew Module hatch pressurization had to be re

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torqued and closeout operations took longer

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than planned. Cold weather affected several

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cameras and other equipment. And perhaps most

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concerning, there were dropouts in audio

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communication channels that have been

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recurring over the past few weeks.

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Avery: What's the crew saying about all this?

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Anna: Commander Reid Wiseman posted on social media

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expressing immense pride in seeing the rocket

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reach 100% fuel loading. Especially

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knowing how challenging the scenario was for

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the launch team. He said they're jumping back

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into training tomorrow to start preparations

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for March.

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Avery: And uh, NASA's planning another wet dress

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rehearsal before the actual launch, correct?

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Anna: That's right. Launch Director Charlie

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Blackwell Thompson confirmed they'll conduct

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another wet dress before proceeding with the

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actual launch. The team needs to fully review

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all the data from this test, mitigate each

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issue and return to testing before setting an

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official target launch date.

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Avery: It's a delay, but safety has to come first,

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especially with a crewed mission to the moon.

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Anna: From the Moon to low Earth orbit.

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SpaceX has just unveiled a

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revolutionary new space safety system called

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stargaze that could fundamentally change

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how we manage the increasingly crowded space

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around our planet.

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Avery: This is fascinating technology, Anna. Uh,

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stargaze is a space situational awareness

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system that uses data From M nearly 30,000

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star trackers across the Starlink satellite

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constellation to continuously monitor objects

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in low Earth orbit.

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Anna: 30,000 star trackers, that's an

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incredible network. And they're detecting

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approximately 30 million transits

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daily across the fleet. That's uh, a several

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order of magnitude increase in detection

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capability compared to conventional ground

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based systems.

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Avery: The need for this kind of system has never

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been more urgent. Practices like leaving

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rocket bodies in LEO operators,

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maneuvering satellites without sharing

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trajectory predictions and anti satellite

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tests have all heightened collision risks.

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Conventional methods typically observe

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objects only a limited number of times per

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day, causing large uncertainties in orbital

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predictions.

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Anna: What makes Stargaze particularly powerful is

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that it provides conjunction screening

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results within minutes compared to the

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current industry standard of several hours.

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That speed can be the difference between a

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successful collision avoidance maneuver and

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a catastrophic impact.

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Avery: Basics actually shared a real world example

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that demonstrates just how critical the

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system is. In late 2025, a

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Starlink satellite encountered a uh,

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conjunction with a third party satellite that

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was performing maneuvers, but whose operator

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wasn't sharing ephemeris data.

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Anna: Ephemeris data, that's the trajectory

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prediction information, right?

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Avery: Exactly. So initially the close approach was

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anticipated to be about 9,000 meters away,

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considered a safe missed distance with zero

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probability of collision. But then just five

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hours before the conjunction, the third party

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satellite performed a maneuver that Collapsed

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the anticipated missed distance to just 60

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meters.

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Anna: 60 meters. That's terrifyingly close

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in space terms.

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Avery: Stargaze quickly detected this maneuver and

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published an updated trajectory to the

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screening platform, generating new

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conjunction data messages that were

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immediately distributed. The Starlink

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satellite was able to react within an hour of

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detecting the maneuver, planning an avoidance

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maneuver to reduce coll back down to zero.

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Anna: And here's the really important part. SpaceX

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is making this data available to all

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satellite operators free of charge. Starting

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this spring, satellite operators who submit

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their own trajectory predictions to the

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platform will receive conjunction data

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messages against stargaze data.

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Avery: It's been in closed beta with over a dozen

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participating satellite operators, and the

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response has been positive. SpaceX is drawing

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a parallel to commercial aviation. There are

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hundreds of thousands of sites daily, but

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they avoid collision broadcaster location and

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flight plans to other aircraft.

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Anna: SpaceX is calling on all spacecraft operators

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to follow this same minimal standard of

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sharing predicted trajectories, Starlink

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updates and shares their ephemeris publicly

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every hour as an example.

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Avery: This is the kind of collaborative approach we

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need. As space becomes more congested, it's

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not just about protecting SpaceX's massive

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constellation. It's about creating a safer

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orbital environment for everyone.

