Anna: It aborted at zero. It got scrubbed
by the weather, and then on the third try,
it flew and came down in the Indian
Ocean softer than it ever has before.
Avery: Starship's 13th test finally left the
pad. That's our lead then, the strongest
sign yet of a moon beyond our solar system.
A robot mechanic heading for the graveyard
belt of dead satellites. And what the
far side of our own moon has been quietly
recording about the Earth.
Anna: It's the weekend wrap. I'm Anna.
Avery: And I'm Avery. This is Astronomy Daily.
Anna: So we have been living with this one for
weeks and I want to give it the room it
deserves because the story of Flight 13
is really the story of persistence.
Let's rewind. For anyone just joining US Back
on 16 July, SpaceX counted all
the way down to zero, and the rocket's own
flight computer said no. 4 of the
33 Raptor engines on the booster didn't
come up to healthy starting conditions and
the vehicle aborted, uh, itself on the pad.
That's not a failure, by the way. That's the
safety system doing exactly what it's built
to do.
Avery: Right? An abort at uh T0 is the
rocket protecting itself and the pad. Elon
Musk said afterwards two Raptors would be
pulled and replaced to be confident of a good
flight. They swapped the engines, rolled back
out. And then last week, the weather turned.
Thursday's attempt got scrubbed because
SpaceX wanted clear skies, not just for the
launch, but to actually see the vehicle and
photograph the heat shield under high stress
on the way up.
Anna: And that brings us to Friday, the 24th
liftoff from Starbase in Texas, just
before quarter to seven in the evening
Eastern time. So prime time viewing across
North America and the small hours of Saturday
morning for us here in Australia. This was
the second flight of the bigger, more
powerful version 3 Starship. And this
time it went, let's walk
Avery: the flights because there's real nuance here.
Not everything was perfect. And, um, that's
okay. First, the good news that matters most
for the program. The heat shield basics
and Musk both flagged a, uh, marked
improvement in how the shield held up during
re entry. And that is the single hardest
problem standing between Starship and genuine
reusability. If you can't bring the ship home
intact, none of the rest works.
Anna: The booster, super heavy, separated
cleanly a few minutes in and flew itself back
for a controlled splashdown in the Gulf of
Mexico about six minutes after launch.
But here's the honest on that
final landing burn, it looked like only about
five of the 13 planned engines lit,
so it came down harder and faster than
SpaceX wanted.
Avery: Now, important context, so nobody mishears
this. That booster was always going to be
thrown away in the water. This wasn't the
catch attempt. So a rough splashdown on an
expendable booster is a data point, not a
disaster. And crucially, it still made a
controlled landing, which means they appear
to have fixed whatever caused them to lose
the booster outright. On Flight 12 back in
May, that one lost engines after separation
and just fell into the Gulf. This one
flew the profile. That's progress.
Anna: Then the star of the show, the ship itself.
Ship 40 sailed through its burn,
coasted on a suborbital arc. This was never
going all the way to orbit and did something
lovely on the way. It relit one of its
Raptor engines in space. That in space
relight is a rehearsal for the maneuvers a
future orbital starship will need to come
home. And then came the splashdown west
of Australia in the Indian Ocean.
Avery: And this is the bit I keep replaying.
SpaceX's Dan Huat called it live,
the softest splashdown they have ever had
with Starship for the first time. After the
ship did its flip and settled onto the water
and tipped over, it did not explode.
It sat there bobbing, still sending back
telemetry and video floating in the Indian
Anna: Ocean, which, if you've watched these tests,
is genuinely new. We are used to the
fireball as the full stop at the end of the
sentence. This time the sentence just
kept going.
Avery: There's one more first, and it's a big one
for the Starlink side of the business. On the
way up, the ship deployed 20 real Starlink
V3 satellites, the first V3s ever to
fly. Every previous flight that tested
deployment used dummy mass simulators. These
were the real thing, big flat satellites with
laser links and large solar arrays. And
SpaceX says they successfully talked to all
of them by radio and laser and pulled
telemetry down, which six of
Anna: those 20 carried cameras specifically to
scan Starship's own heat shield tiles and
beam the pictures back. A clever way to
inspect the shield in flight. The satellites
then follow the ship's path back down. So
they're not staying up there. It's a test
appointment, not a Constellation launch.
Avery: So how do we score Flight 13 overall?
SpaceX and Musk both called it a success.
And I think the fair read is a strong
flight with one soft spot. The heat
shield improved. The ship flew its whole
profile and relit in space. The softest
ever splashdown first real V3
deployment set against a booster landing
burn, uh, that underperformed on an
expendable stage.
Anna: And a lovely piece of timing to close on the
original Launch date. The 16th was the
57th anniversary of the Apollo 11
launch. Friday's launch date. The 24th
of July is the 57th anniversary
of the day the Apollo 11 crew splashed back
down on Earth in 1969. A
splashdown anniversary for a rocket that's
meant to help carry the next crew to the
moon.
