Speaker 1: Okay, let's start with a picture. You can barely imagine
something that well, it defies almost every law of expected
cosmic behavior. Picture yourself looking out into the pitch black
of the cosmos, where the combined light of a billion
distant galaxies normally defines the vast scale of reality.
Speaker 2: Right the usual deep sky of view.
Speaker 1: And then, in less time than it takes a fly's
wing to beat, there is a sudden, brilliant, almost apocalyptic
flash of energy that completely outshines every the entire observable
universe for that tiny fraction of a second, and then
just as quickly it's gone vanished.
Speaker 2: Yeah, it sounds completely like science fiction, doesn't it. But
this is the reality of what you could call the
ultimate cosmic disappearing act. And what's really fascinating is that
we're not even talking about visible light here. We are
talking about a terrifyingly powerful, highly directional blast of radio.
Speaker 1: Waves or radio waves exactly.
Speaker 2: These phenomena are known to science as fast radio bursts
or farbs, and honestly, they have been one of the
biggest most persistent mysteries in astrophysics since they were first
stumbled upon.
Speaker 1: That's right, for years. FRBs have been the astronomical equivalent
of a lightning strike. You hear, but you never quite
see where it hit.
Speaker 2: Clearly, that's a good way to put it.
Speaker 1: And our mission today is to take a really deep
dive into the properties, the technology used for their detection,
and crucially, the specific kind of confounding location of the
single brightest cosmic burst ever recorded ah RB float. This
is the legendary RB float. Its discovery and the well
the agonizing attempts to track it down are forcing scientists
to completely rewrite the rule book on what generates these
fleeting super energetic signals.
Speaker 2: Yeah, rewrite or at least add some very complicated chapters.
When we talk about frb's, we are defining them by
their speed and their intensity. They are bright, powerful blasts
of radio waves that truly last just a few milliseconds
ule second. They are by definition instantaneous almost, But that
term instantaneous it doesn't quite capture the scale of the
energy we are discussing here.
Speaker 1: And the scale is where we absolutely have to anchor
this conversation right from the start, because the energy calculation
alone forces us to discard standard stellar physics.
Speaker 2: Almost it really does.
Speaker 1: RB float was so potent so bright that it was
initially flagged as local noise interference. We generate ourselves down here.
Speaker 2: Which is understandable given the brightness.
Speaker 1: But think about this comparison for a moment, because it
really sets the magnitude. One of these bursts in that
tiny fraction of a second is calculated to pump out
more energy than our own sun produces across an entire year,
an entire.
Speaker 2: Year's worth of solar energy, and a flash is just staggering.
Speaker 1: That staggering power is exactly why this specific signal RB
float when from being basically a nuisance data points something
to filter out to the absolute ultimate object of cosmic investigation.
Speaker 2: It's the sheer, physical, well apparent impossibility of that energy output,
combined with the millisecond duration that makes them so compelling.
It just has to be an ultracompact object going through
some kind of ultra violent process. There aren't many alternatives, okay.
Speaker 1: So to really understand the sheer nature of these signals,
especially for listeners who might not be deep into radio astronomy,
we probably need a strong metaphor. You often hear them
describe like a cosmic firework, but I kind of prefer
the idea of a lighthouse.
Speaker 2: Oh, that's a powerful analogy. I like that. Instead of
shining a wide fan of visible light that sweeps across
the sea, these cosmic sources, whatever they turn out to be,
are shooting out a highly directional, intensely focused, and coherent
beam of radio.
Speaker 1: Waves like a laser beam almost but radio sort of.
Speaker 2: Yeah, And that beam is so powerful, so tightly concentrated,
that it remains detectable from well staggering distances. We are
talking about being able to see these signals from several
billions of light years away, effectively halfway across the known
observable universe.
Speaker 1: That's just mind bending. And if that's the general cosmic firework,
our B float is the absolute record breaking grand finale, then.
Speaker 2: Pretty much it stands apart because it is genuinely considered
the brightest FRB ever detected, full stop.
Speaker 1: Right. And you'd think, okay, when you have something that bright,
it should be easy to study, Yeah, easier to see,
easier to pinpoint. But paradoxically, that incredible brightness is exactly
what caused the initial profound confusion.
Speaker 2: That initial confusion is absolutely central to the story. When
the signal from RB float first registered on the detectors.
