Artemis 2 Delayed, SpaceX Unveils Stargaze Safety System

WEBVTT
Kind: captions
Language: en

00:00:00.400 --> 00:00:02.950
Welcome [music] to Astronomy Daily, your


00:00:02.960 --> 00:00:04.789
source for the latest space and


00:00:04.799 --> 00:00:06.950
astronomy news. I'm Anna. [music]


00:00:06.960 --> 00:00:08.870
>> And I'm Avery. We're here to bring you


00:00:08.880 --> 00:00:10.629
today's cosmic headlines on this


00:00:10.639 --> 00:00:13.669
Wednesday, February 4th, 2026.


00:00:13.679 --> 00:00:15.110
>> We've got a packed [music] show today


00:00:15.120 --> 00:00:17.349
with some significant developments.


00:00:17.359 --> 00:00:19.510
NASA's Aremis 2 mission [music] has hit


00:00:19.520 --> 00:00:21.269
another speed bump with their moon


00:00:21.279 --> 00:00:23.830
rocket experiencing some familiar issues


00:00:23.840 --> 00:00:26.150
during testing. SpaceX is making


00:00:26.160 --> 00:00:28.150
headlines [music] on two fronts today.


00:00:28.160 --> 00:00:30.390
Launching an innovative new space safety


00:00:30.400 --> 00:00:32.389
system while also dealing with a


00:00:32.399 --> 00:00:33.670
temporary [music] grounding of their


00:00:33.680 --> 00:00:36.630
Falcon 9 rocket. The James Web Space


00:00:36.640 --> 00:00:38.470
Telescope has spotted something [music]


00:00:38.480 --> 00:00:40.869
extraordinary in the early universe. A


00:00:40.879 --> 00:00:43.350
rare fiveway galaxy merger that's


00:00:43.360 --> 00:00:45.350
challenging our understanding of cosmic


00:00:45.360 --> 00:00:46.389
evolution.


00:00:46.399 --> 00:00:47.910
>> Scientists have finally cracked [music]


00:00:47.920 --> 00:00:50.389
a 50-year mystery about why nearby


00:00:50.399 --> 00:00:52.390
galaxies seem to be fleeing from us.


00:00:52.400 --> 00:00:54.630
[music] and it involves a massive cosmic


00:00:54.640 --> 00:00:55.430
void.


00:00:55.440 --> 00:00:57.630
>> And we'll wrap up with fascinating new


00:00:57.640 --> 00:00:59.910
[music] research on runaway stars.


00:00:59.920 --> 00:01:02.229
Massive stellar objects racing through


00:01:02.239 --> 00:01:04.789
the Milky Way at incredible speeds.


00:01:04.799 --> 00:01:05.990
>> Let's dive in.


00:01:06.000 --> 00:01:07.830
>> Our [music] top story today comes from


00:01:07.840 --> 00:01:10.230
NASA's Kennedy Space Center in Florida,


00:01:10.240 --> 00:01:12.469
where Artemis 2 mission has been delayed


00:01:12.479 --> 00:01:14.630
by at least a month following issues


00:01:14.640 --> 00:01:16.710
during a critical wet dress rehearsal


00:01:16.720 --> 00:01:17.590
test.


00:01:17.600 --> 00:01:19.350
>> This is the mission that will send four


00:01:19.360 --> 00:01:21.670
astronauts on a flyby of the moon. the


00:01:21.680 --> 00:01:23.910
first crude lunar mission in over 50


00:01:23.920 --> 00:01:26.630
years. The crew includes NASA astronauts


00:01:26.640 --> 00:01:29.350
Reed Weisman, Victor Glover, Christina


00:01:29.360 --> 00:01:31.190
and Canadian Space Agency


00:01:31.200 --> 00:01:33.190
astronaut Jeremy Hansen.


