Astronauts Homeward Bound, Sun's Secrets Unveiled, and Uranus's Heat Revelation

Anna: Welcome to Astronomy Daily, your daily dose

of cosmic updates and celestial wonders. I'm

your host, Anna, and I'm thrilled to dive

into some truly captivating space news with

you today. First, we'll be looking at the

return trip of private astronauts from the

International Space Station after an extended

stay highlighting their incredible work and a

new splashdown location. Then we'll zoom in

on our very own star, the sun, as NASA's

Parker Solar Probe sends back the closest

ever images, revealing groundbreaking

insights into solar weather. Our journey

continues with a global launch roundup

featuring a busy week for space agencies

worldwide, including cargo resupply missions,

maiden rocket flights and a flurry of

Internet satellite deployments. And finally,

we'll uncover a surprising new discovery

about the distant ice giant Uranus that might

just rewrite its planetary history and

bolster the case for a future mission. So

buckle up because there's a lot to explore.

We kick things off today with news from above

our heads as the four intrepid astronauts of

Axiom Space's latest private mission,

AX4, have successfully concluded their stay

aboard the International Space Station and

are, uh, currently headed home. Their SpaceX

Crew Dragon capsule, aptly named Grace,

undocked from the ISS this morning, July 14,

marking the final leg of their journey back

to Earth. The undocking happened

precisely at 7:15am EDT.

Grace then gracefully maneuvered away from

the orbital laboratory which had been the AX4

crew's home for the past two and a half

weeks. This was actually a bit longer than

their originally planned two week stay,

giving them even more time to complete their

extensive research. Leading the AX4

mission was Commander Peggy Whitson, a former

NASA astronaut and now Axiom's Director of

Human Spaceflight. As Grace cleared the

isss safety keep out sphere,

Whitson transmitted a heartfelt message

saying Space Station grace, the AX4 crew

wants to thank you very much for your

support. You guys are amazing.

This mission marks Whitson's fifth trip to

orbit, pushing her impressive record for most

cumulative days in space by an American to an

incredible 695 days.

Her crewmates included pilot Shubanshu Shuks

Shukla and mission specialists

Slawas Suave, Uznansky

Wisniewski and Tibor Kapu. What's

particularly exciting is that this was the

first space flight for Shucks, Suave and

Kapu. And they also made history as the first

citizens of India, Poland and Hungary

respectively to launch on a mission to the

International Space Station. Throughout their

time in microgravity, the AX4 crew

undertook more than 60 experiments and

technology demonstrations with contributions

from a remarkable 31 different nations.

They also participated in numerous public

outreach events, setting a new record for

Axiom as the company continues to refine its

orbital operations. Launched aboard

a SpaceX Falcon 9 rocket from NASA's storied

Launch Complex 39A in Florida on

June 26, the crew spent just over a day

catching up to the International Space

Station after their extended mission. The

departure procedures began early this morning

with the crew entering Grace and closing the

hatch. Now Grace and its crew are on a

22.5 hour trajectory, set to splash

down in the Pacific Ocean off the coast of

California early on Tuesday, Eastern Daylight

Time. This will be a notable event as it's

only SpaceX's second West coast crew

recovery. Following the Crew 9 ISS

mission in March, SpaceX has made a permanent

shift to Pacific Ocean recoveries instead of

the Atlantic or Gulf, a uh change driven by

instances of debris from Dragon's trunk

surviving atmospheric reentry and crashing

back to Earth. This new re entry path

significantly minimizes the chances of such

debris causing any damage or injury,

prioritizing safety for everyone.

Now let's turn our gaze to our closest star,

the sun, where NASA's Parker Solar Probe

continues to redefine our understanding.

Understanding this incredible spacecraft

is certainly no stranger to breaking records.

On December 24, 2024, Parker

made history by flying closer to the sun than

any spacecraft ever, reaching a mere

3.8 million miles from the solar surface.

In doing so, it entered the outermost layer

of the Sun's atmosphere, the corona. During

this daring flyby, it also broke its own

record as the fastest human made object,

soaring at an astonishing 430,000 miles per

hour. Recently, NASA released some

truly remarkable video footage captured

during this historic flyby, offering us the

closest views of the sun ever recorded.

These groundbreaking images were captured by

Parker's Wide Field Imager for Solar Probe or

Wispiar, revealing a uh, never before seen

perspective of the Sun's corona and the solar

winds shortly after they're released from it.