It didn't trigger the hey cool cosmic event alert. It
triggered the alarm for radio frequency interference RFI RFI. This
RFI flag is the standard noise you expect from much
closer earth bound sources, things like airplanes flying overhead, maybe
satellite telemetry, or perhaps even interference from a cell phone
tower miles away.
Speaker 1: Stuff we make exactly.
Speaker 2: The system is designed really to reject right short pulses
because historically almost all of those pulses are human generated noise.
Speaker 1: And look, when you look at the history of this field,
that default skepticism is entirely rational, isn't it. We have
to remember that cautionary tale from just twenty twenty four.
Speaker 2: Oh yeah, the Relay two incident.
Speaker 1: Astronomers had identified a signal with high confidence. They were
celebrating it as a major FRB discovery from way beyond
the Milky Way galaxy. Major news.
Speaker 2: It was huge at the time, only for months of
meticulous tracing and analysis to reveal the well, frankly heartbreaking truth.
The signal was a rogue transmission, a lingering burst of
telemetry from an old retired NASA satellite called Relay.
Speaker 1: Too, an old satellite.
Speaker 2: YEP. That kind of incident teaches the community a very
deep lesson. When a signal is surprisingly bright, suspiciously short,
and seems almost too.
Speaker 1: Good to be true, assum it's ours.
Speaker 2: The easiest and safest assumption is that it's just nearby
technological noise, not some exotic deep space physics.
Speaker 1: So when this massive power surge that was rb float
came in, the RFI flag was immediately raised. Makes sense.
It was placed in the queue for dismissal.
Speaker 2: Basically the junk pile.
Speaker 1: Yeah, it took a moment of intense targeted scrutiny before
the eureka moment finally hit in March twenty twenty five.
What was the actual analytical trigger what allowed them to
finally say, wait a second, this isn't the satellite.
Speaker 2: The key trigger was the precise analysis of the signal's dispersion.
This is crucial. Unlike man made RFI, which travels through
virtually no intervening space to get to our telescope, right,
it's close by, cosmic radio waves travel through billions of
light years of intergalactic and interstellar plasma thin gas, but
over vast distances. It adds up this plasma slows down
the lower radio frequencies compared to the higher frequencies. It's
like running through tree cole but frequency dependent.
Speaker 1: Ah okay, so different speeds for different frequencies exactly.
Speaker 2: So when the signal hits the detector, the high frequencies
arrive slightly before the low frequencies, creating this telltale sweep
like a downward chirp across the radio spectrum, like.
Speaker 1: A musical node sliding down.
Speaker 2: Precisely, RFI is clean and instantaneous across all frequencies. RB
float had this massive, unmistakable dispersion measure. That spectral suite
proved beyond doubt it had traveled across potentially billions of
light years.
Speaker 1: That distinction, the time delay caused by all that intervening gas,
that's the forensic evidence they needed. That realization confirmed it
was cosmic, absolutely, But it immediately handed scientists the biggest
problem of all, How on earth do you locate something
that only flashed once and then just vanished?
Speaker 2: And this is where the story shifts entirely from you know,
what is it to the agonizing process of where did
it come from? The core challenge posed by rb float
is its single one off nature, right, not a repeater exactly.
In the world of FRBs, many bursts of repeaters. They
might pulse sporadically, maybe over several months, giving astronomers repeated
chances to observe them, refine their coordinates, use multiple telescopes
to triangulate their position, you get more shot.
Speaker 1: But ARB float was the ultimate show off, wasn't it.
It truly just dumped all its energy in one spectacular
millisecond long burst and then silence gone forever, total silence. Scientists.
In the immediate aftermath, they committed hundreds of hours of
follow up observation, pointing the world's best telescopes right back
at that patch of sky, just begging for a glimmer,
a twitch, anything that would confirm the location.
Speaker 2: They caught absolutely nothing. The source was completely dark, and
because that one single data snapshot was all they had,
it made the localization mission exponentially tougher.
Speaker 1: The source material used to that analogy. Yeah, trying to
find the source of RB float is like looking for
a needle in a haystack. But you're saying that's almost
too generous a description of the challenge.
Speaker 2: It really is. The analogy has to be scaled up
to astronomical proportions. The haystack isn't just big, it's the
unimaginable vastness of the universe literally millions, maybe billions of
galaxies potentially containing the source.
