- Euclid Space Telescope's Groundbreaking Findings: The European Space Agency's Euclid mission is revolutionizing our understanding of galaxy evolution just a year into its operations. With the capability to observe over 1.2 million galaxies, Euclid is addressing fundamental questions about galaxy shapes and their formation history, paving the way for a modern galactic tuning fork diagram.
- The Spectacular Geminid Meteor Shower: The Geminid meteor shower is set to peak on December 13th and 14th, promising a dazzling display of bright and colorful meteors. With a waning crescent moon providing optimal viewing conditions, it's the perfect opportunity to witness this annual celestial event.
- Near Earth Asteroids Close Approaches: This week, several near-Earth asteroids will make close passes to our planet, including 2025 VP1, a bus-sized asteroid, and the larger 3361 Orpheus, which is about 1,400 feet wide. While classified as potentially hazardous, their trajectories are closely monitored, ensuring no immediate threat to Earth.
- Runaway Stars and the Large Magellanic Cloud: New research utilizing hypervelocity stars sheds light on the history of the Large Magellanic Cloud. By tracing the paths of stars ejected by a supermassive black hole, scientists gather evidence that could confirm its existence and provide insights into the galaxy's past.
- Andromeda's Satellite Galaxies: A study from Durham University reveals how Andromeda's satellite galaxies are quenched, revealing that many lose their star-forming capabilities long before they even approach Andromeda. This highlights the complex interactions within our cosmic neighborhood.
- For more cosmic updates, visit our website at astronomydaily.io. Join our community on social media by searching for #AstroDailyPod on Facebook, X, YouTubeMusic, TikTok, and our new Instagram account! Don’t forget to subscribe to the podcast on Apple Podcasts, Spotify, iHeartRadio, or wherever you get your podcasts.
- Thank you for tuning in. This is Anna and Avery signing off. Until next time, keep looking up and exploring the wonders of our universe.
Euclid Mission Insights
[European Space Agency](https://www.esa.int/)
Geminid Meteor Shower Details
[NASA](https://www.nasa.gov/)
Near Earth Asteroids Overview
[NASA](https://www.nasa.gov/near-earth-objects)
Runaway Stars Research
[Harvard Center for Astrophysics](https://www.cfa.harvard.edu/)
Andromeda Satellite Galaxies Study
[Durham University](https://www.dur.ac.uk/)
Become a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-space-news-updates--5648921/support.
Sponsor Details:
Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.bitesz.com/nordvpn. You'll be glad you did!
Sponsor Details:
Ensure your online privacy by using NordVPN. To get our special listener deal and save a lot of money, visit www.bitesz.com/nordvpn. You'll be glad you did!
Become a supporter of Astronomy Daily by joining our Supporters Club. Commercial free episodes daily are only a click way... Click Here
This episode includes AI-generated content.
00:00:00 --> 00:00:02 Anna: Welcome to Astronomy Daily, the
00:00:02 --> 00:00:05 podcast that brings you the universe one
00:00:05 --> 00:00:08 story at a time. I'm Anna.
00:00:08 --> 00:00:10 Avery: And I'm Avery. It's great to have you with
00:00:10 --> 00:00:13 us. We've got a packed episode today, from a
00:00:13 --> 00:00:15 revolutionary space telescope rewriting
00:00:15 --> 00:00:18 galaxy evolution to a spectacular meteor
00:00:18 --> 00:00:20 shower you won't want to miss.
00:00:20 --> 00:00:23 Anna: Plus, we'll track some near Earth asteroids,
00:00:23 --> 00:00:26 chase runaway stars from a neighboring
00:00:26 --> 00:00:29 galaxy, and dive into the dramatic
00:00:29 --> 00:00:31 lives and deaths of Andromeda's small,
00:00:32 --> 00:00:33 smallest companion.
00:00:33 --> 00:00:35 Avery: A lot to cover, so let's get started.
00:00:36 --> 00:00:39 First up, the Euclid Space Telescope. This
00:00:39 --> 00:00:41 is genuinely exciting stuff. The European
00:00:41 --> 00:00:44 Space Agency's Euclid mission is only a year
00:00:44 --> 00:00:46 into its operations, but it's already
00:00:46 --> 00:00:48 delivering incredible insights.
