Welcome to Episode 60 of Astronomy Daily Season Five! In today's episode, Anna and Avery cover six major stories from the world of space and astronomy — including a neutron star collision in an unprecedented location, the latest Artemis II news, and a cosmic mystery solved after decades. Stories covered in this episode: 1. NASA Discovers Neutron Star Crash in Unexpected Location A fleet of NASA telescopes — including Chandra, Fermi, Swift, and Hubble — has detected a neutron star merger inside a tiny galaxy buried in a vast stream of gas, 4.7 billion light-years away. It's the first time this type of collision has been spotted in such an environment, and it may explain why gamma-ray bursts sometimes appear outside any galaxy — and how precious metals like gold and platinum ended up in distant stellar regions. Published in The Astrophysical Journal Letters. 2. Artemis II Flight Readiness Review NASA will host a Flight Readiness Review press conference on Thursday 12 March at Kennedy Space Center, covering progress toward the first crewed Artemis mission. The rocket is currently back in the Vehicle Assembly Building following a helium issue, with rollout to the launchpad expected around 19 March and a launch target of no earlier than 1 April 2026. 3. Firefly Alpha 'Stairway to Seven' Scrubbed Again Firefly Aerospace's Alpha rocket — attempting its return to flight after a 10-month grounding — has been scrubbed three times in 10 days. The latest scrub occurred on 10 March during fluid loading after off-nominal readings. A new launch date will be confirmed following engineering review. This mission is the final Block I Alpha flight, with the upgraded Block II debuting on Flight 8. 4. DART Mission Reveals 'Cosmic Snowball Fight' Between Asteroids Researchers at the University of Maryland have found the first direct visual proof of material transfer between two asteroids — fan-shaped streaks on the surface of asteroid moon Dimorphos, left by debris thrown off its parent asteroid Didymos at just 30.7 cm/s. The discovery provides visual confirmation of the YORP effect and has implications for planetary defence modelling. ESA's Hera mission arrives at Didymos in December 2026. Published in The Planetary Science Journal. 5. Starship Flight 12 — About Four Weeks Away SpaceX is approximately four weeks from the launch of Starship Flight 12, which will be the first flight of the upgraded V3 configuration — the most powerful version of the already record-breaking vehicle. Engineers have completed propellant system tests on Ship 39 at Starbase, Texas, and preflight preparations are continuing. 6. Giant Cosmic Sheet Discovered Around the Milky Way Astronomers from the University of Groningen, publishing in Nature Astronomy, have used advanced computer simulations to discover that the matter surrounding our Local Group is arranged in a vast, flat sheet — dominated by dark matter — stretching tens of millions of light-years across. This structure, flanked by enormous empty voids, explains why nearby galaxies are moving away from us rather than being pulled inward. It's the first detailed map of dark matter distribution in our cosmic neighbourhood.
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00:00:00 --> 00:00:02 Hello and welcome to Astronomy Daily,
00:00:02 --> 00:00:05 your daily dose of what's happening in
00:00:05 --> 00:00:07 the cosmos. I'm Avery.
00:00:07 --> 00:00:09 >> And I'm Anna. It is Wednesday, the 11th
00:00:10 --> 00:00:13 of March, 2026, and this is season 5,
00:00:13 --> 00:00:16 episode 60, which means 60 episodes of
00:00:16 --> 00:00:19 bringing you the universe, one day at a
00:00:19 --> 00:00:19 time.
00:00:20 --> 00:00:22 >> 60 episodes this year. That's a lot of
00:00:22 --> 00:00:25 space news. And today's lineup is not
00:00:25 --> 00:00:27 letting up. We've got neutron stars
00:00:27 --> 00:00:30 colliding in places nobody expected. A
00:00:30 --> 00:00:33 potential cosmic snowball fight between
00:00:33 --> 00:00:36 asteroids and a giant invisible sheet of
00:00:36 --> 00:00:38 dark matter that explains one of
00:00:38 --> 00:00:40 astronomy's longestr running mysteries.
