Anna: Welcome to Astronomy Daily, your regular
dose of the latest and greatest from across
the cosmos.
Avery: We're your hosts, Avery and Anna, and we've
got some truly fascinating stories from the
world of space and astronomy for you today.
Anna: We'll be starting by remembering a true
legend of space exploration. Astronaut
James Lovell, whose incredible life and
contributions left an indelible mark on
humanity's journey to the stars. Then we'll
shift our gaze to the night sky, discussing
the upcoming Perseid meteor shower and
whether the bright moon might put a damper on
this year's viewing party. But don't worry,
we'll have some tips for you after
that. We're off to explore a groundbreaking
discovery by the Hubble Space Telescope,
which has revealed evidence of a rare white
dwarf collision, shedding new light on steel
stellar evolution.
Avery: And finally, we'll launch into a truly
ambitious concept, the potential for space
travel to a nearby black hole within the next
century, exploring the technology and the
scientific implications of such a monumental
journey.
Anna: So get ready for an exciting tour of
the universe.
We begin our show today with some somber news
from the world of space exploration. We're
reflecting on the remarkable life of
astronaut James Lovell, who sadly passed
away recently at the age of.
Lovell was a true icon, a member of
humanity's first trip to the moon and
famously the commander of NASA's challenging
Apollo 13 mission.
Avery: That's right, Ana. NASA announced his passing
and acting administrator Sean Duffy released
a statement saying, NASA sends its
condolences to the family of Captain Jim
Lovell, whose life and work inspired millions
of people across the decades. Jim's character
and steadfast courage helped our nation reach
the moon and turned a potential tragedy into
a success from which we learned an enormous
amount. We mourn his passing even as we
celebrate his achievements. It really speaks
volumes about the man he was.
Anna: Absolutely. He was a four time
Gemini and Apollo astronaut. But he's
perhaps most famously known for his portrayal
in the 1995 feature film
Apollo 13. Tom Hanks played him
and Lovell himself had a great sense of humor
about it, often joking at public appearances.
I know today when I came out, many of you
were expecting Tom Hanks, but you're going to
have to settle for little old me.
Avery: Such a humble man. His career was truly
groundbreaking. He was selected with NASA's
second group of astronauts in 1962
and first launched aboard Gemini 7 in
December 1965. This was a
pivotal mission as it was the first to
include a rendezvous with another crewed
spacecraft, Gemini 6. And he and
Commander Borman spent two weeks in Earth
orbit, setting the US record for the
longest spaceflight at the time, all in
preparation for the later Apollo missions.
Anna: And he was a key figure in demonstrating the
skills needed for lunar missions. He
commanded Gemini 12, the program's final
flight, where his crewmate Buzz Aldrin,
conducted the first truly successful
spacewalks, showing that astronauts could
effectively work outside a, uh, spacecraft.
This was a huge step forward for the program,
indeed.
Avery: Then came his first trip to the moon as part
of Apollo 8 in December 1968.
This mission was revolutionary, marking the
first time humans had flown to another
celestial body. Lovell, Bolt Borman and
William Bill Anders were the first to see the
far side of the moon with their own eyes and
captured the iconic Earthrise photographs,
which many credit with inspiring the
environmental movement. Lovell himself said,
you had to pinch yourself, hey, we're really
going to the moon. This is it. It
truly was a high point. As Lovell himself
later reflected, that mission brought a much
needed uplift to the American people during
the turbulent year when a telegram sent to
the crew stating, you saved
1968. But of course, the
mission that cemented his legend was Apollo
13 in April 1970. What was
intended to be NASA's third moon landing
quickly turned into a fight for survival
after an explosion tore through the
spacecraft's service module. That's when his
famous line, houston, we've had a problem
here came into play. He saw gas escaping
from the spacecraft and oxygen gauges
dropping to zero, and it was a dire
situation. But his calm leadership, along
with crewmates Fred Haise and Jack Swigert,
guided them through incredible challenges to
a safe splashdown. It was a testament to his
courage and ingenuity, turning a potential
tragedy into an incredible story of human
perseverance.
Anna: He was already a record breaker even before
Apollo 13, being the first person to launch
into space four times. After
his active flight career, Lovell continued to
contribute, serving as Deputy Director of
Science and Applications at what's now
Johnson Space center before retiring from
NASA and the Navy. He then moved into the
business world, holding executive roles and
serving on various boards.
Avery: And his contributions were recognized with
numerous accolades, including the
Congressional Space Medal of Honor and the
Presidential Medal of Freedom. He was
inducted into the International Space hall of
Fame, the US Astronaut hall of Fame, and the
National Aviation hall of Fame. A crater
on the far side of the moon was even named
for him in 1970.
Anna: His legacy extends beyond his professional
achievements. His family released, uh, a
statement saying they were enormously proud
of his amazing life and career
accomplishments highlighted by his legendary
leadership in pioneering human spaceflight.
But to all of us, he was dad,
granddad, and the leader of our family.