Speaker 1: Okay, and the needle.
Speaker 2: The needle disappeared the very moment you started looking for.
It vaporized. So it's not just a game of precision.
It's this astronomical race against time that they had already
lost before they even knew they were running.
Speaker 1: Wow, to grasp the quickness and the required precision. Let's
use that location analogy they mentioned, because it truly brings
home the scale.
Speaker 2: Yeah. The firefly one.
Speaker 1: Yeah, imagine you are standing in New York City, Okay,
and you need to pinpoint the exact location of a
single firefly flashing in a forest somewhere near the Everglades
in Florida.
Speaker 2: Way down there.
Speaker 1: Not only that, but the firefly flashes for just a
single thousandth of a second, one millisecond. The window closes immediately.
You get one look and good luck. And the goal,
astronomically speaking, isn't just to figure out that the firefly
was somewhere in the state of Florida, or even which
town it was near. The goal is to pinpoint the
exact stellar environment exactly. We need to figure out not
only which galaxy it came from, but which specific spiral arm,
which star cluster, maybe even which specific stellar remnant was responsible.
We need to know precisely which branch that firefly was
sitting on when it flashed.
Speaker 2: And that level of precision. Knowing the branch it's fundamentally necessary.
It's not just showing off. Scientists have known about fast
radio bursts since two thousand and seven right for a
while now, and for almost two decades, the exact origin,
the specific mechanism that triggers these blasts remained a total mystery,
stressing the necessity of pinpointing the exact source. Getting that
which branch detail is really the only pathway forward to
uncovering the true cause and the actual physics behind these signals.
Speaker 1: Because if they can link the blast definitively to a
specific stellar type, say a neutron star or maybe a
black hole merger or even a dying giant star, that
link provides the crucial context needed to move past all
the speculation and actually start writing the equations precisely.
Speaker 2: It means moving from just the signal detected in the
void to essentially a cosmic crime scene that can be
investigated forensically. But to do that for a signal that
never repeats, that was the monumental task that required a
huge technological leap.
Speaker 1: So if the challenge was this basically impossible tracking job
based on a single vanishing signal, how do they pull
it off? The answer lies in the incredible detector that
caught the signal in the first place, the Canadian Hydrogen
Intensity Mapping Experiment, known universally as the Trium Telescope SHIMI is.
Speaker 2: It's really a triumph of radical engineering design. If you
picture it, it's not your standard big dish telescope you
might see in movies or documentaries.
Speaker 1: No dish, No.
Speaker 2: It is a massive fixed array of four huge half
pipe shaped antennas located out in the radio quiet zone
of British Columbia, Canada. It looks less like a traditional
telescope and more like a series of sophisticated giant skateboard
ramps just pointed permanently at the sky.
Speaker 1: Like Norman's metal troughs exactly.
Speaker 2: And that fixed design is entirely intentional. It's built to
sweep vast portions of the northern hemisphere sky simultaneously as
the Earth rotates underneath it, gathering just enormous amounts of
data continuously.
Speaker 1: Okay, so it's a survey instrument primarily.
Speaker 2: Yes. The telescope began operating in twenty eighteen, and it's
been wildly successful in simply detecting FRBs since it started.
It's picked up something like four thousand of them.
Speaker 1: Four thousand. That's a massive sample.
Speaker 2: Size, it is, But for years it had a critical
imitation we absolutely need to discuss, which was exactly what
we've been talking about. Localization sheet On was a great
FRB counter, but a famously poor FRB localizer. Its wide
field of view meant it could spot thousands of events,
which is great for statistics, but initially its precision was
just too broad.
Speaker 1: So it came from roughly that huge patch of sky
pretty much.
Speaker 2: If it localized a burst, the coordinates were massive, covering
way too much sky to do effective follow up, and crucially,
the process of even getting those vague coordinates took a
long time. By the time they had a rough idea,
the burst was long gone and deep follow up studies
with other telescopes were basically impossible.
Speaker 1: That distinction counter versus localizer is really key here. But
this is where the major technological turning point comes in,
this big boost and precision. If Gaetam's a designed for
rapid surveying over a huge area, how can it suddenly
pivot to achieve the pin cone accuracy needed for a
single millisecond burst. Was this purely a software trick? Where
did they actually install new hardware?