00:00:40 --> 00:00:43 >> Plus, the latest on Artemis 2,
00:00:43 --> 00:00:46 Starship's next giant leap and a rocket
00:00:46 --> 00:00:48 that can't seem to get off the ground,
00:00:48 --> 00:00:50 but not for lack of trying.
00:00:50 --> 00:00:52 >> Stay with us. It's a big one. We start
00:00:52 --> 00:00:55 today with one of the most remarkable
00:00:55 --> 00:00:57 astronomy announcements in recent
00:00:57 --> 00:01:00 memory, and it literally involves gold.
00:01:00 --> 00:01:02 >> That's right. NASA has just published a
00:01:02 --> 00:01:05 major new finding. A fleet of its space
00:01:05 --> 00:01:07 telescopes has likely detected a
00:01:07 --> 00:01:10 collision between two neutron stars. And
00:01:10 --> 00:01:11 the location where this happened has
00:01:12 --> 00:01:13 stunned researchers.
00:01:13 --> 00:01:15 >> Though, let's back up for listeners who
00:01:15 --> 00:01:17 might not be familiar with neutron
00:01:17 --> 00:01:19 stars. These are the remnants left
00:01:19 --> 00:01:21 behind when a massive star burns out,
00:01:21 --> 00:01:24 collapses on itself, and explodes in a
00:01:24 --> 00:01:27 supernova. What's left is this tiny,
00:01:27 --> 00:01:30 unbelievably dense ball about the width
00:01:30 --> 00:01:32 of a city, but containing more mass than
00:01:32 --> 00:01:34 our entire sun.
00:01:34 --> 00:01:36 >> And when two of those collide, which is
00:01:36 --> 00:01:38 called a neutron star merger, it
00:01:38 --> 00:01:41 produces one of the most violent events
00:01:41 --> 00:01:43 in the universe. We're talking gamma ray
00:01:43 --> 00:01:46 bursts, gravitational waves rippling
00:01:46 --> 00:01:48 through spaceime, and something called a
00:01:48 --> 00:01:51 kilanova explosion. That's the process
00:01:51 --> 00:01:53 that forges heavy elements, things like
00:01:53 --> 00:01:55 gold, silver, and platinum through a
00:01:55 --> 00:01:58 chain of nuclear reactions that can't
00:01:58 --> 00:02:00 happen anywhere else in the cosmos.
00:02:00 --> 00:02:02 >> We've seen these mergers before, but
00:02:02 --> 00:02:05 always inside large or moderately sized
00:02:05 --> 00:02:07 galaxies. That's what makes this
00:02:07 --> 00:02:10 discovery so jaw-dropping. This one was
00:02:10 --> 00:02:13 found inside a tiny faint galaxy, barely
00:02:13 --> 00:02:16 there, tucked inside a vast stream of
00:02:16 --> 00:02:19 gas 4.7 billion lighty years away. A
00:02:19 --> 00:02:21 location nobody thought to look.
00:02:21 --> 00:02:24 >> The lead researcher, Simone Diara of
00:02:24 --> 00:02:26 Penn State University called it quote
00:02:26 --> 00:02:29 gamechanging, saying it may unlock not
00:02:29 --> 00:02:31 one but two important questions in
00:02:31 --> 00:02:34 astrophysics. One is why gamma ray
00:02:34 --> 00:02:36 bursts sometimes appear in the middle of
00:02:36 --> 00:02:39 nowhere, not near any galaxy at all. And
00:02:39 --> 00:02:41 the other is how precious metals ended
00:02:41 --> 00:02:44 up in stars at the very outer fringes of
00:02:44 --> 00:02:47 galaxies. The answer, it seems, is that
00:02:47 --> 00:02:49 small wandering galaxies like this one
00:02:49 --> 00:02:51 can form from the debris of larger
00:02:51 --> 00:02:53 galactic collisions and eventually
00:02:53 --> 00:02:56 produce their own neutron stars, which
00:02:56 --> 00:02:59 then merge. Co-author Eleanor Troya of
00:02:59 --> 00:03:01 the University of Rome put it
00:03:01 --> 00:03:03 beautifully. We found a collision within
00:03:03 --> 00:03:05 a collision. The galaxy collision
00:03:05 --> 00:03:08 triggered star formation which over
00:03:08 --> 00:03:10 hundreds of millions of years led to the
00:03:10 --> 00:03:13 neutron star merger we just detected.
