Anna: Welcome to Astronomy Daily, your
trusted source for the latest space and
astronomy news. I'm Anna.
Avery: And I'm Avery. We've got some fascinating
Stories today from SpaceX Testing new
capabilities at the International Space
Station to some surprising revelations
about solar eclipse predictions.
Anna: Plus we'll dive into a long awaited
discovery involving Jupiter's moons and
get an update on SpaceX's ambitious
Starship programme in Florida. Let's jump
right in. Before we dive into today's
main stories, I have to say this has been
an incredible week for space news. It feels
like we're living through a real renaissance
in space exploration.
Avery: Absolutely, Anna. Between private companies
pushing the boundaries and NASA's missions
revealing new discoveries, it's hard to keep
up sometimes. Speaking of which, our
listeners have been asking for more technical
detail in our discussions, so we'll be diving
deeper into the science today.
Anna: Our first story takes us to the International
Space Station, where SpaceX just
completed a crucial test that could be game
changing for the station's future. On
September 3rd, a dragon cargo spacecraft
successfully performed what's called a
reboost of the ISS using two
of its Draco engines for just over five
minutes.
Avery: That's pretty impressive, Anna. So what
exactly does reboosting mean for those who
might not be familiar?
Anna: Great question. Basically, the ISS
is constantly losing altitude due to
atmospheric drag, even though it's about
250 miles up. Without regular
boosts, it would eventually fall back to
Earth. This particular test raised the
station from roughly 250 miles
to an orbit between
256 and 261
miles.
Avery: And I'm guessing this is especially important
because of the whole situation with Russia
potentially leaving the iss programme by
2028.
Anna: Exactly. Right now, Russian progress
vehicles handle most of the reboosting
duties. If Russia withdraws, NASA
needs alternative capabilities and this test
proves that SpaceX can step up. They
actually did their first reboost test back in
November 2024, and now they're planning
longer burns for fall 2025 to
really put the system through its paces. It's
worth understanding just how complex these
reboost manoeuvres are. The Dragon
spacecraft has to fire its thrusters in
precise coordination with the ISS's
attitude control systems. Too much
thrust and you could destabilise the
station's orientation. Too little and
the reboost is ineffective. The fact that
they achieved a 5 mile altitude increase with
just a 5 minute burn shows incredible
precision.
Avery: It's also worth noting that SpaceX will
eventually need these same capabilities when
it comes time. To safely deorbit the ISS
in a controlled fashion. So this
testing serves multiple purposes.
Anna: Now shifting our focus from low Earth orbit
to much deeper space, we have some
Fascinating news from NASA's James Webb
Telescope. Researchers have identified what
might be the most deep distant galaxy
ever observed, designated Jades
GS Z13.0,
which appears to have formed just
325 million years after the
Big Bang.
Avery: That's incredibly early in cosmic history.
Just to put that in perspective for our
listeners, if the Universe is about
13.8 billion years old,
this galaxy formed when the universe was less
than 3% of its current age.
How were astronomers able to determine such
precise ages for these ancient objects?
Anna: It all comes down to redshift, the phenomenon
where light from distant objects is stretched
to longer, redder wavelengths as the universe
expands, The Webb telescope can detect
these incredibly redshifted signatures in
infrared light. What's remarkable about this
particular galaxy is that it's not just
distant, but it's also surprisingly massive
and mature for its age, suggesting that
galaxy form happened much faster in the early
universe than we previously thought.
Avery: This discovery is really challenging our
models of early cosmic evolution. The
fact that we're finding these large, well
developed galaxies so early suggests that the
first stars in galaxies formed even faster
than our simulations predicted. It's
discoveries like these that make the James
Webb Space Telescope such a game changer for
astronomy.
Now, speaking of precision and accuracy, our
next story might surprise anyone who's ever
looked at those crisp, clean solar eclipse
maps. Turns out those neat lines showing the
path of totality. They're not nearly as
precise as they appear.
Anna: Oh, uh, this is fascinating stuff.
What's the issue exactly?
Avery: Well, it turns out the edges of totality are
actually fuzzy and can be off by hundreds of
metres. The problem stems from something
pretty. We're still debating the
sun's act size. The canonical
radius that's been used for over a century is
696,000 kilometres.
But new measurements suggest that might be
outdated.
Anna: So how much difference are we talking about
here?
Avery: Researchers Luca Qualia suggests the sun's
angular size is
959.95 arcseconds
versus the traditional
959.63.
That's a tiny difference, but it can shift
the eclipse path edge by up to
2,000ft. When you factor in the
sun's fuzzy photosphere and the moon's jagged
mountain peaks, things get even more
complicated.
Anna: So what are researchers doing about this?
Avery: They're creating new maps with zones of
uncertainty at the edges instead of those
precise lines. We're used to seeing. This is
especially important for the August 12,
2026 eclipse that will affect Spain and
Iceland. People planning trips definitely
want to know about these potential
variations.
Anna: This research is also revealing some
fascinating details about the lunar limb
profile, the jagged edge of the Moon created
by mountains and valleys. These
irregularities can create what astronomers
call the diamond ring effect and Baily's
beads during eclipses. Some areas along the
eclipse path might experience these phenomena
more prominently than others, depending on
which lunar mountains are silhouetted against
the sun.
Avery: Before we head out to Jupiter, let's take a
detour to Mars, where NASA's Perseverance
rover has made a potentially groundbreaking
discovery. The rover has detected what
scientists are calling convincing evidence of
ancient microbial life preserved in a rock
sample from Jezero Crater.