Avery: The road ahead is still steep. SpaceX has to
dramatically raise the flight rate, prove
they can catch the ship on the tower like
they catch boosters and crack an orbit
refueling before starship can land Artemis
astronauts. But after weeks of near misses,
Flight 13 is exactly the kind of day the
program needed.
Anna: Alright, let's move on to other news from the
past in space.
Avery: From our own backyard to 70 odd light
years away and a discovery with a southern
hemisphere fingerprint all over it.
Astronomers using the European Southern
Observatory's Very Large Telescope up in
the Chilean desert have reported the
strongest evidence yet for a moon outside
our solar system. It's in a system called
CD35 20072 2.
And it is, in the lead author's own words,
super weird.
Anna: Weird how? Well, we've found more than
6,000 planets around other stars, but
never once confirmed a moon out there. Every
candidate so far has been contested. So what
makes this one different?
Avery: This is the twist. It didn't turn up the way
exomoon hunters expected. A little moon
crossing in front of a planet. Instead, the
team led by Kevin Hoy, an um ESO
student based in Chile with Alice Zurlo and
colleagues, published in Nature, watched a
brown dwarf and caught it wobbling. Something
is tugging on it. And that something is a gas
giant about the mass of Jupiter orbiting the
brown dwarf.
Anna: So let me get the nesting doll right, because
it's genuinely strange. There's a star
about half the mass of our own sun. Around it
orbits a brown dwarf bigger than a planet,
too small to be a star, around 30 times
the mass of Jupiter. And around the brown
dwarf orbits this Jupiter mass object.
Avery: Exactly. And that's why nobody quite knows
what to call it. It's the size of a planet,
but it doesn't orbit a star. It orbits an
object that orbits a star. So is it a moon?
An exosatellite? The researchers
themselves say there's no officially accepted
definition of an exomoon. And this system
blurs every line between star, planet
and moon.
Anna: And the honest headline, because this
matters, is that the team calls it the first
plausible detection of an exosatellite.
Not confirmed plausible, the strongest
candidate we've had, but still one that needs
more observations to nail down.
Avery: The technique is the exciting part. For what
comes next. They used radial velocity,
the same wobble method that found the first
exoplanet around a sun like star back in the
90s, but applied it to a directly
imaged brown dwarf for the first time. Which
means, uh, every one of those directly imaged
giant worlds out there is now a fresh hunting
ground for moons.
Anna: A new door opened from a telescope under the
southern skies. We'll be watching CD
352722 closely.
Avery: Next up in our weekly roundup, Northrop
Grumman MRV MEP.
Anna: Here's a job title you don't hear every
satellite mechanic. On Tuesday evening, a
SpaceX Falcon 9 lifted off from Cape
Canaveral carrying one of the more quietly
futuristic missions of the year. Northrop
Grumman's Mission Robotic Vehicle, plus
three of what the company literally calls
jetpacks.
Avery: I love this because it's so practical. We
put enormous expensive satellites up in
geostationary orbit. The ring about
36,000 km up, where a
spacecraft hovers over the same spot on
Earth. And historically, when one runs out of
maneuvering fuel, that's the end of it. A
perfectly good satellite, dead because the
tank's empty.
Anna: So what does the mechanic do about it?
Avery: The Mission robotic vehicle, the MRV,
carries two fully articulated robotic
arms, each about 3 meters long, built by
the U.S. naval Research Laboratory under a
DARPA program. Over the next year, it climbs
out to geostationary orbit. And then it
starts making house calls. It grabs one of
those mission extension pods, the jetpacks,
and bolts it onto an aging satellite. The
pod becomes a satellite's new propulsion,
buying it something like six extra years of
life.
Anna: And then it moves on to the next customer.
One robot, three pods, three rescued
satellites. Here's the local hook. Among the
named clients are SES in Luxembourg,
and this one's for our Australian listeners,
Optis. So there's a genuine chance an
Aussie communications satellite gets a new
lease on life from this robot.
Avery: This isn't coming out of nowhere either.
Northrop Space Logistics Arm did this before
with its mission extension vehicles. The
first one, back in 2019, was the first
commercial spacecraft ever to dock with a
live satellite in geostationary orbit. But
those were big. One to one. One
vehicle, one satellite for good.
Anna: Whereas the pods are smaller, cheaper and
reusable in the sense that the robot can keep
deploying them. It turns satellite servicing
from a one off rescue into something closer
to a routine a tow truck service for the
geostationary belt.
Avery: And, um, in an era we're all worried about
space junk keeping working satellites working
instead of abandoning them and launching
replacements is a genuinely good news story
about doing more with less up there.
Anna: Next. Chang' E6 Far Side Solar wind.
Avery: Our last highlight brings us home to our own
moon and a result that turns lunar soil
into a diary of the Earth. This is from
China's Chang' E6 mission, the one that
pulled off the first ever sample return from
the far side of the Moon. The findings are
published in Nature Geoscience.