00:03:13 --> 00:03:15 Four space telescopes were involved in
00:03:15 --> 00:03:17 making this discovery. Chandra, Fermy,
00:03:18 --> 00:03:20 the Neil Geral swift observatory and
00:03:20 --> 00:03:22 Hubble. It took all of them working
00:03:22 --> 00:03:25 together to pinpoint the location and
00:03:25 --> 00:03:27 confirm what they were seeing. The paper
00:03:27 --> 00:03:28 has just been published in the
00:03:28 --> 00:03:31 astrophysical journal letters. Though
00:03:31 --> 00:03:33 the gold in your jewelry, it may have
00:03:33 --> 00:03:36 come from a tiny galaxy in a gas stream
00:03:36 --> 00:03:38 after a chain of collisions spanning
00:03:38 --> 00:03:41 billions of years. I think that's one of
00:03:41 --> 00:03:43 the most extraordinary facts in all of
00:03:44 --> 00:03:44 science.
00:03:44 --> 00:03:47 >> Puts a new spin on where did this come
00:03:47 --> 00:03:49 from, doesn't it? Okay, coming up next,
00:03:49 --> 00:03:52 an update on Artemis 2. The mission that
00:03:52 --> 00:03:56 is almost almost ready to fly. So,
00:03:56 --> 00:03:59 Artemis 2, if you've been following the
00:03:59 --> 00:04:01 show, you know this mission has had
00:04:01 --> 00:04:02 quite a journey just to get to the
00:04:02 --> 00:04:04 launchpad. And today, there's a
00:04:04 --> 00:04:06 significant development.
00:04:06 --> 00:04:09 >> NASA has announced it will hold a flight
00:04:09 --> 00:04:11 readiness press conference tomorrow,
00:04:11 --> 00:04:13 Thursday, March 12th, at Kennedy Space
00:04:13 --> 00:04:15 Center in Florida. This is the formal
00:04:15 --> 00:04:17 milestone where engineers and mission
00:04:17 --> 00:04:19 leaders assess whether everything is
00:04:19 --> 00:04:22 technically ready to fly. It's a big
00:04:22 --> 00:04:24 deal. Just to bring everyone up to
00:04:24 --> 00:04:26 speed, Artemis 2 is the first crude
00:04:26 --> 00:04:29 mission of NASA's space launch system.
00:04:29 --> 00:04:32 Four astronauts, Reed Weisman, Victor
00:04:32 --> 00:04:34 Glover, Christina Coach, and Canadian
00:04:34 --> 00:04:37 Space Agency astronaut Jeremy Hansen,
00:04:37 --> 00:04:39 will fly around the moon and back on a
00:04:39 --> 00:04:41 10-day journey. It will be the first
00:04:41 --> 00:04:43 time humans have reached the moon's
00:04:43 --> 00:04:48 vicinity since Apollo 17 in 1972.
00:04:48 --> 00:04:50 >> The mission has had a series of delays.
00:04:50 --> 00:04:52 Back in February, a hydrogen leak was
00:04:52 --> 00:04:55 found during a wet dress rehearsal.
00:04:55 --> 00:04:57 Then, after a second successful
00:04:57 --> 00:04:59 rehearsal, a helium flow issue was
00:04:59 --> 00:05:01 discovered in the upper stage, which
00:05:01 --> 00:05:03 caused the rocket to be rolled back into
00:05:03 --> 00:05:04 the vehicle assembly building for
00:05:04 --> 00:05:07 repairs. That pushed the launch out of
00:05:07 --> 00:05:09 March entirely. The current target is
00:05:10 --> 00:05:12 April 1st at the earliest with roll out
00:05:12 --> 00:05:15 back to launch complex 39B expected
00:05:15 --> 00:05:18 around March 19th. BASA has also
00:05:18 --> 00:05:20 announced a major restructuring of the
00:05:20 --> 00:05:22 broader Artemis program, adding a new
00:05:22 --> 00:05:25 mission, increasing launch cadence, and
00:05:25 --> 00:05:27 targeting annual lunar missions with the
00:05:27 --> 00:05:30 first crude landing in 2028.