00:00:49 --> 00:00:51 Anna: Right. It's tackling one of the biggest
00:00:51 --> 00:00:54 questions in why do
00:00:54 --> 00:00:56 galaxies have different shapes? And how do
00:00:56 --> 00:00:57 those shapes evolve?
00:00:58 --> 00:01:00 Avery: And the scale is just staggering.
00:01:01 --> 00:01:03 Euclid has already observed 1.2
00:01:03 --> 00:01:06 million galaxies with the first data dropping
00:01:06 --> 00:01:09 in March of 2025. By the end of
00:01:09 --> 00:01:11 its six year mission, they're expecting to
00:01:11 --> 00:01:13 study tens of millions.
00:01:13 --> 00:01:16 Anna: That's mind boggling. It gives them a
00:01:16 --> 00:01:19 huge statistical sample to work with. I
00:01:19 --> 00:01:22 saw a great quote from Maximilian Fabricius
00:01:22 --> 00:01:25 at the Max Planck Institute. He said Euclid
00:01:25 --> 00:01:28 offers an unprecedented combination of
00:01:28 --> 00:01:29 sharpness and sky.
00:01:30 --> 00:01:32 Avery: Exactly. For the first time, they can
00:01:32 --> 00:01:34 systematically study how a, uh, galaxy's
00:01:34 --> 00:01:37 shape relates to its formation history on a
00:01:37 --> 00:01:39 truly cosmic scale.
00:01:39 --> 00:01:42 Anna: And they're already using this data to build
00:01:42 --> 00:01:44 a modern galactic tuning fork diagram.
00:01:45 --> 00:01:48 It beautifully illustrates the life cycle of
00:01:48 --> 00:01:48 galaxies.
00:01:49 --> 00:01:50 Avery: Can you walk us through that?
00:01:50 --> 00:01:53 Anna: Of course. On one side, you have these
00:01:53 --> 00:01:56 vibrant blue star forming galaxies,
00:01:56 --> 00:01:59 like spirals. As they age, they
00:01:59 --> 00:02:01 exhaust their gas, they merge with
00:02:02 --> 00:02:04 other galaxies, and they slowly drift
00:02:04 --> 00:02:07 across the diagram, eventually becoming
00:02:07 --> 00:02:10 massive, featureless elliptical galaxies.
00:02:10 --> 00:02:13 Avery: So it's a visual timeline of galactic
00:02:13 --> 00:02:13 life.
00:02:14 --> 00:02:17 Anna: Precisely. And one of the key drivers of
00:02:17 --> 00:02:20 that change is mergers. Euclid's data
00:02:20 --> 00:02:22 is helping scientists spot galaxies with
00:02:23 --> 00:02:24 secondary nuclei.
00:02:24 --> 00:02:27 Avery: Right. So two galactic cores in the
00:02:27 --> 00:02:29 process of merging.
00:02:29 --> 00:02:32 Anna: Exactly. Each of those nuclei has its
00:02:32 --> 00:02:34 own supermassive black hole,
00:02:34 --> 00:02:37 millions or even billions of times the
00:02:37 --> 00:02:40 mass of our Sun. When the galaxies merge,
00:02:40 --> 00:02:42 those black holes are brought together.
00:02:43 --> 00:02:45 Avery: They form a binary system. Right. Spiraling
00:02:45 --> 00:02:46 around each other.
00:02:46 --> 00:02:49 Anna: Mhm. And as they do, they shed
00:02:49 --> 00:02:52 energy by creating gravitational waves,
00:02:53 --> 00:02:56 ripples in spacetime itself. This
00:02:56 --> 00:02:58 causes them to spiral closer and
00:02:58 --> 00:03:00 closer until they collide and
00:03:00 --> 00:03:03 merge into an even more massive black
00:03:03 --> 00:03:04 hole.
00:03:04 --> 00:03:06 Avery: So the growth of these giant elliptical
00:03:06 --> 00:03:08 galaxies and the growth of their central
00:03:08 --> 00:03:11 black holes are directly linked.