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Anna: Speaking of SpaceX, the company has

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temporarily grounded its Falcon 9 rocket

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following an issue with the upper stage on a

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recent Starlink launch. And the timing

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couldn't be more critical.

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Avery: This happened on Monday, February 2nd. A UH

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Falcon 9 successfully delivered 25

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Starlink satellites to low Earth orbit as

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planned. But after deploying the payloads,

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the rocket's upper stage failed to perform

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its deorbit burn.

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Anna: That deorbit burn is designed to bring the

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spent upper stage down for controlled

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destruction in Earth's atmospher. Without it,

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we have another piece of debris in orbit,

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exactly the kind of problem that stargaze is

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designed to help monitor.

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Avery: The good news is the upper stage did manage

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to passivate itself by venting propellant,

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which lowered its perigee to about

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110km, according to

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satellite tracker Jonathan McDowell. It will

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re enter quickly, but SpaceX.

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Anna: Has grounded the Falcon 9 fleet while teams

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review data to determine root cause and

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corrective actions. And here's where the

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timing gets tricky. The Crew 12 astronaut

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mission to the International Space Station is

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currently scheduled to launch on February 11,

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just eight days from now.

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Avery: Crew 12 is particularly important because it

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will restore the ISS to its normal complement

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of seven crew members. The station has been

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operating with a skeleton crew of just three

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astronauts since January 15, when the four

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crew 11 astronauts departed in the first

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ever medical evacuation from the ISS.

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Anna: NASA Associate Administrator Amit uh

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Kshatriya confirmed that NASA teams from the

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commercial crew program are embedded in the

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investigation alongside SpaceX and the FAA.

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He said they're pressing towards the Crew 12

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window, but the launch will be contingent on

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the return to flight rationale.

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Avery: It's worth noting that the Falcon 9 has an

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incredible safety record. Last year alone, it

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launched a record breaking 165

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times, with all missions successful. Just

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a single mission experienced a significant

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anomaly, a Starlink launch where a booster

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toppled after landing at Sea.

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Anna: That March 3rd incident was traced to a fuel

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leak in one of the booster's nine Merlin

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engines, which led to a fire that weakened a

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landing leg. SpaceX halted launches for a

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week at that time as well.

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Avery: The question now is whether they can resolve

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this upper stage issue quickly enough to meet

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the February 11th crew 12 launch date.

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If not, those three astronauts on the ISS

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will have to wait a bit longer for

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reinforcements from orbital mechanics to.

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Anna: The deepest reaches of space. The James Webb

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Space Telescope has spotted something

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extraordinary. A five way galaxy merger

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in the early universe that's challenging our

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understanding of cosmic evolution.

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Avery: This is remarkable. Anna, uh, the system

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consists of five compact, actively star

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forming galaxies that were emerging when the

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universe was only about 800 million years

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old. That's just 6% of the universe's

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current age.

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Anna: And the level of complexity is what's really

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stunning astronomers. These five galaxies are

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packed into a remarkably small region of

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space. They're separated by only tens of

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thousands of light years. To put that in

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perspective, that's far closer together than

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most neighboring galaxies in the modern

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universe.

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Avery: Dr. Wada H. Yu from Texas A and M University,

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the study's lead author, explained that what

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makes this remarkable is that a merger

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involving such a large number of galaxies was

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not expected so early in the universe's

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history. At that time, galaxy mergers were

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thought to be simpler, usually involving only

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two to three galaxies.

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Anna: But it's not just the number of galaxies

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that's impressive. These five galaxies are

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producing stars at a combined rate of roughly

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250 solar masses per year.

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That's far exceeding typical star formation

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rates for that era.

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Avery: And this rapid stellar production has already

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enriched the system with heavier elements

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like oxygen, materials forged in stellar

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interiors and dispersed through galactic

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interactions. The presence of these elements

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indicates that multiple generations of stars

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had already lived and died.

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Anna: The really fascinating part is that gas

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containing oxygen and hydrogen extends

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beyond the galaxies themselves. This suggests

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that gravitational interactions are pushing

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enriched material into intergalactic space,

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showing how early mergers may have shaped not

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just galaxies, but the larger cosmic

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environment.

