The Sun's Great Galactic Road Trip, China's Moon Museum & a Pi Day Planet

Dog grooming genius here. Most people see a busy dog salon, but I see operational excellence.

Thanks to genius, from global payments. Scheduling, personalized, checkouts, instant,

absolutely genius. From game day crowds to every groomer in this shop,

genius keeps everything flowing seamlessly. Flawless execution, big league reliability for

any business. That's genius. Hi, this is Alex Cantrowitz. I'm the host of Big Technology podcast,

a long time reporter and an on-air contributor to CNBC. And if you're like me, you're trying to

figure out how artificial intelligence is changing the business world and our lives. So each week

on Big Technology, I bring on key actors from companies building AI tech and outsiders trying

to influence it, asking where this is all going. They come from places like Nvidia, Microsoft,

Amazon, and plenty more. So if you want to be smart with your wallet, your career choices,

and meetings with your colleagues and at dinner parties, listen to Big Technology podcast

wherever you get your podcasts. Happy Pi Day Space Fans 3.14159 and counting. Yes, it's March 14th.

And if that sounds like an excuse to talk about an exoplanet with a 3.14-day year, that's because

it absolutely is. But before we get to our Cosmic Pi celebration, we have a packed episode.

A story about where our own son came from, a big announcement about where China's astronauts

might first set foot on the moon and Russia's bold plan to pick up where the Soviet Union left

off at Venus. Plus, a nuclear-powered flying drone for Saturn's moon Titan is now actually being

built. And China's race to beat everyone to a Martian soil sample is well and truly underway.

I'm Avery. And I'm Anna. This is Astronomy Daily, season 5, episode 63. Let's get into it.

Here's a question that sounds simple, but turns out to be surprisingly deep. How did our own

son end up where it is in the Milky Way? Right. I mean, you might assume it just formed where it is.

But the evidence has been pointing somewhere else for a while. And a new study published

this week in astronomy and astrophysics might finally have the answer. And it involves thousands

of stars traveling together. Researchers at Tokyo Metropolitan University and the National

Astronomical Observatory of Japan built the largest ever catalog of what are called solar twins.

Stars so similar to our son in temperature, mass, chemical composition, and surface gravity,

that they're essentially its cousins. They compiled 6,594 solar twins, which is a staggering

number when you think about how special we tend to think our son is. And they used Esa's

Gaia satellite data to determine two things about each star. How old it is and where it has been

moving. What they found was a striking pattern. A large number of these solar twins are between

4 and 6 billion years old, which is the same age bracket as our own son. That clustering is not

random. It suggests that the sun and many of these stars formed in the same general region of

the galaxy, probably closer to the Milky Way's inner regions, and then gradually drifted outward

together over billions of years. But here's the puzzle that the researchers had to solve.

The Milky Way has what's called a galactic bar, a rotating bar-shaped structure of stars

and gas near the center. That bar creates something astronomers call a co-rotation barrier,

which basically traps stars in certain orbital zones and makes it very hard for them to move

outward. So how did the sun escape? The theory is that when the sun and its companions formed,

the galactic bar was still in the process of forming. It wasn't fully developed yet. And the weaker

barrier may have allowed whole groups of stars to break out together, carried along by the dynamics

of the early galaxy. And the implications of this go beyond just knowing our son's origin story.

If the sun formed much closer to the center, researchers estimate about 10,000 light years closer

than it is today. Then this migration may actually be part of the reason Earth became habitable.

The galactic center is a harsher place, higher star density, more frequent supernova explosions,

more high energy radiation. Moving outward placed us in a calmer neighborhood,

one where complex chemistry and life could hold and persist over billions of years.

So our sun didn't travel alone. It was part of a wave, a kind of ancient stellar migration.

And that journey may be one of the reasons we are here to talk about it.

There is a lot to be grateful for in that story.

If you've been following the global moon race, you'll know that China has an ambitious target

to land astronauts on the lunar surface by 2030. And this week, we got the clearest picture

yet of where that landing might happen. A new study published in Nature Astronomy has highlighted

a region called Remi-Bode, a volcanic area near the lunar equator on the Moon's near side

as the leading candidate for China's first crude lunar mission.

And the description that researcher June Huang from the China University of Geosciences used for

it is just perfect. He called it a geological museum. Because within a relatively compact area,

Remi-Bode contains five distinct terrain types, ancient pyro-classic deposits from volcanic

eruptions, smooth Maurei basalts, two different real systems which are essentially long channels

or cracks in the surface, and nearby highland material. Five completely different chapters of

lunar history all accessible from one landing zone. That's the key point for mission planners.

A scientifically rich site is only useful if it's also safe and practical. And what makes Remi-Bode

attractive is that astronauts could potentially traverse across several very different geological

environments without having to travel enormous and risky distances. The researchers dated some of

the earliest volcanic activity in the region to roughly 3.2 to 3.7 billion years ago. That's deep

lunar history. And those ancient pyro-classic materials could include ash and glass beads thrown

up from the Moon's interior, which would be completely different from the rocks returned by the

Apollo missions or China's own robotic Chang'e missions. This site didn't come out of nowhere.