Speaker 2: It was a combination, but the core enhancement was the
implementation of a separate, specialized processing system working in parallel.
They essentially added kitabilities. Think of them like virtual satellite
dishes linked to the main halfpipes, specifically designed to quickly
process the incoming signal data from the main array and
instantaneously triangulate the source using interferometry.
Speaker 1: AH interferometry using the different arrival times at different points.
Speaker 2: Exactly. Localizing a one off signal is fundamentally different from
localizing a repeating one. You don't have time to wait
for the new pulse to refine the position. You need
simultaneous multipoint measurement across a wide baseline, processed in absolute
real time.
Speaker 1: So this technological upgrade didn't just slightly improve its capability,
it fundamentally changed its job description from being a wide
area counter to being more like an astronomical sniper.
Speaker 2: That's a great way to put it. That new capability
allows chains to do what was previously thought impossible for
this type of wide field instrument. It now localizes bursts
with extreme accuracy, narrowing down the locations not just to
the general galaxy, but to specific stellar environments within that galaxy,
a branch on the tree getting towards the branch. Yes,
and most critically for RB float, the new tech can
localize single, non repeating bursts, which likely represent these destructive
high energy events that we desperately need to understand.
Speaker 1: That is the essential upgrade for the entire field of astrophysics,
isn't it? Being able to catch and pinpoint a one
off event means we can now seriously probe true stellar
catastrop as they happen.
Speaker 2: Right.
Speaker 1: It opens the door to figuring out the actual physical
triggers for these bursts. Are they triggered by stars fading
and collapsing, maybe bizarre magnetic objects like magnetars, or perhaps
something completely unknown, something truly exotic that destroys itself in
the process.
Speaker 2: The precision provides the necessary context, it connects the signal
to the potential source. Without that hyper accurate location data,
all those four thousand bursts to redetected previously were just
tantalizing data points floating in space, statistically interesting but individually frustrating.
Now events like rb float can become detailed crime scenes
that astronomers can investigate using all the other powerful telescopes
in the world.
Speaker 1: Okay, so, armed with this enhanced CHI data and presumably
rapid collaboration with other observatories and organizations, they finally pinpointed
the source of rb float, and the very first finding
was astonishing, not really for its distance in absolute terms,
but for its proximity to us.
Speaker 2: Indeed, that was the first big surprise. It turned out
to be one of the closest fr bees ever detected.
RB float originated only about one hundred and thirty million
light years away. One hundred and thirty million light years,
which sounds immense, of course, but in the grand scheme of.
Speaker 1: Things, right, one hundred thirty million light years is a
distance that is completely incomprehensible to us on a human scale,
yet cosmically speaking, that is practically in our backyard. Our
cosmic neighborhood.
Speaker 2: Absolutely. For context, the entire observable universe is roughly ninety
three billion light years across, so one hundred and thirty
million is right next door. Relatively speaking, It's located in
the direction of the constellation ursa Major the Great.
Speaker 1: Bear, and that proximity is what makes this burst so
incredibly valuable, perhaps even more valuable than its sheer brightness.
Wouldn't you say?
Speaker 2: I think so? Yes, Absolutely, this proximity offers a fantastic
opportunity for detailed forensic study. When something is this close,
the data isn't smeared out or distorted by traveling through
vast stretches of intergalactic gas for billions of years.
Speaker 1: Is cleaner, much cleaner.
Speaker 2: Far more detailed. For instance, astronomers were able to use
the signal properties to estimate how deeply the burst was
embedded in the surrounding gas within its host galaxy. That
gives crucial clues about the source's immediate environment.
Speaker 1: It's local bubble, and what did they find there? Was
it very deep?
Speaker 2: The finding was that it was relatively shallow, meaning the
bursts didn't have to fight its way out of incredibly
dense cloud of gas and dust to reach us. That's
another piece of the puzzle.
Speaker 1: Okay, So let's talk about the astrophysical context of the
location itself. They successfully localized the explosion to one of
the active spiral arms of a particular galaxy. When they
first found this, it must have felt like a perfect
textbook fit for their theories, right, like aha found it?
Speaker 2: Oh? Absolutely initially. Yeah, spiral arms are fundamentally the stellar
nurseries of the universe. They are regions of high density
gas packed with massive stars, and they are constantly giving
birth to new stars. Where the action is exactly this
is where giant stars live fast and die young, often
reaching the end of their lives in spectacular catastrophic fashion.