00:05:30 --> 00:05:32 >> So, tomorrow's press conference will be
00:05:32 --> 00:05:34 really telling. We'll know more about
00:05:34 --> 00:05:35 the state of the rocket, the official
00:05:36 --> 00:05:38 launch readiness verdict, and possibly
00:05:38 --> 00:05:39 more details on that April launch
00:05:39 --> 00:05:41 window. We'll of course have full
00:05:41 --> 00:05:43 coverage as the story develops.
00:05:43 --> 00:05:46 >> Fingers crossed for April. The crew has
00:05:46 --> 00:05:48 been in training for years. They deserve
00:05:48 --> 00:05:49 their moonshot.
00:05:49 --> 00:05:52 >> They absolutely do. Let's take a short
00:05:52 --> 00:05:54 break and come back with a story about a
00:05:54 --> 00:05:55 rocket trying very hard to leave the
00:05:55 --> 00:05:58 ground and a cosmic snowball fight
00:05:58 --> 00:06:00 nobody saw coming.
00:06:00 --> 00:06:03 >> All right, Firefly Aerospace. The small
00:06:03 --> 00:06:04 launch company has been trying to get
00:06:04 --> 00:06:07 its Alpha rocket back into the sky for
00:06:07 --> 00:06:09 weeks and once again the mission has
00:06:09 --> 00:06:11 been delayed. The mission is called
00:06:11 --> 00:06:13 Stairway to 7, which refers to this
00:06:13 --> 00:06:16 being Alpha's seventh flight overall. It
00:06:16 --> 00:06:18 was originally scheduled for March 1st,
00:06:18 --> 00:06:21 but high wind scrubbed that attempt.
00:06:21 --> 00:06:23 Then on March 9th, a sensor reading
00:06:23 --> 00:06:25 outside the expected range caused
00:06:25 --> 00:06:28 another standown. And last night, March
00:06:28 --> 00:06:30 10th, a third attempt was scrubbed
00:06:30 --> 00:06:32 during fluid loading after off-normal
00:06:32 --> 00:06:34 readings were detected.
00:06:34 --> 00:06:35 >> No new launch date has been announced
00:06:35 --> 00:06:38 yet. Firefly says they're reviewing the
00:06:38 --> 00:06:40 data and will confirm a new window once
00:06:40 --> 00:06:42 the investigation is complete.
00:06:42 --> 00:06:44 >> Now, it's worth understanding why this
00:06:44 --> 00:06:47 mission matters. Alpha has had a rough
00:06:47 --> 00:06:50 run. The sixth flight called message in
00:06:50 --> 00:06:52 a booster ended when the first stage
00:06:52 --> 00:06:54 broke apart just after separation,
00:06:54 --> 00:06:56 destroying the payload. Then in
00:06:56 --> 00:06:59 September, a booster intended for flight
00:06:59 --> 00:07:01 7 exploded during ground testing. The
00:07:01 --> 00:07:03 company has been working for nearly 10
00:07:03 --> 00:07:06 months to get back to the launchpad
00:07:06 --> 00:07:08 >> and stairway to 7 is carrying
00:07:08 --> 00:07:10 significant symbolic weight. It's the
00:07:10 --> 00:07:12 last flight of the alpha block one
00:07:12 --> 00:07:15 configuration. After this, Firefly moves
00:07:15 --> 00:07:18 to the upgraded block 2, which is 7 ft
00:07:18 --> 00:07:20 taller, uses new in-house avionics and
00:07:20 --> 00:07:23 batteries, improved thermal protection,
00:07:23 --> 00:07:25 and stronger carbon composite
00:07:25 --> 00:07:27 structures. Block two systems are
00:07:27 --> 00:07:29 actually flying on this mission in
00:07:29 --> 00:07:31 shadow mode, testing quietly in the
00:07:31 --> 00:07:33 background without controlling the
00:07:33 --> 00:07:36 flight. Firefly also had a big success
00:07:36 --> 00:07:38 recently. Their Blue Ghost lander
00:07:38 --> 00:07:40 completed the first ever private lunar
00:07:40 --> 00:07:42 surface mission last March. So, the
00:07:42 --> 00:07:44 company's in an interesting position,
00:07:44 --> 00:07:46 proven on the moon, but still working
00:07:46 --> 00:07:48 through reliability challenges with
00:07:48 --> 00:07:49 their launch vehicle.