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Avery: This discovery really disrupts the standard

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model of galaxy assembly. That model proposes

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a, uh, gradual buildup where small galaxies

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merge over long periods to form larger

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systems. But this five way merger

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demonstrates that complex multi galaxy

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interactions were already underway less than

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a billion years after the Big Bang.

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Anna: Professor Casey Popovich, a UH co author on

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the study, emphasized the implications

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by showing that a complex merger driven

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system exists so early. It tells us

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our theories of how galaxies assemble and

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how quickly they do so need to be updated to

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match reality.

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Avery: This adds to the growing body of evidence

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from JWST that the early universe

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was capable of producing massive mature

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looking galaxies at astonishing speed.

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Matter in the early universe appears to have

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clustered more rapidly and efficiently than

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our simulation suggested.

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Anna: The study was published in Nature Astronomy,

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and it's another example of how JWST

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is fundamentally changing our understanding

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of the cosmos.

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Avery: Sticking with cosmic mysteries, Scientists

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have finally solved a 50 year old puzzle

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about why nearby galaxies appear to be

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fleeing from our own Milky Way. And the

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answer involves a massive cosmic void right

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in our neighborhood.

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Anna: This is one of those mysteries that's been

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nagging at astronomers for decades. Avery

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most large galaxies near the Milky Way, with

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the exception of Andromeda, appear to be

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moving away from us and seem largely

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unaffected by the gravitational pull of our

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Local Group of galaxies.

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Avery: The Local Group being the Milky Way,

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Andromeda and dozens of smaller galaxies.

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So what's the solution?

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Anna: Led by Ewood Wempe at the Captain Institute

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in Gronigan, an international research team

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used advanced computer simulations and

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discovered that matter just beyond the Local

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Group forms a broad flat

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structure stretching tens of millions of

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light years across. And here's the

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vast empty regions lie above and

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below this structure.

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Avery: So we're basically living on a cosmic pancake

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surrounded by voids.

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Anna: That's actually a pretty good analogy. This

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flat distribution of matter is the only way

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to accurately account for both the combined

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mass of the Milky Way and Andromeda and

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unexpected motions of nearby galaxies.

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Avery: But how does this flat structure explain why

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galaxies are moving away from us?

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Anna: It comes down to the Local Void, a

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vast empty region discovered back in

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1987 by Brent Tully and Rick

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Fisher. The Local void extends

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approximately 60 megaparsecs, or

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about 200 million light years. Beginning

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at the edge of the Local.

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Avery: Group, The Local Void is growing because

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there's very little matter inside it to exert

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gravitational pull. Our Milky Way sits in

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what's called the Local Sheet, a flat array

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of galaxies that, um, bounds the void. And

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this Local Sheet is Rushing away from the

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void's center at 260 kilometers

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per second.

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Anna: How fast is that affecting the Milky Way?

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Avery: The Milky Way's velocity away from the local

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void is 970,000

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kilometers per hour. That's 600,000

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miles per hour. It's astonishingly fast.

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Anna: So the new simulations show that this hidden

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geometry, the flat plane of dark matter

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beyond the Local Group, with voids above and

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below, is what's driving these galactic

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motions.

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Avery: Exactly. When researchers included this

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configuration in their simulations, they

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closely matched the observed positions and

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speeds of nearby galaxies. It provides a

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coherent explanation for motions that have

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puzzled astronomers for half a century.

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Anna: This is connected to research about the

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Hubble tension, too, isn't it? The

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discrepancy in measurements of the universe's

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expansion rate?

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Avery: That's right. Some researchers have proposed

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that if we're inside a large local void, it

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could affect how we measure cosmic expansion,

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making the local universe appear to be

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expanding faster than it actually is. Though

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that particular idea remains controversial

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and needs more evidence.

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Anna: What's remarkable is that we're learning Our

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immediate cosmic neighborhood is far more

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structured and dynamic than we previously

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understood. We're not just floating in a

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uniform sea of galaxies. We're on a sheet

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of matter bordering a massive void.

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Avery: And that void is shaping our galaxy's journey

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through space in fundamental ways.

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Anna: For our final story today, we're turning to

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some of the fastest objects in our galaxy,

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Runaway stars that are racing through the

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Milky Way at incredible speeds.