00:03:11 --> 00:03:14 Anna: They're inseparable It's a fundamental part
00:03:14 --> 00:03:17 of the process. But what's also fascinating
00:03:17 --> 00:03:20 is what Euclid is seeing at the other end of
00:03:20 --> 00:03:20 the scale.
00:03:21 --> 00:03:22 Avery: The dwarf galaxies.
00:03:22 --> 00:03:25 Anna: Yes, it turns out the most common
00:03:25 --> 00:03:27 galaxies in the universe aren't giant giants
00:03:27 --> 00:03:30 like our Milky Way, but these small, faint
00:03:30 --> 00:03:33 dwarf galaxies that were too dim to see
00:03:33 --> 00:03:36 clearly before. Euclid has already found
00:03:36 --> 00:03:38 over 2 of them.
00:03:38 --> 00:03:40 Avery: And those are important because they're
00:03:40 --> 00:03:43 considered the building blocks for larger
00:03:43 --> 00:03:43 galaxies.
00:03:43 --> 00:03:46 Anna: It's like we're finally seeing the cosmic
00:03:46 --> 00:03:49 bricks that build the great galactic cities.
00:03:49 --> 00:03:52 It's a total game changer for understanding.
00:03:52 --> 00:03:55 Avery: Galaxy evolution from the cosmic scale
00:03:55 --> 00:03:57 to something you can see in your own
00:03:57 --> 00:03:57 backyard.
00:03:58 --> 00:04:00 Let's talk about the Geminid meteor shower.
00:04:00 --> 00:04:02 It's one of the best shows of the year, and
00:04:02 --> 00:04:04 it's happening right now.
00:04:04 --> 00:04:07 Anna: And this year is set to be particularly good.
00:04:07 --> 00:04:10 The shower peaks on the night of December
00:04:10 --> 00:04:12 13th into the morning of the 14th,
00:04:12 --> 00:04:15 and the moon will be a waning crescent, so
00:04:15 --> 00:04:17 its light won't wash out the meteors.
00:04:18 --> 00:04:20 Avery: That's perfect timing. So when's the best
00:04:20 --> 00:04:21 time to head out?
00:04:21 --> 00:04:24 Anna: NASA recommends watching after midnight,
00:04:24 --> 00:04:26 wherever you are. That's when the radiant
00:04:26 --> 00:04:29 point, the spot in the constellation Gemini
00:04:29 --> 00:04:32 where the meteors appear to originate, is
00:04:32 --> 00:04:33 highest in the sky.
00:04:33 --> 00:04:35 Avery: And the usual advice applies. Get away from
00:04:35 --> 00:04:38 city lights, find a dark spot, and just give
00:04:38 --> 00:04:40 your eyes time to adjust.
00:04:40 --> 00:04:43 Anna: Right. What I love about the Geminids is
00:04:43 --> 00:04:45 their unusual origin. Most
00:04:45 --> 00:04:48 meteor showers come from the icy debris left
00:04:48 --> 00:04:49 by comets.
00:04:50 --> 00:04:52 Avery: But the Geminites are different. They come
00:04:52 --> 00:04:54 from an asteroid named 3200 Phaeton.
00:04:55 --> 00:04:57 Anna: It's a very strange object. It has
00:04:57 --> 00:05:00 an orbit that takes it incredibly close to
00:05:00 --> 00:05:03 the sun, which causes it to shed rocky dust
00:05:03 --> 00:05:05 and particles, almost like a comet.
00:05:06 --> 00:05:09 When Earth passes through that debris stream,
00:05:09 --> 00:05:10 we get the meteor shower.
00:05:10 --> 00:05:13 Avery: And because the particles are rocky bits of
00:05:13 --> 00:05:15 an asteroid rather than fluffy eyes from a
00:05:15 --> 00:05:17 comet, the meteors are different, aren't
00:05:17 --> 00:05:18 they?