Chinese researchers had originally screened 106 potential landing areas and narrowed them to

14 candidates based on practical requirements, mere side location for communication with Earth,

access to solar power, and terrain safe enough for landing and surface operations.

From that short list, the new paper proposes four specific landing spots within Remi-Bode itself.

Each offering slightly different scientific priorities while still meeting those safety criteria.

The plan also includes the use of an unpressurized rover to travel between geological units,

which would dramatically extend the science possible in a single mission.

China's crude lunar program is part of a larger sequence that includes Chang'e 7 and Chang'e 8

missions, with long-term goals around a South Polar Research Station. But Remi-Bode as a first

landing site makes a lot of sense, mere side for communications, scientifically diverse,

and a manageable operating environment. It's still a candidate rather than a confirmed destination,

but this is the most specific and scientifically detailed case we've seen yet for where China's

first astronauts might set foot on another world. Another country making a big announcement this week.

Russia has announced plans to launch a mission called Venera D to Venus in 2036,

and it's an ambitious one. We're talking about a lander, a balloon that would float through the

Venetian atmosphere, and an orbiter, all working together. And the historical context here is remarkable.

The Soviet Union is the only nation in history to have successfully landed and operated spacecraft

on the surface of Venus. Venera 7 did it first, back in 1970, and over the following 13 years,

the Soviets sent a whole series of Venera landers and orbiters, 16 missions in total across 22 years.

And when you understand what the surface of Venus is actually like, that achievement becomes

even more extraordinary. Surface temperatures around 900 degrees Fahrenheit. That's 480 Celsius.

Atmospheric pressure, more than 90 times that of Earth at sea level. It is a genuinely hellish

environment. The Soviet Venera landers didn't just survive. They sent back images.

Those photographs of Venus' volcanic rock surface tinged yellow by the sulfuric acid clouds above

remain some of the most extraordinary images in the history of space exploration.

Russia hasn't been to Venus since 1983, and Venera D has actually been in planning since 2003.

It was at one point even under consideration as a joint mission with NASA,

before Russia's 2022 invasion of Ukraine ended that kind of collaboration.

Russia's first deputy prime minister, Dennis Monteroff, confirmed the mission this week,

describing Venus alongside the moon as central to Russia's space ambitions.

And one of the Naredes' key scientific goals will be searching for signs of microbial life in

Venus' clouds. That's not as outlandish as it might sound. The cloud layers of Venus at

altitudes of around 48 to 60 kilometers have temperatures and pressures not unlike those

at Earth's surface. And there have been disputed detections of phosphine and ammonia there,

both of which could potentially be biological in origin.

Russia isn't the only nation looking at Venus right now.

Esa's Envision Mission, India's Shukrayan-1,

and NASA's DaVinci and Veritas projects are all in various stages of development.

Venus is having a moment.

And if Finera D launches in 2036 as planned,

it would extend one of the most impressive and now largely forgotten legacies in space exploration

history. The Soviets conquered Venus. Russia wants to go back.

Now, here's a milestone that deserves a moment of appreciation.

This week, engineers at the Johns Hopkins Applied Physics Laboratory in Maryland

officially began assembling NASA's Dragonfly rotorcraft,

the nuclear power drone that will one day fly across the surface of Saturn's Moon Titan.

This is the point where a mission stops being a plan and starts being a physical thing.

Principal investigator Elizabeth Turtle put it perfectly when she said,

this milestone essentially marks the birth of our flight system.

So what is Dragonfly exactly? It's a car-sized eight-rotor drone.

Think of a very large quadcopter, but with eight rotors and four counter-rotating pairs.

It'll be powered not by solar energy, but by a radioisotope thermoelectric generator.

A nuclear power source, because sunlight on Titan is too faint and too inconsistent to be useful.

And Titan is just a spectacular target. It's Saturn's largest moon,

and it's unlike anywhere else we've thought about sending a mission.

It has a thick, nitrogen atmosphere,

denser than Earth's, which is actually what makes flying there possible.

It has rivers and lakes, but not of water, of liquid,

methane, and ethane. It has complex organic chemistry,

raining down from the atmosphere like a slow chemical snow.

Scientists think Titan's surface chemistry might resemble what Earth looked like before life emerged,

which is exactly why it's so exciting from an astrobiology perspective.

Dragonfly will fly to dozens of locations across the surface,

stopping to collect and analyze samples as it goes.

The first power and functional tests have already been completed on Dragonfly's

integrated electronics module, its brain, and its power switching units.

The arrow shell and cruise stage are being assembled at Lockheed Martin in Colorado,

and the wind tunnel testing at NASA Langley has already validated the rotor design.

The timeline? Integration and testing continues at Johns Hopkins through this year and into

early 2027, then system-level testing at Lockheed Martin, then final environmental testing back at

Hopkins before heading to Kennedy Space Center in spring of 2028 for launch on a SpaceX Falcon

Heavy that summer. Arrival at Titan 2034, and once there, Dragonfly aims to cover more than 108

miles of terrain, nearly double the total distance traveled by all Mars rovers combined.