00:07:49 --> 00:07:52 >> Small launch is hard. We're reading for
00:07:52 --> 00:07:54 them. When Stairway to 7 eventually gets
00:07:54 --> 00:07:56 off the ground, we'll give it the full
00:07:56 --> 00:07:58 coverage it deserves.
00:07:58 --> 00:08:01 >> Absolutely. Now, Cosmic Snowballs, you
00:08:01 --> 00:08:03 heard that, right?
00:08:03 --> 00:08:05 >> So, you might remember NASA's Dart
00:08:05 --> 00:08:08 mission, the spacecraft that
00:08:08 --> 00:08:10 intentionally smashed into an asteroid
00:08:10 --> 00:08:13 in 2022 to test whether we could deflect
00:08:13 --> 00:08:17 one that might threaten Earth. It worked
00:08:17 --> 00:08:19 beautifully, as we reported last week.
00:08:19 --> 00:08:22 But scientists are still finding new
00:08:22 --> 00:08:24 surprises in the data from that mission.
00:08:24 --> 00:08:27 And this one is genuinely delightful. A
00:08:27 --> 00:08:29 team at the University of Maryland has
00:08:29 --> 00:08:31 just published a study revealing that
00:08:31 --> 00:08:33 asteroids can throw slowmoving chunks of
00:08:33 --> 00:08:35 debris at each other in what they're
00:08:35 --> 00:08:38 calling, and I love this, a cosmic
00:08:38 --> 00:08:39 snowball fight.
00:08:40 --> 00:08:42 >> So, here's what happened. The Dart
00:08:42 --> 00:08:44 spacecraft hit an asteroid moon called
00:08:44 --> 00:08:47 Dimorphice, which orbits a larger
00:08:47 --> 00:08:50 asteroid called Ditimos. In the images
00:08:50 --> 00:08:52 captured by the spacecraft in the
00:08:52 --> 00:08:54 moments before impact, researchers
00:08:54 --> 00:08:58 noticed something odd. Faint fan-shaped
00:08:58 --> 00:09:01 streaks across Dorphice. Lead author
00:09:01 --> 00:09:03 Jessica Sunshine said, and this quote is
00:09:03 --> 00:09:06 great, "At first, we thought something
00:09:06 --> 00:09:08 was wrong with the camera, and then we
00:09:08 --> 00:09:09 thought it could have been something
00:09:09 --> 00:09:11 wrong with our image processing. But
00:09:12 --> 00:09:14 after months of painstaking work,
00:09:14 --> 00:09:16 stripping away boulder shadows and
00:09:16 --> 00:09:18 correcting for lighting, the streaks
00:09:18 --> 00:09:20 became clearer, not fainter. They were
00:09:20 --> 00:09:23 real. What the team discovered is that
00:09:23 --> 00:09:26 these streaks are the imprint of debris
00:09:26 --> 00:09:29 thrown off Ditimos by something called
00:09:29 --> 00:09:31 the Yorp effect, where sunlight
00:09:31 --> 00:09:34 gradually spins a small asteroid faster
00:09:34 --> 00:09:37 and faster until loose material flies
00:09:37 --> 00:09:40 off the surface. Some of that material
00:09:40 --> 00:09:43 then drifts across to Dorphice and lands
00:09:43 --> 00:09:45 on it, leaving these distinctive ray
00:09:45 --> 00:09:46 patterns.
00:09:46 --> 00:09:49 >> And the speed of this material transfer,
00:09:49 --> 00:09:52 just 30.7 cm/s.