As Nikki Fox, Associate Administrator for the

Science Mission Directorate at NASA

Headquarters, noted, Parker Solar Probe has

once again transported us into the dynamic

atmosphere of our closest star. She

emphasized the incredible advantage of

witnessing where space weather threats to

Earth begin with our eyes, not just

with models. This new data

is set to vastly improve our space

weather predictions, enhancing the safety of

our astronauts and the protection of our

vital technology both on Earth and throughout

the solar system. WISPR's images have

unveiled an important boundary within the

Sun's atmosphere known as the heliospheric

current sheet, where the Sun's magnetic field

Dramatically shifts direction from north to

south. Even more impressively, it captured

for the first time in high resolution

collisions between multiple coronal mass

ejections, or CMEs. These

CMEs are major drivers of space weather and

are crucial for understanding risks to

astronauts and Earth based technology like

power grids and communication satellites.

Angelus Vorlidas, the Whisper instrument

scientist, explained that in these images,

we're seeing the CMEs basically piling up on

top of one another. We're using this to

figure out how the CMEs merge together.

Before the Parker Solar Probe, NASA and its

international partners could only study solar

wind from a distance. That's why Parker has

been instrumental in bridging key knowledge

gaps. It identified the widespread presence

of switchbacks, which are zigzagging magnetic

field patterns Even at distances of around

14.7 million miles from the sun,

linking them directly to the origins of one

of the two main types of solar wind. Closer

in, at just 8 million miles, Parker revealed

that the boundary of the Sun's corona Is far

more uneven and complex Than previously

imagined. But the probe's discoveries

didn't stop there. The big unknown has always

been how solar wind is generated and how it

manages to escape the Sun's immense

gravitational pull. Noor

Rawafi, the project scientist for Parker

Solar Probe, Described understanding this

continuous flow of particles, especially the

slow solar wind, as a major challenge,

Particularly given the diversity in the

properties of these streams. However, thanks

to Parker Solar Probe, scientists are closer

than ever to uncovering their origins and how

they evolve. Prior to Parker Solar Probe,

distant observations suggested there were two

varieties of slow solar wind differentiated

by the orientation or variability of their

magnetic fields. One type, called

alphenic, Exhibits small scale switchbacks,

While the second, non alphenic, does not.

As it spiraled closer to the Sun, Parker

confirmed the existence of both types. Its

close up views are also helping scientists

distinguish the origins of these two unique

types. It's believed that the non alvenic

wind May emerge From features called helmet

streamers, Large loops connecting active

regions where some particles can heat up

enough to escape. While the alphenic wind

might originate near coronal holes, which are

dark, cooler regions in the corona. As Adam

Sabo, Parker Solar Probe mission scientist,

put it in we don't have a final consensus

yet, but we have a whole lot of new

intriguing data. So how does the

Parker Solar Probe Manage to endure such

extreme conditions? From the freezing cold of

deep space to the intense heat near the Sun?

A, uh, key factor in its survival lies in the

fundamental difference between temperature

and heat. While the space near the sun can

reach temperatures of several million

degrees, this doesn't necessarily mean

there's a lot of heat transferred. This is

because the Sun's corona is incredibly thin,

meaning there are far fewer particles. Even

though individual particles in the corona are

exceptionally hot, their scarcity means the

probe doesn't receive much actual heat.

NASA scientists explain that while the probe

travels through space with temperatures of

several million degrees, the surface of its

heat shield facing the sun will only be

heated to about 2500°F,

or roughly 1400°C.

These temperatures are, of course, still

incredibly hot, which makes its robust heat

shield, the Thermal Protection System, or

tps, absolutely essential. This

shield is crafted from a carbon composite

foam sandwiched between two carbon plates.

Carbon is an ideal material for this purpose

because it is both remarkably lightweight and

capable of withstanding extremely high

temperatures without melting. Tested to

withstand up to 3,000 degrees Fahrenheit, or

1,650 degrees Celsius, the

TPS can handle any heat the sun sends its

way, keeping almost all the probe's

instrumentation safe. Its unique structure

enables it to endure intense heat while

minimizing weight, a crucial factor for a

spacecraft designed to travel at such extreme

speeds. Furthermore, the outer surface of

the TPS is coated with a white ceramic paint

designed to reflect as much solar energy as

possible and further reduce the amount of

heat absorbed.

Next, let's look at this week's launch

schedule. And this week has certainly been a

whirlwind in the world of space launches,

with multiple missions lifting off from sites

across the globe. First, from China,

their latest cargo supply mission to the

Tiangong Space Station successfully lifted

off The Chang Geng 7 rocket. Launched the

Tianzhou 9 cargo vehicle from the Wencheng

space launch site on Monday, July 14.