So it makes perfect logical sense that powerful quick bursts
like FRBs could erupt amidst this ongoing process of star
formation and stellar collapse, where you have all the raw
ingredients for high energy violence.
Speaker 1: It's the highest stakes neighborhood in the galaxy. Really, you
have density, you have intense gravity, you have massive stars
collapsing into tiny ultra dense remnants like neutron stars and
black holes. When they first pinpointed RB flowed there in
a spiral arm. It likely felt like the case was closed. Okay,
FRBs are born from the collapse of massive stars in
these dense spiral arms. Simple.
Speaker 2: It fit the picture beautifully, But as always seems to
happen in astronomy, the solution or the apparent solution, created
an even deeper, more frustrating mystery when they zoomed in
further right.
Speaker 1: So, before RB float, the theories about how FRBs are
produced were quite diverse. They range from stellar collisions, neutron
star mergers, to the exotic physics near black holes, and yes,
for a while, even speculation about highly advanced extraterrestrial intelligence
using powerful cosmic spotlights or beacons.
Speaker 2: The et hypothesis always lingers in the background with these things.
Speaker 1: It does, but a really crucial finding back in twenty
twenty two significantly narrow the field, didn't it. It directly
linked frb's or at least one type of FRB directly
to stellar remnants. That twenty twenty two breakthrough was absolutely key,
and it centered on a repeating burst. Remember, not a
one off like RB flowed. Researchers tracked a radio burst
that was subtly flickering or twinkling as it traveled towards
us scintillation.
Speaker 2: They call it like looking at a star through turbulent
air exactly.
Speaker 1: They followed that flickering clue like breadcrumbs through space.
Speaker 2: And it paid off immensely. They traced that specific repeating
signal back to a spot incredibly close to a known
neutron star. And when we say close, the distance between
the burst source and the remnant was calculated to be
smaller than the distance from say New York City to Singapore.
Speaker 1: That close on the galactic scale, practically.
Speaker 2: Touching, virtually touching, Yes, in galactic terms, that is absolutely
point blank range.
Speaker 1: Wow. So that was the definitive smoking gun evidence they
needed at the time. It proved pretty much absolutely that
FRBs can originate from the magnetosphere, that incredibly powerful twisted
magnetic bubble surrounding a specific type of tiny, ultra dense
star known as a magnetar.
Speaker 2: Right now, just to remind everyone, a magnetar isn't just
any neutron star. It's a specific type that possesses the
most extreme magnetic fields known in the universe, like a
thousand trillion times stronger than Earth's, a thousand times stronger
than even a typical neutron star field strong enough to
tear atoms apart unimaginable forces truly, So the leading theory
then became pretty robust FRBs, or at least the repeating
ones likely come from magnetars, perhaps when they're incredibly stressed.
Crusts crack due to magnetic forces releasing immense amounts of
energy and a focused beam.
Speaker 1: Okay, it makes sense, a violent release from a hypermagnetic object.
Speaker 2: So when RB float, the brightest and closest burst was
located snack dab in the stellar nursery of a spiral arm,
a perfect birthplace for young, potentially newborn magnetars, scientists expected
it to confirm that theory flawlessly. They really expected RB
float to be located right in the middle of the action,
within the densest part of that star.
Speaker 1: Forming clump, the prime real estate for a brand new
magnetar exactly.
Speaker 2: But this is where the RB float enigma just deepens.
Despite the extraordinary precision they achieved, they didn't just localize
it to the spiral arm. They localized it to within
hundreds of light years of specific stellar structures within that arm,
and the precise location revealed something stunning. The explosion happened
near the star forming region, but it was conspicuously not
inside the dense clump of newborn stars. It was offset on.
Speaker 1: The outskirts, not in the downtown core.
Speaker 2: Pretty much on the suburban fringe, you might say, and
that spatial difference is absolutely If the burst was caused
by the immediate catastrophic collapse of a massive star leading
directly to the formation of a magnetar right then and there,
you would absolutely expect that source object to still be
nestled right within the dense, crowded stellar environment where it
was born.
Speaker 1: Because it wouldn't have had time to move far away yet.
Speaker 2: Exactly the time scales involved, astrophysically speaking, don't really allow
it to drift that far out in just the time
since its progenitor star died. So the fact that the
brightest closest burst ever recorded came from the periphery, from
near the nursery but not in it raises massive theoretical questions.