00:09:52 --> 00:09:54 That's slower than a leisurely human
00:09:54 --> 00:09:57 walk. These are the gentlest cosmic
00:09:57 --> 00:10:00 snowballs imaginable. It's the first
00:10:00 --> 00:10:03 direct visual proof that material can
00:10:03 --> 00:10:05 travel naturally from one asteroid to
00:10:05 --> 00:10:08 another, and it has real implications
00:10:08 --> 00:10:11 for planetary defense. If binary
00:10:11 --> 00:10:13 asteroids are constantly exchanging
00:10:13 --> 00:10:16 material and reshaping each other,
00:10:16 --> 00:10:18 scientists need to account for that when
00:10:18 --> 00:10:20 modeling how to deflect one. There's
00:10:20 --> 00:10:23 also a follow-up mission on the way.
00:10:23 --> 00:10:26 ESA's Hera spacecraft is set to arrive
00:10:26 --> 00:10:28 at the Ditimos system in December this
00:10:28 --> 00:10:30 year and may be able to see whether
00:10:30 --> 00:10:32 those fan-shaped streaks survive the
00:10:32 --> 00:10:35 dart impact or whether new ones have
00:10:35 --> 00:10:38 formed. More cosmic forensics to come.
00:10:38 --> 00:10:40 >> A snowball fight spanning millions of
00:10:40 --> 00:10:43 years between two rocks in the dark of
00:10:43 --> 00:10:46 space. I love this job. After this
00:10:46 --> 00:10:48 break, Starship is getting even bigger
00:10:48 --> 00:10:50 and we go looking for the giant
00:10:50 --> 00:10:52 invisible sheet of matter that may be
00:10:52 --> 00:10:54 holding our cosmic neighborhood
00:10:54 --> 00:10:55 together.
00:10:55 --> 00:10:58 >> SpaceX's Starship program is marching on
00:10:58 --> 00:11:00 and the next milestone is approaching
00:11:00 --> 00:11:03 fast. Elon Musk announced this week that
00:11:03 --> 00:11:06 SpaceX is approximately 4 weeks away
00:11:06 --> 00:11:09 from launching Starship Flight 12, which
00:11:09 --> 00:11:11 will be the first flight of the upgraded
00:11:11 --> 00:11:14 Starship V3 configuration, the most
00:11:14 --> 00:11:16 powerful version of the vehicle yet.
00:11:16 --> 00:11:18 SpaceX engineers have been working
00:11:18 --> 00:11:21 through propellant system tests on ship
00:11:21 --> 00:11:24 39. That's the newest vehicle, and some
00:11:24 --> 00:11:27 of those tests produced some spectacular
00:11:27 --> 00:11:29 imagery this week. The team is moving
00:11:29 --> 00:11:31 methodically through pre-flight
00:11:31 --> 00:11:34 preparations at Starbase in Texas. Now,
00:11:34 --> 00:11:37 Starship V3 is described as a
00:11:37 --> 00:11:39 significant step up. The rocket already
00:11:39 --> 00:11:41 holds the title of the most powerful
00:11:41 --> 00:11:44 launch vehicle ever built, and the V3
00:11:44 --> 00:11:46 configuration pushes that capability
00:11:46 --> 00:11:48 further, which is critical for the
00:11:48 --> 00:11:50 missions ahead, including NASA's Aremis
00:11:50 --> 00:11:53 lunar landings, where a Starship variant
00:11:53 --> 00:11:55 will be used as the human landing
00:11:55 --> 00:11:58 system. Flight 12 won't carry the Aremis
00:11:58 --> 00:12:00 lander, of course, that's further down
00:12:00 --> 00:12:03 the road, but each integrated flight
00:12:03 --> 00:12:05 test builds toward that goal,
00:12:05 --> 00:12:08 demonstrating reliability, reusability,
00:12:08 --> 00:12:10 and the ability to handle increasingly
00:12:10 --> 00:12:12 complex mission profiles.