This mission brings essential supplies for

the Shenzhou 20 crew, including food,

life support, scientific experiments, and

propellants. Notably, it also delivered

two upgraded Fei Shen extravehicular activity

suits designed for extensive use.

Tianzhou 9 is expected to spend six to seven

months at the station carrying a substantial

7,400kg of cargo,

showcasing China's robust orbital resupply

capabilities. Meanwhile, a significant

milestone is on the horizon for Australia.

Gilmour Space is gearing up to try again for

its second attempt at the maiden launch of

its Eris small satellite rocket this

Wednesday, July 16, from the Bowen Orbital

Spaceport. This pivotal launch follows a

previous stand down in May due to an

unexpected power surge. Now mitigated,

this three stage Eris launcher, proudly

Australian made, is poised to become the very

first orbital launch from from Australian

soil performed by a sovereign built vehicle.

Standing at 25 meters tall, Eris can carry

payloads of up to 215 kilograms to a

500 kilometer Sun Synchronous Orbit.

Its first stage uses unique hybrid Sirius

engines and a successful orbital launch would

also mark a historic first for a hybrid

rocket design globally. Gilmour

Space recently partnered with Tokyo based

Space bd, opening up opportunities for

Japanese and global satellite customers.

And Speaking of busy, SpaceX continues its

relentless pace with a packed schedule of

launches, predominantly expanding Internet

satellite constellations earlier this week,

a Falcon 9 rocket launched 26 Starlink

VTU mini Internet satellites into low Earth

orbit from Vandenberg, California. This

particular launch was significant as it

marked the 150th consecutive successful

mission for a Falcon rocket since an anomaly

back in July 2024. A truly remarkable

streak. Looking ahead, SpaceX is also

set to launch its very first contracted batch

of Amazon's Kuiper satellites this Wednesday,

July 16th from Cape Canaveral in Florida.

Project Kuiper is Amazon's direct competitor

to Starlink, aiming to build its own massive

Internet constellation. This mission will

carry at least 20 of these crucial

satellites. Amazon faces ambitious

deadlines, needing to launch its full

constellation of over 3200

satellites by July 2029,

with half required by July 2026.

This requires numerous launches across

various providers. To round out

SpaceX's week. Two more Starlink launches are

scheduled from Vandenberg. On Wednesday, July

16, another Falcon 9 will launch satellites

into Starlink's Group 17 shell, flying into

a highly inclined sun synchronous orbit.

And finally, on Sunday, July 20, a third

batch of Starlink satellites will launch from

the same California pad, completing a

remarkably busy period for SpaceX and further

expanding global Internet access.

Now let's turn our attention to one of our

solar system's distant ice giants, Uranus,

which is proving to be far more fascinating

than we once thought. New

scientific findings have revealed something

quite surprising about this enigmatic planet.

It's emitting its own internal heat, even

more than it receives from the sun. This

discovery actually contradicts observations

made by NASA's Voyager 2 probe nearly four

decades ago. Back in 1986,

Voyager 2 flew by Uranus, and its readings

suggested the planet didn't have significant

internal heat. However, new research

led by Xinyue Yang of the University of

Houston analyzed decades of spacecraft

readings and computer models. Their findings

indicate that Uranus emits 12.5%

more internal heat than it absorbs from solar

radiation. While this is less than other

outer planets like Jupiter, Saturn, and

Neptune, which radiate 100% more heat than

they receive, it's still a significant amount

that challenges our previous understanding.

It turns out we might have caught Uranus at a

peculiar time during the Voyager 2 flyby,

with some readings potentially skewed by a

surge in solar weather. By combining archival

data with advanced computer models,

scientists now believe this internal heat

suggests a completely different internal

structure or evolutionary history for the

planet. For a long time, it was thought that

Uranus formed closer to the sun before

migrating outwards. These new

findings are now calling that story into

question. This fresh understanding of

Uranus's internal processes could also

significantly boost the case for future

missions to the distant planet. The

National Academy of Sciences had already

flagged a mission concept called the Uranus

Orbiter and Probe, or uop, as a high

priority for the next decade. These new

results showing how Uranus stores and loses

heat not only deepen our understanding of

this icy world, but also offer valuable

insights into fundamental

processes that shape planetary

atmospheres, weather systems, and even

climate systems. It's groundbreaking science

that could inform our studies of Earth's own

changing climate.

And that brings us to the end of another

fascinating episode of Astronomy Daily.

Thank you so much for tuning in and joining

me on this cosmic exploration. I'm Anna,

and it's been a pleasure sharing the latest

in space and astronomy news with you.

Remember, you can catch up on all the latest

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