00:05:18 --> 00:05:21 Anna: They are. Geminid meteors are often
00:05:21 --> 00:05:24 brighter, faster, and can leave these
00:05:24 --> 00:05:26 beautiful, long lasting, colorful streaks
00:05:26 --> 00:05:29 across the sky. It's a truly spectacular
00:05:29 --> 00:05:30 sight.
00:05:30 --> 00:05:32 Avery: Well, speaking of rocks flying through space,
00:05:32 --> 00:05:35 it's a busy week for near Earth asteroids.
00:05:35 --> 00:05:37 And while none of them pose a threat, their
00:05:37 --> 00:05:39 close approaches are always worth noting.
00:05:40 --> 00:05:42 Anna: Right. First up is an asteroid
00:05:42 --> 00:05:45 designated 2025 VP1.
00:05:46 --> 00:05:48 It's about the size of a bus, roughly
00:05:48 --> 00:05:51 37ft in diameter, and it's passing.
00:05:51 --> 00:05:54 Avery: Within 361 miles from
00:05:54 --> 00:05:56 Earth. That's closer than the Moon.
00:05:56 --> 00:05:59 Anna: It is. But to be clear, that's
00:05:59 --> 00:06:02 still a Very safe distance. There's no danger
00:06:02 --> 00:06:04 of impact at all. It's more of a great
00:06:04 --> 00:06:07 opportunity for scientists to study these
00:06:07 --> 00:06:08 smaller Near Earth objects.
00:06:09 --> 00:06:11 Avery: And it's not alone. There's another one of a
00:06:11 --> 00:06:13 similar size, 2025 VC4,
00:06:14 --> 00:06:16 passing a bit further out at about 1.24
00:06:16 --> 00:06:17 million miles.
00:06:17 --> 00:06:20 Anna: Mhm. But the big one this week is
00:06:20 --> 00:06:22 3361 Orpheus.
00:06:23 --> 00:06:25 Avery: Big is an understatement. This one is about
00:06:25 --> 00:06:28 1400ft wide. That's approximately
00:06:28 --> 00:06:31 426 meters, which is roughly the
00:06:31 --> 00:06:32 size of the Empire State Building.
00:06:33 --> 00:06:35 Anna: That is a significant object. It's
00:06:35 --> 00:06:38 traveling at 20 miles per hour,
00:06:38 --> 00:06:41 but again passing at a safe distance.
00:06:42 --> 00:06:44 However, its size is what gets it special
00:06:44 --> 00:06:44 attention.
00:06:45 --> 00:06:47 Avery: Right. It's classified as a potentially
00:06:47 --> 00:06:50 hazardous asteroid or pha.
00:06:50 --> 00:06:52 Anna: And that term can sound alarming, but it's
00:06:52 --> 00:06:55 really just a classification. It doesn't mean
00:06:55 --> 00:06:57 it's an immediate threat.
00:06:57 --> 00:06:58 Avery: So what does it mean?
00:06:59 --> 00:07:02 Anna: A uh, Pha is any asteroid larger than
00:07:02 --> 00:07:04 about 460ft that comes within
00:07:04 --> 00:07:07 4.6 million miles of Earth's
00:07:07 --> 00:07:09 orbit. Orpheus fits that definition.
00:07:10 --> 00:07:12 So its trajectory is very closely monitored
00:07:12 --> 00:07:15 by NASA just to be safe. It's cosmic
00:07:15 --> 00:07:18 due diligence from objects passing.
00:07:18 --> 00:07:20 Avery: By our planet to objects being violently
00:07:20 --> 00:07:22 thrown out of their own galaxies. There's a
00:07:22 --> 00:07:25 fascinating new paper that uses runaway stars
00:07:25 --> 00:07:28 to solve a long standing mystery about one of
00:07:28 --> 00:07:29 our nearest neighbors.
00:07:29 --> 00:07:32 Anna: You're talking about the Large Magellanic
00:07:32 --> 00:07:35 Cloud, the lmc. For decades
00:07:35 --> 00:07:37 astronomers have debated the exact path it's
00:07:37 --> 00:07:40 taken through space over the last few billion
00:07:40 --> 00:07:40 years.