00:01:33.200 --> 00:01:35.990
>> So, what happened during this test? NASA


00:01:36.000 --> 00:01:38.630
concluded a 49-hour practice countdown


00:01:38.640 --> 00:01:41.910
on Tuesday after loading 700,000 gallons


00:01:41.920 --> 00:01:44.310
of liquid hydrogen and liquid oxygen


00:01:44.320 --> 00:01:46.469
into the massive space launch system


00:01:46.479 --> 00:01:48.630
rocket. And early in the tanking


00:01:48.640 --> 00:01:51.030
process, as we reported yesterday, they


00:01:51.040 --> 00:01:52.870
detected a hydrogen leak from the


00:01:52.880 --> 00:01:54.710
interface that routes cryogenic


00:01:54.720 --> 00:01:57.109
propellant into the rocket's core stage.


00:01:57.119 --> 00:01:58.230
Sound familiar?


00:01:58.240 --> 00:02:01.030
>> Unfortunately, yes. These hydrogen leaks


00:02:01.040 --> 00:02:02.630
are reminiscent of the issues that


00:02:02.640 --> 00:02:04.709
plagued the Aremis 1 launch attempts


00:02:04.719 --> 00:02:07.510
back in 2022. However, there's some good


00:02:07.520 --> 00:02:09.910
news. They did resolve the issue during


00:02:09.920 --> 00:02:11.990
this test and actually achieved full


00:02:12.000 --> 00:02:14.470
tanking on the first try, which NASA


00:02:14.480 --> 00:02:17.190
considers a tremendous success. That's


00:02:17.200 --> 00:02:19.589
actually quite significant progress. The


00:02:19.599 --> 00:02:21.270
resolution involved stopping the


00:02:21.280 --> 00:02:23.430
hydrogen flow, allowing the interface to


00:02:23.440 --> 00:02:25.910
warm up so the seals could recede, and


00:02:25.920 --> 00:02:28.150
then adjusting the flow of propellant.


00:02:28.160 --> 00:02:30.309
It worked, but it raised concerns about


00:02:30.319 --> 00:02:31.990
launch day operations.


00:02:32.000 --> 00:02:34.309
>> NASA administrator Jared Isaacman


00:02:34.319 --> 00:02:35.990
announced they're moving off the


00:02:36.000 --> 00:02:38.070
February launch window and targeting


00:02:38.080 --> 00:02:40.470
March for the earliest possible launch.


00:02:40.480 --> 00:02:42.390
The first opportunity next month is


00:02:42.400 --> 00:02:45.990
Friday, March 6th at 8:29 p.m. Eastern


00:02:46.000 --> 00:02:47.910
time with the window extending through


00:02:47.920 --> 00:02:50.630
March 11th. There were other issues,


00:02:50.640 --> 00:02:52.229
too, weren't there? I read about


00:02:52.239 --> 00:02:53.830
problems with a valve and some


00:02:53.840 --> 00:02:55.589
communication dropouts.


00:02:55.599 --> 00:02:58.070
>> Right. A valve associated with the Orion


00:02:58.080 --> 00:03:00.470
crew module hatch pressurization had to


00:03:00.480 --> 00:03:03.190
be retored, and closeout operations took


00:03:03.200 --> 00:03:05.110
longer than planned. Cold weather


00:03:05.120 --> 00:03:07.110
affected several cameras and other


00:03:07.120 --> 00:03:09.830
equipment. And perhaps most concerning,


00:03:09.840 --> 00:03:11.430
there were dropouts in audio


00:03:11.440 --> 00:03:13.030
communication channels that have been


00:03:13.040 --> 00:03:15.270
recurring over the past few weeks.


00:03:15.280 --> 00:03:17.509
>> What's the crew saying about all this?


00:03:17.519 --> 00:03:19.910
>> Commander Reed Wisman posted on social


00:03:19.920 --> 00:03:22.470
media expressing immense pride in seeing


00:03:22.480 --> 00:03:25.270
the rocket reach 100% fuel load,


00:03:25.280 --> 00:03:27.110
especially knowing how challenging the


00:03:27.120 --> 00:03:29.110
scenario was for the launch team. He


00:03:29.120 --> 00:03:30.869
said they're jumping back into training


00:03:30.879 --> 00:03:32.710
tomorrow to start preparations for


00:03:32.720 --> 00:03:33.509
March.