Anna: And it starts with a question I'd never
thought to. Does the solar wind hit the
near side and the far side of the Moon the
same way?
Avery: Turns out, no. The solar wind is this
constant stream of charged particles pouring
off the Sun. The Moon has no real atmosphere
and no global magnetic field. So those
particles slam straight into the dust. And
over billions of years, that dust, the
regolith, becomes an archive, trapping
noble gases, helium, neon, argon,
krypton, xenon.
Anna: So the team compared the far side dirt that
Chang' E6 brought back from the South Pole
Aitken Basin with the near side samples from
the earlier Chang' e 5 mission. And the two
sides tell different stories.
Avery: They do. The far side samples show the
solar wind penetrating deeper and a
distinctly different neon fingerprint. And
the culprit they land on is us,
uh, the Earth. For part of every month,
the Moon's near side sits inside the Earth's
magnetosphere, our planet's magnetic shield.
And that shield actually slows the solar wind
down before it reaches the near side.
Anna: The far side, meanwhile, spends more of its
time fully exposed, taking the solar wind at
full speed. Though the Earth has, in effect,
been leaving its signature on one face of the
Moon and not the other for billions of years.
Avery: And that's the poetic bit. The far side of
the Moon, the side we never see from here,
has been keeping a record of the Earth's own
magnetic environment across deep time.
To be fair, the scientists say the neon
result is still a bit of a puzzle. More than
one process is probably at play. But the
headline stands. The Moon's two faces have
lived through different weather from the sun.
And the Earth is part of the reason.
Anna: A little over a gram and a half of farside
dust, rewriting how we think about the Sun,
Earth, Moon system. Not bad.
Avery: Finally today, our regular sky watch for
both hemispheres.
Anna: Well, that was the week that was. Which means
it's time to look up wherever you are. Lets
start with the moon itself because it's the
main character in the sky. Right now we're
heading toward a full moon, the buck moon on
the 29th. So tonight and over the weekend
you've got a big bright waxing gibbous moon
lighting up the evening sky, north and
Avery: south alike, which is beautiful to look at
and a nuisance if you're chasing meteors. So
let's set expectations. Honestly, the
southern Delta Aquariids are active right now
and they peak on the 29th into the 30th
southern hemisphere. Friends, this shower is
ours. The radiant near the star Skat in
Aquarius rides high overhead for us and
it's also a fine show from the southern
United States and the tropics.
Anna: But here's the catch. This year that peak
lands right on the full buck moon, so the sky
will be washed out at exactly the wrong
moment. My advice, don't pin your hopes on
peak night. Go out in the dark window before
dawn once the moon has set and look well away
from it. The Delta Aquariids are faint, so a
truly dark patch of sky is everything and
a nice the slow bright fireballs of the
Alpha Capricornids are peaking around the
same nights for both hemispheres.
Avery: And if the moon spoils this one, don't
despair because the big one is coming and the
timing is perfect. The Perseids are
already switching on and they peak on the
12th into the 13th of August on a new moon.
Dark skies, no interference. That's a
Northern Hemisphere favorite. The radiant
sits high in the north, but it carries down
to the Southern hemisphere's mid latitudes
too. So it's worth a look. From Northern
Australia bark that date because
Anna: it's a genuine double feature. On the very
same day as the Perseid peak, 12 August,
there's a total solar eclipse.
Avery: There is. Totality carves a narrow path
across Greenland, Iceland and Spain if
you're lucky enough to be under it. That's
the whole day sorted. Eclipse in the
afternoon, meteors overnight. For most of
North America and Western Europe, it's a
partial eclipse rather than total, but still
very much worth stepping out for.
Anna: And this is our uh, non negotiable reminder.
Never look at even a partial eclipse without
proper certified eye protection. Solar
viewers that meet the ISO
123122 standard
ordinary sunglasses will not protect your
eyes. No exceptions.
Avery: Please take care of your eyes safety first
and all of that. As for planets, step out
after sunset and brilliant Venus is climbing
back into the western evening twilight it
only gets better through August and if you're
an early riser the pre dawn sky is where
the action is Saturn is well up in the hours
before sunrise with Jupiter returning low in
the east southern hemisphere viewers get
these morning planets riding higher and
steeper one of the quiet perks of our
southern skies so a
Anna: bright moon this weekend patience on the
meteors and a spectacular double bill to
circle for the 12th of August that's
Avery: the weekend wrap Starship's 13th
finally flew and floated the strongest
hint yet of a moon around the distant brown
dwarf a robot mechanic on its way to the
satellite graveyard and the far side of our
moon cor quietly keeping the
Anna: earth's diary thanks for spending part of
your weekend with us you'll find every source
in the show notes and we're back tomorrow
with your daily space and astronomy news
until then from Anna and
Avery: uh Ivory clear skies.
The
toll.