Speaker 1: What are the main implications of finding it on the
outskirts then, rather than right in the core. Does this
location fundamentally rule out the standard immediate stellar collapse creates
magutar creates burst model or does it maybe suggest an
entirely different mechanism is at play.
Speaker 2: It forces us to consider two major possibilities. Really, First,
maybe the source mechanism is fundamentally different than the magnetar
model derived from that twenty twenty two repeating event. Perhaps
RB Float involved an older stellar population or a different
type of stellar interaction altogether that happens away from the
main nurseries.
Speaker 1: Okay, so a different trigger or Second, and this.
Speaker 2: Is perhaps even more thrilling from a dynamics perspective, it
suggests that the source object itself that tiny, dense remnant,
maybe a magma tar, maybe something else might have been
ejected from its birthplace kick out. Yeah, maybe it received
a massive gravitational kick during the chaotic supernova explosion that
formed it, or from an interaction with other stars, and
it was literally flung out of the dense nursery at
high speed. It traveled some distance before it finally flared
up and released the RB float burst we saw.
Speaker 1: Like a cosmic billiard ball shot out of the cluster.
Speaker 2: Something like that. Yeah, it really shows that even with
amazing precision and this incredibly close proximity event like RB float,
the exact origin and nature of these signals remained stubbornly elusive,
or at least more complicated than we thought. We know
which branch it came from, roughly, and we know the
general type of tree it was on, but we still
don't know for sure what was sitting on the branch
or how fast it might have been moving when it snashed.
The mystery continues, hashtags tagged, tash tag outro. But you know,
even with this profound paradox, this new discovery brings us
a significant step closer to unlocking their secrets. It refines
the questions we need to ask, and one of the
biggest mysteries that still needs solving has to do with
their overall behavior pattern.
Speaker 1: Right, that's the remaining dichotomy we touched on earlier. The
two major apparent types of FRBs. Are they repeating like
a kind of cosmic heartbeat that pulses again and again
from the same spot, or are they strictly one off
events like RB float, releasing a single incredibly powerful signal
before going permanently silent.
Speaker 2: Yeah. Determining that pattern or the relationship between the two
is crucial because repeating bursts like the one studied in
twenty twenty two likely come from a living, resilient object
like a spinning magnetar that survives the burst.
Speaker 1: And can do it again, something that recharges.
Speaker 2: Whereas single bursts like RB float seem to be might
come from a truly destructive, one time cataclysmic event like
maybe two neutron stars merging, or the final collapse of
a giant star into a black hole, something that destroys
the engine in the process.
Speaker 1: One is a lighthouse, the other is maybe more like
a bomb.
Speaker 2: That's one way to think about it. Yes, but the
field now is just brimming with promise. Experts are genuinely
convinced that the RB float discovery, especially the localization's success,
is truly only the beginning. It proved that this high
precision localization for even single bursts is now a repeatable capability,
not just a lucky one off accident for the astronomers.
Speaker 1: And the anticipated progress then sounds potentially monumental. We are
expecting to see potentially hundreds of precisely localized FRB events
in the next few years, right, Not just a handful
of singular lucky fines scattered over decades.
Speaker 2: Exactly hundreds. This massive volume of data each pinpointed to
a specific environment, will allow experts to study the full
range of vironments. These signals come from the dense star
forming clusters, the quiet outskirts of galaxies like where RB
float was found, maybe even older, seemingly dead elliptical galaxies
where you wouldn't expect young magnetars. It will give us
a complete, unbiased census of the FRB universe.
Speaker 1: We've moved from just collecting signals to actually doing astronomical
forensic science on the locations.
Speaker 2: That's the leap. And as you mull over the incredible
power and the deep mystery of these vanishing signals, maybe
considered this final provocative thought. What does it truly imply
that the brightest closest cosmic signal ever recorded came from
near but not in the expected birthplace of massive stellar explosions.
It really does raise the unsettling but also exciting possibility
the source mechanism itself might involve objects or physics far
stranger than our current standard magnetar theory suggests, perhaps involving
objects operating just outside the dense stellar nurseries, maybe precisely
because they were violently ejected from the core of their
birth galaxy long ago. The universe still has plenty of
surprises for us.