Anna: Hey, everyone, welcome back to Astronomy
AstroDailyPod. And if it's the weekend where
you are, welcome to a slightly different
edition of the show.
Avery: This is the weekend wrap. Same show, same,
uh, us, same runtime. But on the weekend,
we're doing things a little differently. One
fresh leap storey you haven't heard from us
yet. And then we round up the big storeys
from the week. In case you missed any of
them,
Anna: it's Saturday, August 15th, series five,
episode 168. And it has
genuinely been one of the biggest weeks we've
covered in a while. Total eclipse, triple
black holes. A black hole hiding inside a
star. A rocket possibly lost at sea.
So today we're going to do two things.
Avery: First, a brand new storey that landed just
yesterday. Physicists may have finally
confirmed something WERNER Heisenberg
predicted 90 years ago about empty space
not actually being empty, which is
Anna: a great one to lead with because it's the
kind of storey that would have been our
Tuesday or Wednesday main storey any other
week. It's just that this week had a lot of
competition.
Avery: Then we're going to run back through the week
an update on Starship, which we told you
Monday might be lost at sea. The black hole
star we covered yesterday. Tuesday's eclipse
and Virgin Galactic's rough few days.
Anna: Lots to get through. Let's get into it.
Okay, so this storey starts in
1936, which is a very unusual
place for us to start.
Avery: Very unusual. Take us back.
Anna: So, in 1936, the physicist Werner
Heisenberg and his student Hans Euler
proposed something that sounds like science
fiction. That empty space isn't actually
empty. That what looks like a vacuum is
really the simmering sea of virtual
particles, electrons and positrons,
flickering in and out of existence for
fractions of a second.
Avery: Which already sounds made up.
Anna: It does, but it follows from quantum theory.
And here's the testable prediction that came
out of it. If you put that empty space
inside an extraordinarily strong magnetic
field, light passing through it should get
polarised in a specific direction, an effect
called vacuum birefringence. Basically,
the vacuum itself starts behaving a bit like
a lens.
Avery: And the problem, I'm guessing, is that
nobody's ever been able to build a magnetic
field strong enough to actually test that.
Anna: Exactly the problem. We're talking about a
magnetic field more than 100 million
times stronger than anything we've ever
produced on earth. So for 90 years, this has
just sat there as an untested prediction of
Avery: quantum electrodynamics, which is where the
magnetar
Anna: Comes in right, because it turns out the
universe has already built the lab we needed.
There's a magnetar out there, a dead star
called 1E1547
5408. Thousands of
light years away. And its magnetic field is
easily strong enough. A team led by Rachel
Stewart, a, uh, physics grad student at
George Washington University, used NASA's
IXPE spacecraft, that's the
Imaging X Ray Polarimetry Explorer, to
cheque.
Avery: And IXPE's whole job is measuring
polarisation.
Anna: That's exactly its job. It launched in
2021 specifically to measure how
polarised high energy X rays are.
Stewart's team pointed it at this magnetar in
March and April of last year and backed that
up with observations. The International Space
Station, Australia's Murrayang Radio
Telescope and the South African Radio
Astronomy Observatory.
Avery: So what did they actually find?
Anna: Two things that together made a pretty
compelling case. First, the X rays
coming off this magnetar were almost three
times more polarised than standard models of
a neutron star's surface could explain on
their own. Second, and um, this is the
clincher, the direction of that polarisation
lined up with the star's magnetic field
and matched the pattern they were already
seeing in its radio waves.
Avery: So it's not just more polarised than
expected, it's polarised in exactly the
direction the Heisenberg Euler prediction
says it should be.
Anna: Exactly. Put those two things together and
vacuum by refringence becomes basically the
only explanation left standing.
Avery: 90 years is a long time to wait for a
callback, really is.
Anna: And Stuart had a nice line about what this
actually means for how we use objects like
this. She said we're not just studying
astronomical objects anymore, we're using
them to test the laws of nature.
Avery: That's a good way to put it. The magnetar
isn't really the subject of the study, it's
the equipment.
Anna: Right. It's a 100 million times stronger
than Earth's best particle physics lab that
just happens to be sitting out there
thousands of light years away. One of the co
authors, Marcus Lower at Swinburne University
in Australia, put some scale on that. He
said detecting vacuum birefringence
requires a magnetic field over a hundred
million times stronger than any we've ever
made on Earth.