Anna: This is huge news. If confirmed, what
exactly did Perseverance find that's got
scientists so excited? I, uh, know they've
been looking for signs of ancient life in
Jezero craters since the rover landed.
Avery: The evidence comes from a rock nicknamed
Chayava Falls. Perseverance found
distinctive chemical signatures and
microscopic structures that are consistent
with ancient bacterial mats. The rock
contains organic compounds, mineral deposits
that typically form in the presence of water,
and what appear to be fossilised biofilms.
Of course, scientists are being very
cautious. They need the samples to return to
Earth for definitive analysis, which won't
happen until the Mars sample return mission
in the2030s.
Anna: What makes this discovery particularly
compelling is the location. Jezero
Crater was chosen precisely because it
contains the remains of an ancient river
delta, an environment that would have been
perfect for microbial life billions of years
ago. If these findings are confirmed, it
would be the first concrete evidence that
life once existed beyond Earth,
fundamentally changing our understanding of
biology in the universe.
Okay, our third story takes us to Jupiter,
where NASA's Juno mission has finally
solved a long standing mystery. After years
of searching, they've detected auroral
footprints from Callisto, the fourth and most
distant of Jupiter's Galilean moons.
Avery: Wait, so the other three moons, IO,
Europa and Ganymede, they already had
detected footprints?
Anna: That's right. These are basically auroral
signatures that show up in Jupiter's
atmosphere as each moon passes through the
planet's magnetosphere magnetic field. Think
of them like cosmic breadcrumbs. The other
three moons had been spotted before, but
Callisto's remained elusive despite
multiple attempts with the Hubble telescope.
Avery: So what changed? How did they finally spot
it?
Anna: The breakthrough came in September 2019,
when a massive solar stream hit Jupiter.
This shifted Jupiter's main auroral
oval. And in that shifted configuration,
Callisto's faint signature finally became
visible. It's much weaker than the others,
which explains why it took so long to detect.
But now we can confirm that all four
Galilean moons leave their mark on
Jupiter's magnificent auroral displays.
Avery: This discovery also tells us something
important about Callisto itself. Unlike, um,
the other Galilean moons, Callisto was
thought to have a relatively simple,
undifferentiated interior. But the fact that
it creates detectable auroral footprints
suggests it has some kind of conducting
layer, possibly a subsurface ocean like
Europa and Ganymede, which would make it
another potential target in the search for
life.
And finally, let's talk about what's
happening much closer to home here in
Florida. SpaceX is making rapid progress
on their starship infrastructure at Kennedy
Space Centre. And the scale of what they're
building is pretty remarkable.
Anna: This is at Both Launch Complex 39A
and Space Launch Complex 37. Right.
Avery: What exactly are they building at
39A? They've assembled a large crane and are
erecting a, uh, service structure with the
launch mount potentially in place by the end
of this year. But Space Launch Complex
37 could be even more impressive. It
might support dual launch towers and could
handle up to 76 annual launches.
Anna: That's an incredible launch cadence. When
are they targeting their first Florida
Starship flight?
Avery: SpaceX is aiming for late 2025 from
Launch Complex 39A, though many
observers think 2026 is more realistic.
Environmental reviews are currently
evaluating up to 44 annual Starship
launches from Florida, which would represent
a massive increase in the state's launch
capacity.
Anna: The scale of this infrastructure development
is really staggering. We're talking about
launch towers that will dwarf even the
vehicle assembly building at Kennedy Space
Centre. It's each Starship super heavy
booster stands nearly
230ft tall. And the
complete stack with starship reaches about
400ft taller than the Statue of
Liberty. The ground systems needed to support
this massive vehicle require
entirely new approaches to fueling,
servicing and launch operations.
Avery: From an economic perspective, this could
transform Florida's Space coast. With up to
76 annual launches from just one complex,
we could see launch frequency frequency that
rivals the entire global launch industry
today. That means thousands of jobs, not
just for SpaceX, but for the entire ecosystem
of suppliers, contractors and service
providers that support these operations. It's
reminiscent of the Apollo era, but
potentially even bigger.
Anna: It's amazing to think that 39A, which
launched Apollo missions to the moon and
space shuttle flights for decades, will soon
be home to the next generation of spacecraft
designed to take humans back to the Moon and
eventually to Mars.
Avery: Absolutely.
And that wraps up today's episode of
astronomy daily. From SpaceX testing new ISS
capabilities to discovering the limitations
of eclipse maps, from completing Jupiter's
Aurora Moon collection to building the launch
infrastructure of the future, it's been quite
a journey through the cosmos.
Anna: Looking at all these stories together,
there's a common thread. We're witnessing
unprecedented precision and capability
in space exploration. From SpaceX
Fine Tuning Orbital mechanics at the ISS
to JWST revealing the distant
past of our universe. From potentially
finding ancient life on Mars, to mapping
Jupiter's complex magnetosphere, each
discovery builds on the others.
Avery: What's particularly exciting is how these
developments are accelerating. Ten years ago,
many of, uh, today's stories would have
seemed like science fiction. Routine
commercial operations at the iss,
telescopes seen back to the cosmic dawn,
potential biosign signatures on Mars. The
next decade promises to be even more
remarkable, with lunar bases, Mars
sample returns, and interstellar missions
moving from concept to reality.
Anna: Thanks for joining us today. Don't forget to
subscribe and share Astronomy Daily with
fellow space enthusiasts. We'll be back
tomorrow with more exciting discoveries from
the universe around us.
Avery: Until then, um, keep looking up. I'm Avery.
Anna: And I'm Anna. Clear skies everyone.