00:07:40 --> 00:07:43 Avery: Exactly. And researchers at the Harvard
00:07:43 --> 00:07:45 center for Astrophysics have come up with a
00:07:45 --> 00:07:48 brilliant way to trace its history by using
00:07:48 --> 00:07:50 hypervelocity stars.
00:07:50 --> 00:07:53 Anna: These are stars moving at incredibly
00:07:53 --> 00:07:54 speeds. Right.
00:07:54 --> 00:07:57 Avery: Incredible is the word. We're talking over
00:07:57 --> 00:07:59 1 kilometers per second, which is over 2
00:07:59 --> 00:08:02 million miles per hour. Fast enough to
00:08:02 --> 00:08:04 eventually escape their home galaxy entirely.
00:08:05 --> 00:08:07 Anna: And we think they get that speed boost from a
00:08:07 --> 00:08:09 ah, gravitational slingshot.
00:08:09 --> 00:08:12 Avery: That's the theory. It happens when a binary
00:08:12 --> 00:08:14 star system, two stars orbiting each other,
00:08:14 --> 00:08:17 gets too close to a supermassive black
00:08:17 --> 00:08:20 hole. The black hole's immense gravity rips
00:08:20 --> 00:08:21 the binary apart.
00:08:21 --> 00:08:24 Anna: Mhm. One star gets captured into a tight
00:08:24 --> 00:08:27 orbit around the black hole and the.
00:08:27 --> 00:08:29 Avery: Other is ejected with tremendous force
00:08:30 --> 00:08:32 flung out into intergalactic space. A
00:08:32 --> 00:08:33 runaway star.
00:08:34 --> 00:08:36 Anna: So the researchers went looking for these in
00:08:36 --> 00:08:38 data from the Gaia Space Telescope.
00:08:38 --> 00:08:41 Avery: They did. They combed through the data and
00:08:41 --> 00:08:42 found three stars that they are confident
00:08:42 --> 00:08:45 were ejected from the Large Magellanic Cloud.
00:08:46 --> 00:08:48 Anna: And that's a huge clue. If you can trace the
00:08:48 --> 00:08:51 paths of those stars backward, they should
00:08:51 --> 00:08:51 all point.
00:08:51 --> 00:08:54 Avery: To their origin, the supermassive black hole
00:08:54 --> 00:08:57 that kicked them out. This is a big deal
00:08:57 --> 00:08:59 because there's still debate about whether
00:08:59 --> 00:09:01 the LMC even has a supermassive black hole
00:09:01 --> 00:09:02 at its center.
00:09:03 --> 00:09:05 Anna: Right? So this provides strong indirect
00:09:05 --> 00:09:08 evidence that it does. And more importantly,
00:09:08 --> 00:09:10 it tells astronomers exactly where to point
00:09:10 --> 00:09:12 their telescopes to look for direct proof.
00:09:13 --> 00:09:14 It's brilliant detective work.
00:09:15 --> 00:09:17 Avery: This idea of galactic interactions is a
00:09:17 --> 00:09:20 perfect lead in to our final story, which
00:09:20 --> 00:09:21 looks at our other famous neighbor, the
00:09:21 --> 00:09:22 Andromeda galaxy.
00:09:23 --> 00:09:25 We know galaxies grow by emerging and
00:09:25 --> 00:09:26 consuming smaller ones.
00:09:27 --> 00:09:29 Anna: We can see it happening in real time. Our own
00:09:29 --> 00:09:31 Milky Way is currently stripping gas from the
00:09:31 --> 00:09:34 Large and Small Magellanic Clouds, right?
00:09:34 --> 00:09:37 Avery: Creating that enormous 600 light year
00:09:37 --> 00:09:39 long feature called the Magellanic Stream.
00:09:39 --> 00:09:42 Anna: It's a gravitational tug of war. And the much
00:09:42 --> 00:09:44 more massive Milky Way is winning.
00:09:44 --> 00:09:47 Andromeda is doing the same thing with its
00:09:47 --> 00:09:49 own suite of satellite dwarf galaxies.
00:09:49 --> 00:09:51 Avery: And new research from Durham University has
00:09:51 --> 00:09:54 been looking at how that process unfolds.