Avery: So there's no version of this experiment that
ever happens in a lab. You need a magnetar
or nothing, nothing
Anna: else will do it. And I liked Lower's other
quote because it's a nice reminder of what a
confirmation result like this actually feels
like for physicists he said it's a bit of a
relief because it means that our theories
still work and there's nothing
Avery: broken with physics, which is honestly kind
of funny. The good outcome here is boring.
Nothing broke, right.
Anna: The exciting result would have been actually
quantum electrodynamics is wrong and everyone
would have had a much more interesting week
and a much worse year. This is the
quietly satisfying outcome. Instead, a 90
year old prediction just got its first real
observational backing.
Avery: Where does this go next? Is this case closed
or is there more confirmation needed?
Anna: More confirmation is very much still wanted.
This is a strong first detection, not the
last word. There's a Future mission called
GoSox that's specifically designed to chase
this effect further and nail it down with
more precision. But for now, this is the
strongest evidence anyone's produced that the
vacuum genuinely behaves the way Heisenberg
and Euler said it would back in 1936.
Avery: And just to place it, this research was
published August 5th in Nature, so it's had a
couple of weeks to circulate before really
breaking into wider coverage
Anna: this week, which happens a lot with these
physics results. The paper drops and then it
takes a beat for people to fully appreciate
what it means. But once you explain this
confirms space itself isn't empty, it
tends to land.
Avery: It's a great one to kick off the weekend with
genuinely new physics, using the universe as
the lab nobody could ever build.
Anna: All right, on to the recap. It has been an
absolutely stacked week, so let's go roughly
in the order it happened, starting with
Monday.
Avery: Monday we told you SpaceX's Starship might be
lost at sea. So let's start there with an
update, because it's been hanging in limbo
all week.
Anna: Quick recap for anyone who missed Monday.
This goes Back to Flight 13, which launched
July 24. The upper stage, Ship
40 did something no starship upper stage
had ever done before. It survived a
soft splashdown in the Indian Ocean off
Western Australia, completely intact,
Avery: which was actually the good news storey
originally.
Anna: It really was. SpaceX started towing it
towards shore in Australia, and for a few
days it looked like they might genuinely
bring an intact Upper Stage home for the
first time. But the weather didn't cooperate.
Seas got rougher, conditions kept
deteriorating, and on August 7th, Elon
Musk gave the update. We led Monday's episode
with. He said ship recovery is not looking
good right now.
Avery: And, um, where does that stand now, nearly a
week later?
Anna: Still unresolved, honestly. As of this
weekend, ship 40 remains out there, still
afloat as far as anyone's confirmed, but the
recovery ship, Geo Australis has been
holding position near it rather than making
obvious progress. Prediction markets
watching this closely have it at somewhere
around an 18% chance of the ship actually
making it back to shore.
Avery: So not officially declared lost, but not
looking great either.
Anna: That's the honest summary, genuinely
unresolved. The one bit of good news is that
SpaceX already got what they really needed
from this before the weather turned close up
drone footage of the heat shield and engine
sections, which is the data that actually
matters for building the next ships. So Even
if ship 40 never makes it to port, the
programme's already moved
Avery: on to the next one, and life goes on
regardless. SpaceX isn't waiting around for a
resolution, not at all.
Anna: Ship 41's already working through its own
test sequence for Flight 14, which is
currently targeting around August 20th.
Booster 21's finishing up engine
installation for its own static fire testing,
and there's repair work underway at the pad
after flight 13. So whatever happens to
ship 40, the programme's already moved on to
the next one.
Avery: We'll keep an eye on it and let you know if
there's a final word either way.
Anna: Next up, and honestly, still probably the
single biggest storey of the week. Tuesday's
total solar eclipse.
Avery: We did a full deep dive Thursday, so quick
version for anyone catching up. A, uh,
182 mile wide shadow swept
from the Arctic Ocean down across eastern
Greenland and western Iceland and then out
across northern Spain before heading into the
Mediterranean.
Anna: The longest totality anywhere on land was 2
minutes 18 seconds at a dramatic
bird cliff on Iceland called La Tribarg.
Millions of people gathered across northern
Spain too. Towns like Valoria, Labuina
and Segur de Calafel were packed with
totality, arriving low on the horizon about
an hour before sunset for a genuinely
golden dramatic show.
Avery: And it wasn't just spectacle. Observers got a
rare direct look at the sun's corona, a
solar prominence and Jupiter, Jupiter,
Mercury and Venus all visible in the darkened
sky during totality.