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Avery: Researchers from institutes across Spain have

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just completed the most extensive

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observational study to date of these stellar

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speedsters, analyzing 214 O

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type stars, the brightest and most massive

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class of stars in our galaxy.

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Anna: These aren't just fast moving stars, Avery.

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We're talking about stars with velocities

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that often exceed 700 kilometers per

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second. That's fast enough to escape the

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Milky Way's gravity entirely.

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Avery: The term runaway stars was first used back

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in the early 1960s by Dutch astronomer

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Adrian Blau. He observed stars moving at

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unusually high speeds and proposed they

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originated in binary systems and were

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ejected when the companion star collapsed and

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exploded in a supernova.

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Anna: By 2005, astronomers discovered even

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faster runaway stars, Leading to the

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designation hypervelocity stars. These

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objects are fascinating because of the

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influence they have on galactic evolution.

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Avery: By escaping their systems of origin, these

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stars irradiate gas and dust in the

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interstellar medium, eventually seeding it

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with heavy elements after they go supernova.

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This affects how future stars and planets

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will form.

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Anna: So what did this new study reveal? The team

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00:17:40.040 --> 00:17:42.480
used data from ESA's Gaia

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00:17:42.480 --> 00:17:45.000
observatory and the IACOB

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00:17:45.000 --> 00:17:47.600
Spectroscopic Database to analyze these

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214o type stars.

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Avery: They found that most runaway stars rotate

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slowly, while those that rotate faster are

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more likely to be linked to supernova

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explosions in binary systems. And here's an

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00:17:59.970 --> 00:18:02.250
interesting finding. The highest velocity

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stars tend to be single, suggesting they were

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ejected from young clusters through

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gravitational interactions.

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Anna: So there are actually two different

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mechanisms creating runaway stars.

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Avery: Exactly. Some are explosively ejected by

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supernovae in binary systems, while others

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are gravitationally ejected from close

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encounters with star clusters. The study

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helps clarify the relative contributions of

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these two mechanisms. Lead author

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Marcro Castrillo, now at the European

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Southern Observatory, called this the most

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comprehensive observational study of its kind

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in the Milky Way. By combining information on

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rotation and binarity, they're providing

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unprecedented constraints on how these

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runaway stars are formed.

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Anna: The team also identified 12 runaway

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binary systems, including three X ray

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binary sources that contain neutron stars or

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black holes, and three additional systems

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that are likely candidates for hosting black

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holes.

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Avery: Perhaps the strongest evidence for multiple

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ejection mechanisms was Virtually

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no stars in the study exhibited both high

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velocities and rapid rotation. If all

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runaway stars came from the same process,

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you'd expect to see some with both

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characteristics.

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Anna: Future Gaia data releases and ongoing

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spectroscopic studies will help astronomers

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trace these stars back to their birthplaces

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within the Milky Way, which will confirm

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which mechanism was responsible in each case.

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Avery: And there might be another fascinating angle

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to this research. Understanding these systems

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00:19:30.750 --> 00:19:32.870
could shed light on another role they may

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play in galactic evolution, potentially

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distributing the basic ingredients of life

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throughout the Milky Way as they.

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Anna: Travel cosmic messengers carrying the seeds

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of life across the galaxy. That's a beautiful

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thought to end on.

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Avery: And that wraps up today's episode of

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astronomy daily.

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Anna: From NASA's moon mission delays to SpaceX's

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new safety innovations, from ancient galaxy

501
00:19:54.400 --> 00:19:56.400
mergers to mysteries in our cosmic

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neighborhood, it's been quite a journey

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through the cosmos today.

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Avery: Thanks for joining us. For more space news,

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00:20:02.120 --> 00:20:05.080
visit our website at astronomydaily IO

506
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where you can explore our full archive and

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00:20:07.240 --> 00:20:08.880
stay updated on the latest cosmic

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00:20:08.880 --> 00:20:09.480
discoveries.

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Anna: You can also find us on social media

510
00:20:11.800 --> 00:20:14.280
astrodaily POD across all major

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00:20:14.280 --> 00:20:16.920
platforms. Until next time, keep looking up.