Most importantly, he was our hero. We
will miss his unshakeable optimism,
his sense of humor, and the way he made each
of us feel we could do the impossible. He
was truly one of a kind.
Avery: What a beautiful tribute. With James Lovell's
passing, only five of the 24 people who flew
to the moon during the Apollo program remain
Livin's. His contributions to space
exploration and his unwavering spirit will
undoubtedly continue to inspire generations
to come. He truly embodied the adventurous
and resilient spirit of human spaceflight.
Anna: From a somber reflection, we now turn our
gaze to a more regular yet still exciting
celestial event, the annual Perseid
meteor shower. August is often dubbed
meteor month for observers in the Northern
hemisphere, largely thanks to this
display.
Avery: That's right, Anna. It's beloved by everyone
from serious meteor enthusiasts to casual
summer campers. However, for 2025,
skywatchers need to be aware of a significant
obstaclethe Moon.
Anna: Unfortunately, this year the moon will turn
full on August 9th and will be in a very
bright, waning gibbous phase a few nights
later, right when the Perseid peak is
predicted to occur. And that's for the
overnight hours of Monday, August 11th
into the pre dawn hours of Tuesday, August
12th. Awaiting gibbous is just about the
worst moon phase for meteor observing.
Avery: It truly is. The moon will be 89%
illuminated and will be flooding the sky with
light through most of that keen night. This
will definitely hamper any serious attempts
to observe the meteors. It's a bit of a redux
of 1968 when the moon was in the same phase
during the Perseid peak. Back then, a meteor
watch in Central park only saw a about one
meteor every minute or eight, when
typically you'd expect one every minute or
two.
Anna: So quantity over quality then, because
moonlight only hides the fainter meteors.
Many Perseids are known to be fast, bright
and often leave persistent trains.
These brighter, streaky Perseids can
definitely burn right through a moonlit sky,
exactly as.
Avery: Uh, Guy Adewell notes in his Astronomical
Calendar 2025. Perseid meteors
are swift, many are bright. 1 White, yellow,
green, red, orange, leave spectacular
long lasting trains and end in flares. And
occasionally you get an outstandingly bright
Perseid fireball that blazes forth impressive
enough to attract attention even with bright
moonlight. So if you're willing to sacrifice
the sheer number of meteors, you might still
catch some truly spectacular ones.
Anna: The best time to watch, as always,
is from 11pm or midnight
straight on until the first light of dawn.
10 the meteors can appear anywhere in the
sky, so just make sure you're watching in a
direction where the Moon isn't directly in
your eyes.
Avery: It's definitely not the ideal year, as a
single observer in the absence of moonlight
might see 45 to 90 meteors per hour.
We won't come close to that in 2025,
but for those already thinking ahead,
2026 promises a much better show,
with the peak night coinciding with a new
Moon and even a solar eclipse. The so while
this year is challenging, next year will be a
different story. In the meantime, keep an eye
out for a few celestial streakers and don't
forget the eye catching conjunction of
Jupiter and Venus. Low in the east northeast
sky a few hours before sunrise. It's a nice
constellation prize for the Moonlit Perseids
of 2025.
Anna: From looking at our own skies, let's now
pivot to a truly fascinating discovery
made possible by the venerable Hubble Space
Telescope. It has uncovered compelling
evidence of a rare white dwarf merger,
shedding new light on stellar evolution and
the ultimate fates of binary stars.
Avery: This is a significant finding. Scientists at
the University of Warwick detected carbon in
the ultra massive white dwarf known as
WD0525526,
which is located about 130 light years away.
In optical light, it looks like an ordinary
hydrogen rich white dwarf, but Hubble's
ultraviolet spectra revealed something much
more unique.
Anna: That faint carbon trace in its atmosphere is
the telltale sign that this object is the
product of a rare white dwarf merger rather
than just a single star's evolution. What's
even more remarkable is that the detected
carbon is four to five orders of
magnitude lower than in previously known
merger remnants, making this the earliest
stage example of such a merger found so far.
Avery: It really highlights the power of ultraviolet
observation. Normally, ultramassive white
dwarfs hide their carbon beneath thick
hydrogen and helium envelopes, but in
WD0525526
these layers are 10 billion times
thinner. This thinning likely resulted from
two stars merging and burning off their outer
layers during the cosmic collision. The
leaving behind a stripped remnant with a
nearly pure hydrogen atmosphere, yet
with carbon still leaking through.
Anna: And the mechanism behind this carbon leakage
is also quite intriguing. At nearly four
times the sun's surface temperature,
WD0525526
is too hot for typical convection to bring up
carbon. Instead, the team identified
semiconvection, a subtle mixing Process
never before seen in white dwarfs that allows
a modest amount of carbon to drift upward.
This opens a new chapter in stellar physics.
Avery: The discovery challenges previous assumptions
that hydrogen rich white dwarfs lack carbon.