00:03:33.519 --> 00:03:35.509
>> And NASA's planning another wet dress


00:03:35.519 --> 00:03:37.110
rehearsal before the actual launch.


00:03:37.120 --> 00:03:37.830
Correct.


00:03:37.840 --> 00:03:39.830
>> That's right. Launch director Charlie


00:03:39.840 --> 00:03:41.830
Blackwell Thompson confirmed they'll


00:03:41.840 --> 00:03:43.750
conduct another wet dress before


00:03:43.760 --> 00:03:45.990
proceeding with the actual launch. The


00:03:46.000 --> 00:03:48.149
team needs to fully review all the data


00:03:48.159 --> 00:03:50.710
from this test, mitigate each issue, and


00:03:50.720 --> 00:03:52.550
return to testing before setting an


00:03:52.560 --> 00:03:54.390
official target launch date.


00:03:54.400 --> 00:03:56.789
>> It's a delay, but safety has to come


00:03:56.799 --> 00:03:58.550
first, especially with a crude mission


00:03:58.560 --> 00:04:01.509
to the moon. From the moon to low Earth


00:04:01.519 --> 00:04:04.470
orbit, SpaceX has just unveiled a


00:04:04.480 --> 00:04:06.869
revolutionary new space safety system


00:04:06.879 --> 00:04:09.589
called Stargaze that could fundamentally


00:04:09.599 --> 00:04:11.990
change how we manage the increasingly


00:04:12.000 --> 00:04:14.630
crowded space around our planet. This is


00:04:14.640 --> 00:04:17.189
fascinating technology, Anna. Stargaze


00:04:17.199 --> 00:04:19.590
is a space situational awareness system


00:04:19.600 --> 00:04:22.310
that uses data from nearly 30,000 star


00:04:22.320 --> 00:04:24.390
trackers across the Starlink satellite


00:04:24.400 --> 00:04:26.790
constellation to continuously monitor


00:04:26.800 --> 00:04:29.990
objects in low Earth orbit. 30,000 star


00:04:30.000 --> 00:04:32.629
trackers. That's an incredible network.


00:04:32.639 --> 00:04:35.110
And they're detecting approximately 30


00:04:35.120 --> 00:04:38.150
million transits daily across the fleet.


00:04:38.160 --> 00:04:40.310
That's a several order of magnitude


00:04:40.320 --> 00:04:42.390
increase in detection capability


00:04:42.400 --> 00:04:44.230
compared to conventional groundbased


00:04:44.240 --> 00:04:45.110
systems.


00:04:45.120 --> 00:04:46.950
>> The need for this kind of system has


00:04:46.960 --> 00:04:48.950
never been more urgent. Practices like


00:04:48.960 --> 00:04:51.830
leaving rocket bodies in LEO, operators


00:04:51.840 --> 00:04:53.510
maneuvering satellites without sharing


00:04:53.520 --> 00:04:55.110
trajectory predictions, and


00:04:55.120 --> 00:04:57.430
anti-satellite tests have all heightened


00:04:57.440 --> 00:04:59.670
collision risks. Conventional methods


00:04:59.680 --> 00:05:01.670
typically observe objects only a limited


00:05:01.680 --> 00:05:03.670
number of times per day, causing large


00:05:03.680 --> 00:05:05.909
uncertainties in orbital predictions.


00:05:05.919 --> 00:05:08.070
What makes Stargaze particularly


00:05:08.080 --> 00:05:10.230
powerful is that it provides conjunction


00:05:10.240 --> 00:05:12.390
screening results within minutes


00:05:12.400 --> 00:05:13.909
compared to the current industry


00:05:13.919 --> 00:05:16.790
standard of several hours. That speed


00:05:16.800 --> 00:05:18.469
can be the difference between a


00:05:18.479 --> 00:05:20.870
successful collision avoidance maneuver


00:05:20.880 --> 00:05:23.510
and a catastrophic impact.