00:12:12 --> 00:12:14 >> So, if all goes to plan, we're looking
00:12:14 --> 00:12:17 at mid to late April for Flight 12
00:12:17 --> 00:12:19 liftoff. We'll keep a close eye on that
00:12:19 --> 00:12:21 timeline and give you the full launch
00:12:21 --> 00:12:23 preview when the date firms up. The pace
00:12:23 --> 00:12:25 of development at SpaceX is
00:12:25 --> 00:12:28 extraordinary. And now to cap off
00:12:28 --> 00:12:30 today's show, a cosmic mystery that's
00:12:30 --> 00:12:33 been puzzling astronomers for decades,
00:12:33 --> 00:12:35 and it might finally be solved.
00:12:35 --> 00:12:37 >> Here's a question that sounds simple. If
00:12:37 --> 00:12:40 our galaxy is so massive and has such a
00:12:40 --> 00:12:42 powerful gravitational pole, why are
00:12:42 --> 00:12:45 most nearby galaxies flying away from us
00:12:45 --> 00:12:47 rather than being pulled inward?
00:12:47 --> 00:12:49 >> It's something that's bugged astronomers
00:12:49 --> 00:12:52 for decades. Edwin Hubble established
00:12:52 --> 00:12:54 almost a century ago that the universe
00:12:54 --> 00:12:57 is expanding. Galaxies are receding from
00:12:57 --> 00:13:00 each other as space itself stretches.
00:13:00 --> 00:13:02 But the galaxies right next to us, just
00:13:02 --> 00:13:05 outside our local group, seem to be
00:13:05 --> 00:13:07 moving away faster than they should,
00:13:07 --> 00:13:09 even accounting for that expansion.
00:13:10 --> 00:13:11 Something wasn't adding up.
00:13:11 --> 00:13:13 >> A team from the University of Groigan in
00:13:13 --> 00:13:15 the Netherlands working with
00:13:15 --> 00:13:17 collaborators in Germany, France, and
00:13:17 --> 00:13:19 Sweden may have cracked it. They built
00:13:19 --> 00:13:21 what they call a virtual twin of our
00:13:21 --> 00:13:23 cosmic neighborhood, running advanced
00:13:23 --> 00:13:25 simulations starting from the early
00:13:25 --> 00:13:28 universe based on conditions measured in
00:13:28 --> 00:13:30 the cosmic microwave background all the
00:13:30 --> 00:13:33 way through to today. What they found is
00:13:33 --> 00:13:35 remarkable. The matter surrounding the
00:13:35 --> 00:13:37 local group, our cluster of galaxies,
00:13:38 --> 00:13:40 including the Milky Way and Andromeda,
00:13:40 --> 00:13:42 isn't spread out evenly in a sphere the
00:13:42 --> 00:13:45 way scientists had assumed. Instead,
00:13:45 --> 00:13:48 it's organized into a vast flat sheet of
00:13:48 --> 00:13:50 matter stretching tens of millions of
00:13:50 --> 00:13:53 light years across. Above and below this
00:13:53 --> 00:13:56 sheet lie enormous empty voids where
00:13:56 --> 00:13:58 there's essentially nothing. And when
00:13:58 --> 00:14:00 they included this flat structure in
00:14:00 --> 00:14:02 their models, the motion of 31 nearby
00:14:02 --> 00:14:04 galaxies matched almost perfectly with
00:14:04 --> 00:14:07 what astronomers actually observe. The
00:14:07 --> 00:14:09 sheets mass, which is mostly invisible
00:14:09 --> 00:14:12 dark matter, counterbalances the local
00:14:12 --> 00:14:14 group's gravitational pole. So galaxies
00:14:14 --> 00:14:16 within the plane drift outward in an
00:14:16 --> 00:14:19 orderly way while nothing falls in from
00:14:19 --> 00:14:21 the voids above and below.
00:14:21 --> 00:14:23 >> Bead researcher Ewad Wemp said this is
00:14:23 --> 00:14:26 the first detailed attempt to map the
00:14:26 --> 00:14:28 distribution and motion of dark matter
00:14:28 --> 00:14:31 in the region around the Milky Way and
00:14:31 --> 00:14:33 Andromeda. And co-ressearcher, Professor
00:14:33 --> 00:14:35 Amina Helme, who has worked on this
00:14:35 --> 00:14:38 problem for years, said she was thrilled
00:14:38 --> 00:14:40 to see that galaxy motions alone could
00:14:40 --> 00:14:43 reveal the mass distribution shaping our
00:14:43 --> 00:14:45 local cosmic neighborhood.