00:09:54 --> 00:09:56 Specifically, they're studying how these
00:09:56 --> 00:09:58 satellite galaxies are quenched.
00:09:58 --> 00:10:01 Anna: Quenching is when a galaxy stops forming new
00:10:01 --> 00:10:03 stars, it essentially runs out of the cold
00:10:03 --> 00:10:06 gas it needs to do so. And its star birthing
00:10:06 --> 00:10:07 days are over.
00:10:08 --> 00:10:10 Avery: And the results from Andromeda are quite
00:10:10 --> 00:10:12 stark. The research shows that only the most
00:10:12 --> 00:10:15 massive satellite galaxies are able to keep
00:10:15 --> 00:10:17 forming stars for more than 3 billion years
00:10:17 --> 00:10:20 after their closest approach to Andromeda.
00:10:20 --> 00:10:22 Anna: That close approach is called the Paracenter,
00:10:22 --> 00:10:24 and it's a brutal experience for a small
00:10:24 --> 00:10:27 galaxy. The immense gravity of Andromeda
00:10:27 --> 00:10:30 tidally strips away its gas. And a process
00:10:30 --> 00:10:32 called ram pressure stripping acts like a
00:10:32 --> 00:10:34 cosmic window blowing the gas out.
00:10:35 --> 00:10:37 Avery: So the little guys just can't hold on to
00:10:37 --> 00:10:38 their star forming fuel.
00:10:38 --> 00:10:41 Anna: Exactly. But what's really interesting is
00:10:41 --> 00:10:43 that many of the least massive satellites
00:10:43 --> 00:10:46 appear to have been quenched long before they
00:10:46 --> 00:10:48 even got close to Andromeda, some as much as
00:10:48 --> 00:10:50 10 billion years prior.
00:10:50 --> 00:10:51 Avery: How does that happen?
00:10:52 --> 00:10:55 Anna: The researchers call it pre processing. The
00:10:55 --> 00:10:57 idea is that before a dwarf galaxy fell into
00:10:57 --> 00:10:59 Andromeda's orbit, it might have been a
00:10:59 --> 00:11:01 satellite of a different, slightly larger
00:11:01 --> 00:11:04 galaxy. The that earlier encounter was enough
00:11:04 --> 00:11:05 to remove its gas and quench it.
00:11:06 --> 00:11:08 Avery: So it was already a galactic ghost by the
00:11:08 --> 00:11:10 time it met Andromeda.
00:11:10 --> 00:11:12 Anna: In a sense, yes. And when the researchers
00:11:12 --> 00:11:15 compared Andromeda's satellites to the Milky
00:11:15 --> 00:11:17 Ways, they found a difference. Our satellites
00:11:17 --> 00:11:19 seem to have been captured earlier and
00:11:19 --> 00:11:22 quenched more quickly. It suggests our galaxy
00:11:22 --> 00:11:24 might have been a more aggressive consumer in
00:11:24 --> 00:11:26 its past than Andromeda was.
00:11:26 --> 00:11:29 Avery: It really paints a picture of a dynamic and
00:11:29 --> 00:11:32 sometimes violent cosmic ecosystem. A
00:11:32 --> 00:11:34 fascinating look at the lives and deaths of
00:11:34 --> 00:11:34 galaxies.
00:11:35 --> 00:11:37 Anna: And that's all the time we have for today on
00:11:37 --> 00:11:40 Astronomy Daily. From the grand architecture
00:11:40 --> 00:11:42 of the universe revealed by Euclid to the
00:11:42 --> 00:11:44 fleeting beauty of a meteor shower, the
00:11:44 --> 00:11:46 cosmos never fails to inspire.
00:11:47 --> 00:11:49 Avery: Absolutely. It's a great reminder to look up
00:11:50 --> 00:11:52 if you get a chance this week, try and catch
00:11:52 --> 00:11:54 the Geminids. A clear, dark sky is all you
00:11:54 --> 00:11:55 need.
00:11:55 --> 00:11:57 Anna: Thanks for joining us. I'm Anna.
00:11:57 --> 00:11:59 Avery: And I'm Avery. Clear skies.