A New View of the Milky Way, Akatsuki's Legacy, and How to Spot Comet Lemmon

0:00 Avery: Welcome to Astronomy Daily, the podcast that

0:02 brings you the universe one story at a time.

0:05 I'm Avery.

0:06 Anna: And I'm Anna. It's great to be with you

0:09 today. Today we have a packed show.

0:12 We'll be looking at a stunning new image of

0:14 our own Milky Way, saying a, ah, fond

0:17 farewell to a Venus orbiter and telling you

0:20 how to spot a comet visiting our skies.

0:23 Avery: Plus, we'll cover China's ambitious plans for

0:25 the Moon.

0:26 Anna: And.

0:26 Avery: And a fascinating discovery about the very

0:28 first stars in the universe were born. So

0:31 let's jump right in.

0:32 Anna, where are we starting?

0:34 Anna: Let's start close to home, Avery. With

0:37 a view of our galaxy like we've never seen

0:39 before. Astronomers have just released a

0:42 milestone new image of the Milky Way, and

0:45 it's absolutely breathtaking.

0:47 Avery: I've seen it, and it really is something

0:49 else. This isn't a typical photograph,

0:52 though, is it? This was captured using a

0:54 radio telescope array in Western Australia.

0:57 Anna: That's right. It's a low frequency

1:00 radio image from the Murchison Wide Field

1:02 Array. Think of it as seeing the galaxy in a

1:05 completely different kind of light. Instead

1:08 of starlight, we're seeing the radio waves

1:10 emitted by cosmic rays, hot gas, and

1:14 other energetic phenomena.

1:16 Avery: So it peels back the curtain in a way. The

1:19 dust clouds that block our view in visible

1:21 light are transparent to these radio waves,

1:23 right?

1:24 Anna: Exactly. This new survey gives us an

1:27 unprecedented view of the entire southern

1:30 galactic plane. For the first time, we have

1:33 a deep, wide image at these low

1:35 frequencies. And the level of detail is

1:38 incredible. The team has been able to catalog

1:41 over 3,000 supernova remnants,

1:44 the expanding shells of exploded stars.

1:47 Avery: 3,000. That's a huge jump in our census

1:50 of stellar deaths. And it's not just about

1:53 endings, is it? It also shows us where new

1:55 star born.

1:56 Anna: It does. We can see stellar

1:59 nurseries, vast clouds of gas and dust that

2:02 are just beginning to collapse and form new

2:05 suns and planets. By studying the galaxy

2:07 in this way, we can better understand the

2:10 entire life cycle of stars, from birth

2:13 in these nurseries to their often

2:16 violent deaths as supernovae. It's a

2:18 true milestone for radio astronomy.

2:21 Avery: Incredible. From the life of stars to the end

2:24 of a mission.

2:26 On a more somber note, we have to say goodbye

2:28 to a very tenacious spacecraft.

2:30 Anna: Yes, unfortunately,

2:33 jaxa, the Japanese space agency,

2:35 has officially declared its Akatsuki

2:38 spacecraft as dead. It was orbiting Venus,

2:41 and for a while, it was the only active

2:43 mission at our sister planet.

2:45 Avery: I remember its story. It had such a dramatic

2:48 journey. It didn't make it into orbit on the

2:51 first try. Did it?

2:52 Anna: Not at all. Its main engine failed during

2:55 the orbital insertion burn back in 2010

2:58 and flew right past Venus. The team

3:01 had to put it into a holding pattern,

3:03 orbiting the sun for five years. Then,

3:05 in a brilliant feat of engineering, they used

3:08 its smaller thrusters to make a second

3:11 successful attempt to enter orbit in 2015.

3:15 Avery: Just an amazing comeback story for a robotic

3:17 probe. And it delivered some fantastic

3:20 science for nearly a decade after that.

3:22 Anna: It really did. Akatsuki

3:25 completely revolutionized our understanding

3:27 of Venus's climate. Its biggest contribution

3:30 was studying the planet's super

3:32 rotation, a phenomenon where the atmosphere

3:35 whips around the planet 60 times faster

3:38 than the planet itself rotates. The probe's

3:41 infrared cameras tracked cloud movements and

3:43 helped us understand the dynamics driving

3:46 those extreme winds.

3:47 Avery: A, true testament to the ingenuity of its

3:50 mission controllers. It's sad to see it go,

3:52 and it leaves a temporary void in our

3:54 exploration of Venus.

3:56 Anna: It is.

3:57 But let's turn from a world we can't visit

4:00 to a visitor you can see in our own skies.

4:03 Avery, it's comet watching season.

4:06 Avery: It certainly is. Observers in the Northern

4:09 Hemisphere have a chance to spot Comet C

4:11 2025 A6, also known as

4:14 Comet Lemmon. It's currently making its way

4:17 through the inner solar system and is putting

4:19 on a nice little show.

4:20 Anna: So how can our listeners find it?

4:22 Avery: The best time to look is shortly after

4:24 sunset. You'll want to find a spot with a

4:26 clear view of the western horizon, away from

4:29 city lights, if you can. It made its closest

4:31 approach to Earth on October 21, and

4:34 it will reach its closest point to the sun on

4:36 November eight. So it's right in its prime

4:39 viewing window.

4:39 Anna: Now, will you need a telescope?