00:05:23.520 --> 00:05:25.510
>> Basics actually shared a realworld


00:05:25.520 --> 00:05:27.270
example that demonstrates just how


00:05:27.280 --> 00:05:30.629
critical the system is. In late 2025, a


00:05:30.639 --> 00:05:32.469
Starlink satellite encountered a


00:05:32.479 --> 00:05:34.469
conjunction with a third party satellite


00:05:34.479 --> 00:05:36.629
that was performing maneuvers but whose


00:05:36.639 --> 00:05:39.110
operator wasn't sharing ephemeris data.


00:05:39.120 --> 00:05:41.350
>> Emerous data, that's the trajectory


00:05:41.360 --> 00:05:43.189
prediction information, right?


00:05:43.199 --> 00:05:45.350
>> Exactly. So, initially the close


00:05:45.360 --> 00:05:47.270
approach was anticipated to be about


00:05:47.280 --> 00:05:49.990
9,000 m away, considered a safe missed


00:05:50.000 --> 00:05:51.749
distance with zero probability of


00:05:51.759 --> 00:05:54.629
collision. But then, just 5 hours before


00:05:54.639 --> 00:05:56.390
the conjunction, the third party


00:05:56.400 --> 00:05:58.230
satellite performed a maneuver that


00:05:58.240 --> 00:05:59.990
collapsed the anticipated missed


00:06:00.000 --> 00:06:02.710
distance to just 60 m.


00:06:02.720 --> 00:06:06.230
>> 60 m. That's terrifyingly close in space


00:06:06.240 --> 00:06:08.870
terms. Stargaze quickly detected this


00:06:08.880 --> 00:06:10.629
maneuver and published an updated


00:06:10.639 --> 00:06:12.629
trajectory to the screening platform,


00:06:12.639 --> 00:06:14.870
generating new conjunction data messages


00:06:14.880 --> 00:06:17.189
that were immediately distributed. The


00:06:17.199 --> 00:06:19.029
Starling satellite was able to react


00:06:19.039 --> 00:06:20.550
within an hour of detecting the


00:06:20.560 --> 00:06:22.710
maneuver, planning an avoidance maneuver


00:06:22.720 --> 00:06:24.790
to reduce collision risk back down to


00:06:24.800 --> 00:06:25.590
zero.


00:06:25.600 --> 00:06:27.830
>> And here's the really important part.


00:06:27.840 --> 00:06:30.230
SpaceX is making this data available to


00:06:30.240 --> 00:06:33.110
all satellite operators free of charge.


00:06:33.120 --> 00:06:34.950
Starting this spring, satellite


00:06:34.960 --> 00:06:36.629
operators who submit their own


00:06:36.639 --> 00:06:38.710
trajectory predictions to the platform


00:06:38.720 --> 00:06:40.950
will receive conjunction data messages


00:06:40.960 --> 00:06:42.790
against Stargaze data.


00:06:42.800 --> 00:06:44.629
>> It's been in closed beta with over a


00:06:44.639 --> 00:06:46.629
dozen participating satellite operators


00:06:46.639 --> 00:06:48.790
and the response has been positive.


00:06:48.800 --> 00:06:50.550
SpaceX is drawing a parallel to


00:06:50.560 --> 00:06:52.550
commercial aviation. There are hundreds


00:06:52.560 --> 00:06:54.710
of thousands of sites daily, but they


00:06:54.720 --> 00:06:56.629
avoid collisions because they broadcast


00:06:56.639 --> 00:06:58.550
their location and flight plans to other


00:06:58.560 --> 00:07:01.110
aircraft. SpaceX is calling on all


00:07:01.120 --> 00:07:03.430
spacecraft operators to follow the same


00:07:03.440 --> 00:07:05.589
minimal standard of sharing predicted


00:07:05.599 --> 00:07:07.990
trajectories. Starlink updates and


00:07:08.000 --> 00:07:10.150
shares their ephemeris publicly every


00:07:10.160 --> 00:07:11.670
hour as an example.


00:07:11.680 --> 00:07:12.950
>> This is the kind of collaborative


00:07:12.960 --> 00:07:14.870
approach we need as space becomes more


00:07:14.880 --> 00:07:16.629
congested. It's not just about


00:07:16.639 --> 00:07:18.309
protecting SpaceX's massive


00:07:18.319 --> 00:07:20.469
constellation. It's about creating a


00:07:20.479 --> 00:07:22.870
safer orbital environment for everyone.