00:14:45 --> 00:14:46 >> What I find incredible about this is
00:14:46 --> 00:14:48 that we're essentially embedded in a
00:14:48 --> 00:14:51 cosmic structure we couldn't see. The
00:14:51 --> 00:14:53 Milky Way isn't floating freely in
00:14:53 --> 00:14:56 space. It's sitting on a vast flat sheet
00:14:56 --> 00:14:58 of dark matter surrounded by emptiness
00:14:58 --> 00:15:01 on either side in equilibrium. It's like
00:15:01 --> 00:15:03 being a grain of sand on a giant cosmic
00:15:04 --> 00:15:06 beach and only just realizing the beach
00:15:06 --> 00:15:09 exists. The paper is published in Nature
00:15:09 --> 00:15:12 Astronomy and we expect it to generate
00:15:12 --> 00:15:13 significant follow-up work as
00:15:13 --> 00:15:15 astronomers look to confirm the
00:15:15 --> 00:15:18 structure with additional observations.
00:15:18 --> 00:15:21 >> Amazing. What a lineup for episode 60.
00:15:21 --> 00:15:23 >> And that's our show for today. Let's do
00:15:23 --> 00:15:25 a quick recap of what we covered. NASA
00:15:25 --> 00:15:27 discovered a neutron star collision in a
00:15:27 --> 00:15:30 tiny galaxy buried in a gas stream. The
00:15:30 --> 00:15:32 first time this has been seen in such an
00:15:32 --> 00:15:34 unlikely location.
00:15:34 --> 00:15:37 >> The Aremis 2 flight readiness review is
00:15:37 --> 00:15:38 happening tomorrow. We're watching
00:15:38 --> 00:15:40 closely ahead of the April launch
00:15:40 --> 00:15:41 window.
00:15:41 --> 00:15:44 >> Firefly Alpha's Stairway to 7 mission is
00:15:44 --> 00:15:47 still on hold after a third scrub. A new
00:15:47 --> 00:15:48 launch date will be announced after
00:15:48 --> 00:15:51 engineering review. Dart mission data
00:15:51 --> 00:15:53 revealed the first ever direct visual
00:15:53 --> 00:15:56 proof of material transfer between two
00:15:56 --> 00:15:59 asteroids. The most gentle cosmic
00:15:59 --> 00:16:01 snowball fight you can imagine.
00:16:01 --> 00:16:03 >> SpaceX is about 4 weeks from launching
00:16:03 --> 00:16:06 Starship Flight 12, the first flight of
00:16:06 --> 00:16:09 the more powerful V3 configuration. and
00:16:09 --> 00:16:11 astronomers have discovered a vast flat
00:16:11 --> 00:16:14 sheet of dark matter surrounding our
00:16:14 --> 00:16:16 local group, finally explaining why
00:16:16 --> 00:16:19 nearby galaxies behave the way they do.
00:16:19 --> 00:16:21 >> As always, you can find us at
00:16:21 --> 00:16:22 astronomyaily.io
00:16:22 --> 00:16:25 and on all major podcast platforms, show
00:16:25 --> 00:16:27 notes, episode archive, and more are all
00:16:27 --> 00:16:28 there for you.
00:16:28 --> 00:16:30 >> If you're enjoying the show, please
00:16:30 --> 00:16:33 subscribe, leave us a review, and share
00:16:33 --> 00:16:35 us with a fellow space enthusiast. It
00:16:35 --> 00:16:38 means the world to us and genuinely
00:16:38 --> 00:16:39 helps the show grow.
00:16:39 --> 00:16:41 >> We'll be back tomorrow with more from
00:16:41 --> 00:16:43 the universe. Until then, keep looking
00:16:43 --> 00:16:44 up.
00:16:44 --> 00:16:56 >> Clear skies, everyone.
00:16:56 --> 00:17:00 Stories told.