4:42 Avery: It might just be bright enough to be visible

4:44 to the naked eye under very dark skies,

4:47 but a good pair of binoculars is your best

4:49 bet. You'll be looking for a small, fuzzy

4:52 patch of light, maybe with a fake tail.

4:55 Anna: And this is a special visitor.

4:57 Comet LEMMON is a long period comet, which

5:00 means it comes from the Oort Cloud, the most

5:03 distant and icy region of our solar system.

5:06 And after it rounds the sun, it's going to be

5:09 flung back out into.

5:10 Avery: Deep space, and it won't be back for

5:13 another 1154

5:16 years. So, as you said, Anna, this is your

5:18 one and only chance to see it. Don't miss it.

5:21 Anna: From a fleeting visitor to a more permanent

5:24 destination. The world's space agencies

5:27 are looking to the future, and a big part of

5:30 that future is a return to the Moon.

5:33 Avery: That's right. And this week, China reiterated

5:35 its Ambitious goal to land their astronauts

5:37 on the lunar surface by 2030. Officials

5:40 confirmed that everything is moving forward

5:43 on schedule.

5:44 Anna: This isn't just talk. They're developing some

5:47 serious hardware. They mentioned that the new

5:50 super heavy lift rocket, the long March

5:52 10th is progressing smoothly. That's the

5:55 rocket powerful enough to send the crew and

5:58 lander to the moon.

5:59 Avery: They also said the development of the lander

6:02 itself, the lunar rover and the new moon

6:04 landing suits are all well underway. The

6:07 announcement came at ah, the same time they

6:08 introduced the next crew heading to their

6:10 Tiangong Space Station, which really

6:13 highlights how their human spaceflight

6:14 program is operating at a very high tempo.

6:17 The crew for China's next manned flight to

6:19 the Tiangong Space Station will include the

6:21 country's youngest ever astronaut to

6:24 undertake a space mission, as well as four

6:26 lab mice.

6:28 Anna: The Shenzhou 21 mission is set to blast

6:30 off at 11:44pm M on Friday

6:34 15:44 GMT from the Zhuquan

6:37 Satellite Launch center in northwest China.

6:40 Avery: This crew will be led by veteran space pilot

6:42 Zhang Liu, who took part in the Shenzhou 15

6:45 mission more than two years ago. He will lead

6:48 payload specialist Zhang Hongsheng and flight

6:51 engineer Wu Fei on their first space flight.

6:54 Anna: Wu, who has just turned 32, is

6:57 set to become the youngest Chinese astronaut

7:00 to undertake a space mission to date.

7:03 Avery: Also along for the ride are four mice, two

7:06 male and two female, which will be the

7:08 subjects of China's first in orbit

7:11 experiments on rodents.

7:12 Anna: It certainly feels like we're entering a new

7:15 era of lunar exploration with multiple

7:18 countries aiming for the Moon this decade.

7:20 It's going to be a very exciting few years.

7:23 Avery: Definitely.

7:24 For our final story, Anna, let's go from the

7:26 future of spaceflight to the most distant

7:29 past, all the way back to the universe's

7:31 cosmic dawn.

7:32 Anna: It's a fascinating story. A new study is

7:35 providing strong evidence that the very first

7:38 stars in the UniverseWhat astronomers call

7:41 Population 3 stars were commonly

7:44 born in pairs.

7:46 Avery: Born in pairs? That's incredible. How on

7:48 Earth can astronomers figure that out,

7:51 looking back over 13 billion years?

7:53 Anna: Well, we can't observe those first stars

7:56 directly. They were too massive and short

7:58 lived. So scientists have to be clever.

8:01 They used the Very Large Telescope in Chile

8:04 to study stars in the Small Magellanic Cloud,

8:07 a nearby dwarf galaxy.

8:09 Avery: Okay, but how does that help? Those aren't

8:12 population three stars.

8:14 Anna: They aren't. But the Small Magellanic Cloud

8:17 has very low metallicity. That's

8:20 the astronomical term for any element heavier

8:22 than hydrogen and helium. Its chemical

8:25 environment is much closer to the pristine

8:28 conditions of the early universe than our own

8:30 Milky Way is.

8:31 Avery: So these stars are like a local analog, a

8:34 window into how stars formed when heavy

8:37 elements were scarce.

8:38 Anna: Precisely. And what the researchers found

8:41 was striking. By observing the most

8:44 massive stars in this low metallicity

8:46 environment, they discovered that at least

8:49 70% of them are in close

8:52 binary systems orbiting a, companion

8:55 star.

8:56 Avery: Wow. 70%. That's not

8:59 a coincidence.

9:00 Anna: Not at all. It provides the

9:03 strongest observational evidence to date

9:06 that the first massive stars in the universe

9:09 were also primarily born as twins

9:12 or in multiple star systems.

9:15 This has huge implications for

9:17 understanding how early galaxies evolved,

9:20 how the first black holes were formed, and

9:23 how the universe was seeded with the heavy

9:25 elements that eventually made life like us

9:28 possible.

9:29 Avery: A, truly fundamental discovery.

9:32 And that's all the time we have for this

9:34 episode of Astronomy Daily. From our own

9:37 galactic backyard to the dawn of time, it's

9:39 been another busy week in the cosmos.

9:42 Anna: It certainly has. Thank you so much for

9:45 joining us. We'll be back next time with more

9:47 of the latest news from across the universe.

9:50 Avery: Until then, this is Avery reminding you to

9:53 keep looking up