Anna: One line from that episode that stuck with me
all week. An observer in Spain described it
as something that strikes the lizard part of
your brain that just tells you this shouldn't
be real.
Avery: Still the best description of totality we've
heard. And if you're already plotting your
next one, Spain gets another total solar
eclipse on August 2, 2027.
Anna: Less than a year away, eclipse chasers are
having a very good stretch.
Avery: Storey three. And, um, this one's fresh.
Yesterday's episode in fact. So if you're a
regular weekday listener. You've already
heard the full version, but for anyone
joining us just on weekends, here's the
headline.
Anna: Astronomers using the James Webb Space
Telescope found what they're calling a black
hole star bomb
BH1 out of the
Mirage or Miracle JWST
survey. It's a young, rapidly growing
black hole wrapped in such a dense,
turbulent cocoon of gas that the who whole
object glows almost like a star,
even though a black hole is doing the work at
the centre.
Avery: And it's ancient. The light left it about
660 million years after the Big Bang,
roughly 13 billion years ago, making it
the earliest confirmed object of its kind,
led by
Anna: Rohan Naidu at the University of Hawaii
and Yorat Matthy at the Institute of Science
and Technology Austria. And the reason it
matters beyond cool a weird object is
that it might explain a 50 year old puzzle
how supermassive black holes got so
big so early when normal gas
accretion shouldn't have had time to do it.
Avery: And, uh, it ties directly back to Thursday's
storey too, doesn't it? The three black holes
sharing one galaxy,
Anna: exactly the same puzzle from a different
angle. If black holes can hit these
accelerated growth phases, whether through a
gas cocoon like this one, or through merging
with each Thursday's trio, that gives them
a much faster route to becoming super
massive. Two chapters of the same bigger
storey,
Avery: basically back to back AJWST
just quietly having one of the best months of
any telescope ever built.
Anna: Last one Virgin Galactic. And this is a
storey that actually got worse as the week
went on.
Avery: We flagged the headline Thursday. Their
upgraded Delta class spacecraft, which was
supposed to start flying paying customers
this quarter, has slipped to February
2027. Company says they need more time
on avionics and systems installation before
putting people on board.
Anna: Shares dropped about 12% in after
hours trading when that news broke.
Avery: And then Wednesday the company reported its
second quarter results. And that's where it
got worse. Revenue came in at just
$1.54 million, well under
expectations, with a net loss of around
$55.9 million for the quarter.
Anna: The stock fell another roughly
7.7% on that news, and
management's now guiding toward some
genuinely rough cash burn for the rest of the
year, 95 to $100 million
going out the door in the third quarter
alone, 80 to 90 million in the fourth.
They've also filed paperwork that lets them
raise capital through stock debt or warrants
if they need to, which is the kind of filing
that exists specifically because a company
thinks it might need it.
Avery: That's not a great combination. Bigger
losses, a slipping timeline, and now, uh, the
option to dilute existing shareholders if
cash gets tight.
Anna: It's not, though there is one genuine bright
spot buried in there. Their
$750,000 a, uh, seat flight packages
were oversubscribed and the CEO said
they'll be offering higher price points when
ticket sales reopen this autumn. So whatever
else is going on, demand for an actual seat
isn't the problem,
Avery: which is sort of the whole Virgin Galactic
storey in one sentence. At this point, the
demand and the money are mostly there. It's
the hardware and the timeline that keep
slipping.
Anna: That's it exactly. We'll keep tracking it as
February 2027 gets closer.
Avery: Okay, that's the weekend wrap. A brand new
storey about empty space not actually being
empty. Plus updates on Starship Still Adrift
in the Indian Ocean, Tuesday's total solar
eclipse, yesterday's black hole star
Discovery, and Virgin Galactic's rough week.
Anna: A, uh, huge week for space and astronomy
news, and hopefully a useful ways to catch up
if you missed any of it along the way.
Avery: If you enjoyed today's episode, the best
thing you can do for us is leave a rating or
review wherever you're listening and share
the episode with a fellow space nerd. Full
show Notes, sources and links for every
storey we covered today are @astronomydaily
IO and you can find us on social media.
We're AstroDaily Pod pretty much
everywhere.
Anna: We'll be back Monday with our regular weekday
updates. Until then, keep looking up. Clear
skies, everyone.
Avery: See you next time.