00:07:22.880 --> 00:07:25.110
Speaking of SpaceX, the company has


00:07:25.120 --> 00:07:27.589
temporarily grounded its Falcon 9 rocket


00:07:27.599 --> 00:07:29.670
following an issue with the upper stage


00:07:29.680 --> 00:07:31.909
on a recent Starlink launch, and the


00:07:31.919 --> 00:07:33.990
timing couldn't be more critical.


00:07:34.000 --> 00:07:36.390
>> This happened on Monday, February 2nd. A


00:07:36.400 --> 00:07:39.029
Falcon 9 successfully delivered 25


00:07:39.039 --> 00:07:41.270
Starlink satellites to low Earth orbit


00:07:41.280 --> 00:07:43.510
as planned. But after deploying the


00:07:43.520 --> 00:07:45.510
payloads, the rocket's upper stage


00:07:45.520 --> 00:07:47.749
failed to perform its de-orbit burn.


00:07:47.759 --> 00:07:49.990
That de-orbit burn is designed to bring


00:07:50.000 --> 00:07:51.909
the spent upper stage down for


00:07:51.919 --> 00:07:53.589
controlled destruction in Earth's


00:07:53.599 --> 00:07:56.309
atmosphere. Without it, we have another


00:07:56.319 --> 00:07:59.029
piece of debris in orbit. Exactly the


00:07:59.039 --> 00:08:00.950
kind of problem that Stargaze is


00:08:00.960 --> 00:08:02.550
designed to help monitor.


00:08:02.560 --> 00:08:04.790
>> The good news is the upper stage did


00:08:04.800 --> 00:08:07.029
manage to pacivate itself by venting


00:08:07.039 --> 00:08:09.189
propellant which lowered its perigee to


00:08:09.199 --> 00:08:12.469
about 110 km. According to satellite


00:08:12.479 --> 00:08:15.110
tracker Jonathan McDow, it will re-enter


00:08:15.120 --> 00:08:17.830
quickly. But SpaceX has grounded the


00:08:17.840 --> 00:08:19.990
Falcon 9 fleet while teams review data


00:08:20.000 --> 00:08:21.830
to determine root cause and corrective


00:08:21.840 --> 00:08:23.909
actions. And here's where the timing


00:08:23.919 --> 00:08:26.469
gets tricky. The Crew 12 astronaut


00:08:26.479 --> 00:08:27.990
mission to the International Space


00:08:28.000 --> 00:08:29.830
Station is currently scheduled to launch


00:08:29.840 --> 00:08:33.110
on February 11th, just 8 days from now.


00:08:33.120 --> 00:08:35.190
>> Crew 12 is particularly important


00:08:35.200 --> 00:08:37.589
because it will restore the ISS to its


00:08:37.599 --> 00:08:40.230
normal complement of seven crew members.


00:08:40.240 --> 00:08:42.070
The station has been operating with a


00:08:42.080 --> 00:08:44.310
skeleton crew of just three astronauts


00:08:44.320 --> 00:08:47.350
since January 15th when the four crew 11


00:08:47.360 --> 00:08:49.829
astronauts departed in the first ever


00:08:49.839 --> 00:08:52.470
medical evacuation from the ISS.


00:08:52.480 --> 00:08:54.470
>> NASA associate administrator Amit


00:08:54.480 --> 00:08:56.710
Kashatria confirmed that NASA teams from


00:08:56.720 --> 00:08:58.630
the commercial crew program are embedded


00:08:58.640 --> 00:09:00.790
in the investigation alongside SpaceX


00:09:00.800 --> 00:09:03.110
and the FAA. He said they're pressing


00:09:03.120 --> 00:09:05.030
towards the crew 12 window, but the


00:09:05.040 --> 00:09:06.790
launch will be contingent on the return


00:09:06.800 --> 00:09:09.110
to flight rationale. It's worth noting


00:09:09.120 --> 00:09:11.110
that the Falcon 9 has an incredible


00:09:11.120 --> 00:09:13.350
safety record. Last year alone, it


00:09:13.360 --> 00:09:15.509
launched a record-breaking


00:09:15.519 --> 00:09:18.710
165 times with all missions successful.