It is one of the most audacious planetary missions ever conceived, and this week it became a real

spacecraft. More news from China. The race to return samples from Mars is very much on,

and this week came confirmation that China's entry in that race is moving from engineering

prototypes to real flight hardware. Chief designer Liu Ji Cheng announced at China's annual

two sessions political meetings on March 12th that Tianwen 3 has achieved breakthroughs in all

key technologies, and now is entering the flight model development phase, meaning they're building

the actual spacecraft that will go to Mars. Tianwen 3 is an enormously complex mission.

It involves two separate launches from Earth in late 2028, using Long March 5 rockets,

the same type that launched China's previous Mars mission and its lunar sample return.

One launch carries a lander and a sent vehicle, the other carries an orbiter and Earth-return

spacecraft. The lander touches down on Mars, collects at least 500 grams of Martian rock and

soil, using a combination of a scoop, a drill, and a small drone, then the sent vehicle launches

those samples into Mars orbit. There, it rendezvouses with the orbiter, which then carries the

samples all the way back to Earth, targeted arrival in 2031. If successful, that would make Tianwen

3 the first ever mission to return samples from Mars, and that's important context. NASA's own

Mars sample return program was effectively canceled earlier this year when it received no funding

in the 2026 appropriations bill. China has narrowed its landing site candidates from 106 down to 19,

with the final three to be selected by the end of this year. Candidate sites include ancient

shorelines, clay mineral-rich terrain that could preserve organic molecules, and areas associated

with Mars' ancient water systems. The primary scientific goal is the search for biosignatures,

potential signs that life once existed on Mars. The mission is also open to international

collaboration, with China inviting partner payloads and promising international scientists access

to the return samples. This is a story worth watching very closely. By the time Tianwen 3 launches

in 2028, it may well be the only active Mars sample return mission on the books. The first

Martian soil in a laboratory on Earth could be arriving on a Chinese spacecraft. We'll keep an

eye on this one. The geopolitical ramifications, not to mention bragging rights, could be quite

important. All right, we saved the best for Pi Day, and NASA's astronomy picture of the day

team clearly agrees with us, because today's APOD is dedicated entirely to K2-315b. The exoplanet

with a year that lasts almost exactly 3.14 days. K2-315b was discovered using data from the

Kepler Space Telescopes extended K2 mission and announced back in 2020. It's an Earth-sized

world orbiting a cool red dwarf star, an M-type star, about 185 light years away from us.

Now, an orbital period of 3.14 days means it is very close to its star, very close,

which means its surface temperature is absolutely scorching, the kind of baking hot that makes

any thoughts of habitability evaporate immediately. But that's fine. K2-315b is not here to be habitable,

it's here to be delightful. Because of all the exoplanets we found, and we found thousands now,

this one just happens to orbit its star in almost precisely Pi Days.

The precision is genuinely striking. Astronomers measured the orbital period at 3.14159 days,

which if you had your Pi memorized since school, you'll recognize as Pi to 5 decimal places.

The universe didn't do that on purpose, obviously, but it's a beautiful coincidence,

and a wonderful reminder that the cosmos doesn't always have to be profound and weighty.

Sometimes, it just gives you a planet that celebrates mathematics.

So, from all of us here at Astronomy Daily, happy Pi Day, may your circles be perfect and your

exoplanets be numerically satisfying. And that wraps up Episode 63 of Astronomy Daily Season 5.

What a show today! Solar Twin Migrations, China's Lunar Museum, Soviet-era Venus Nostalgia,

nuclear drones for Titan, the Mars sample race, and the Pi Day cosmic treat.

If you enjoyed today's episode, please leave us a review wherever you listen.

It genuinely makes a difference in helping new listeners find us and share the show with anyone

who needs a little more space in their life. You can find us at AstronomyDaily.io,

and we're at AstroDailyPod on X, Instagram, TikTok, YouTube, Facebook, and Tumblr.

All your show notes, links, and extras are on the website. We'll be back on Monday with more

of the universe's greatest hits. Until then, keep looking up.

AstronomyDaily, the star is the toe.

Hi, this is Alex Cantrowitz. I'm the host of Big Technology podcast, a long time reporter

and an on-air contributor to CNBC. And if you're like me, you're trying to figure out how

artificial intelligence is changing the business world and our lives. So each week on Big Technology,

I bring on key actors from companies building AI tech and outsiders trying to influence it.

Asking where this is all going, they come from places like Nvidia, Microsoft, Amazon,

and plenty more. So if you want to be smart with your wallet, your career choices,

and meetings with your colleagues and at dinner parties, listen to Big Technology podcast

wherever you get your podcasts. The sun shining birds are singing and all feels right in the world.

Until the season changes and suddenly you lose your motivation to get out of bed.

In fact, one in five people experience some form of depression no matter the season or time of year.

At the American Psychiatric Association Foundation, our vision is to build a mentally healthy

nation for all because we want you to live your best life and be your best you all year round.

Please visit mentallyhealthynation.org to learn more.