It implies that low level carbon pollution
might be hidden beneath thin atmospheres in
many ultramassive white dwarfs, only
detectable with sensitive ultraviolet data.
Anna: This research deepens our understanding of
cooling delays in what's called the Q branch
of the Gaia hertzsprung Russell diagram,
which is linked to core crystallization.
It also ref binary merger rates and
helps us better identify potential
progenitors of Thermonuclear Supernova
WD0525526
acts as a benchmark for models of stellar
mergers and white dwarf evolution.
Avery: It's incredible that Hubble, even at 35 years
old, is still the only telescope capable of
making such observations. The researchers
stress the vital importance of planning for a
new ultraviolet observatory to continue this
work and survey more ultramassive white
dwarfs across the galaxy, which could reveal
a whole hidden population of these rare
merger remnants.
Anna: From uncovering hidden stellar secrets with
Hubble, let's now set our sights on an even
more ambitious concept. The idea of
interstellar travel to a black hole.
It sounds like something out of science
fiction, but a new concept by astrophysicist
Cosimo Bambi of Fudan University
suggests a tiny laser propelled probe
could actually make this trip to within a
human lifetime.
Avery: That's absolutely mind blowing. This
vision, published in Eye Science, outlines
how gram scale nanocrafts could journey to
a nearby black hole and directly test the
depths of gravitational physics. The first
challenge, of course, is finding a hidden
black hole. Close enough.
Anna: Exactly. Known black holes like Jaia
Baeshuan, uh, are over 1500 light years
away. But Bambi estimates there might be 1
within 20 to 25 light years. Based on
stellar and white dwarf densities in galactic
region. Detecting one would require new
techniques such as microlensing or
gravitational wave events, which could pick
up the pull of an otherwise invisible object.
Given rapid advances in these methods, Bambi
argues we could locate a suitable target
within 10 years.
Avery: That's a much shorter timeline for finding
one than I would have thought. The core of
this incredible mission lies in those
nanocrafts. They'd be space probes or
weighing just a few grams, Essentially a
silicon chip like wafer with a reflective
light sail made from advanced metamaterials.
A powerful laser array on Earth would
push the sail, accelerating the craft to
speeds approaching a third of the speed of
light.
Anna: And at that astonishing speed, a black hole
20 to 25 light years away could be reached in
about 60 to 75 years. Once the data
is gathered, the signals would take another
20 to 25 years to return, making the
mission's full timeline around 8, 80 to 100
years, potentially even shorter if higher
speeds are achieved.
Avery: This isn't just about the journey. It's about
the extraordinary experiments they could
conduct Near a black hole's extreme gravity.
For instance, if two or more nanocrafts were
used, One could orbit closer while another
observes. The inner craft would beam, uh, a
steady electromagnetic signal Back to its
partner According to general relativity. The
timing of that signal should match
predictions of the Kerr metric, which
describes spacetime Around a rotating black
hole. Any deviations could reveal new
gravitational physics.
Anna: Another fascinating test involves approaching
or even crossing an event horizon. If a
nanocraft falls into a true black hole,
Its signal should become increasingly
redshifted until it vanishes from view. But
if the object is a fuzzball with no horizon,
the signal might disappear suddenly. Only a
direct mission could truly reveal the truth.
They could even test if fundamental
constants, like the fine structure constant
change under intense gravity.
Avery: Despite the incredible scientific payoff,
There are major hurdles. The laser
infrastructure alone would cost an estimated
1 trillion euros today. Though Bambi
expects costs to drop significantly over the
next two to three decades, Nanocraft
technology, including durable light sails and
miniaturized instruments, still needs
development and communication across light
years. Navigation and target precision are
daunting.
Anna: Yet as Bambi points out, Breakthroughs once
deemed impossible, like detecting
gravitational waves or imaging black hole
shadows, are now realities. His
goal is to spark a conversation that could
launch a century long project,
Potentially opening a direct window into
gravity's most extreme realm.
Avery: It's truly inspiring to think that future
generations Might begin building and planning
for such a mission. While today's scientists
are laying the groundwork. This interstellar
ambition could transform astrophysics,
Allowing direct measurements of spacetime and
extreme gravity that either reaffirm or
challenge Einstein's theory.
Anna: Well, that brings us to the end of another
fascinating episode of Astronomy Daily. Thank
you so much for joining us today.
Avery: It's been quite a journey through the cosmos,
hasn't it? We remembered the incredible
legacy of astronaut James Lovell. We
discussed the challenging Perseid meteor
shower this year, and explored Hubble's
amazing discovery Of a rare white dwarf
collision.
Anna: And of course, we dared to dream about the
possibility of sending nanocrafts to a black
hole within the next century. There's always
so much happening in the universe.
Avery: Indeed, there is. We hope you enjoy
diving into these stories with us, and please
visit our website at, uh, astronomydaily
IO for more news and to listen to our back
episodes.
Anna: Join us next time for more celestial insights
and the latest news from beyond our world.
Until then, keep looking up