00:09:18.720 --> 00:09:20.710
Just a single mission experienced a


00:09:20.720 --> 00:09:23.190
significant anomaly, a Starlink launch


00:09:23.200 --> 00:09:25.430
where a booster toppled after landing at


00:09:25.440 --> 00:09:28.230
sea. That March 3rd incident was traced


00:09:28.240 --> 00:09:30.150
to a fuel leak in one of the booster


00:09:30.160 --> 00:09:32.630
nine Merlin engines which led to a fire


00:09:32.640 --> 00:09:35.030
that weakened a landing leg. SpaceX


00:09:35.040 --> 00:09:36.870
halted launches for a week at that time


00:09:36.880 --> 00:09:39.030
as well. The question now is whether


00:09:39.040 --> 00:09:40.870
they can resolve this upper stage issue


00:09:40.880 --> 00:09:43.110
quickly enough to meet the February 11th


00:09:43.120 --> 00:09:45.829
crew 12 launch date. If not, those three


00:09:45.839 --> 00:09:47.829
astronauts on the ISS will have to wait


00:09:47.839 --> 00:09:50.389
a bit longer for reinforcements. From


00:09:50.399 --> 00:09:52.470
orbital mechanics to the deepest reaches


00:09:52.480 --> 00:09:54.949
of space, the James Web Space Telescope


00:09:54.959 --> 00:09:57.430
has spotted something extraordinary. A


00:09:57.440 --> 00:09:59.430
fiveway galaxy merger in the early


00:09:59.440 --> 00:10:01.110
universe that's challenging our


00:10:01.120 --> 00:10:03.350
understanding of cosmic evolution.


00:10:03.360 --> 00:10:05.829
>> This is remarkable, Anna. The system


00:10:05.839 --> 00:10:08.470
consists of five compact, actively star


00:10:08.480 --> 00:10:10.310
forming galaxies that were emerging when


00:10:10.320 --> 00:10:12.949
the universe was only about 800 million


00:10:12.959 --> 00:10:15.509
years old. That's just 6% of the


00:10:15.519 --> 00:10:18.310
universe's current age. And the level of


00:10:18.320 --> 00:10:19.990
complexity is what's really stunning


00:10:20.000 --> 00:10:22.230
astronomers. These five galaxies are


00:10:22.240 --> 00:10:24.470
packed into a remarkably small region of


00:10:24.480 --> 00:10:26.949
space. They're separated by only tens of


00:10:26.959 --> 00:10:28.949
thousands of lightyear. To put that in


00:10:28.959 --> 00:10:30.790
perspective, that's far closer together


00:10:30.800 --> 00:10:32.630
than most neighboring galaxies in the


00:10:32.640 --> 00:10:33.910
modern universe.


00:10:33.920 --> 00:10:34.710
>> Dr.


00:10:34.720 --> 00:10:37.509
Hu from Texas&M University, the study's


00:10:37.519 --> 00:10:39.509
lead author, explained that what makes


00:10:39.519 --> 00:10:41.269
this remarkable is that a merger


00:10:41.279 --> 00:10:43.110
involving such a large number of


00:10:43.120 --> 00:10:45.430
galaxies was not expected so early in


00:10:45.440 --> 00:10:47.750
the universe's history. At that time,


00:10:47.760 --> 00:10:49.269
galaxy mergers were thought to be


00:10:49.279 --> 00:10:51.509
simpler, usually involving only two to


00:10:51.519 --> 00:10:52.790
three galaxies.


00:10:52.800 --> 00:10:54.870
>> But it's not just the number of galaxies


00:10:54.880 --> 00:10:56.949
that's impressive. These five galaxies


00:10:56.959 --> 00:10:59.030
are producing stars at a combined rate


00:10:59.040 --> 00:11:02.470
of roughly 250 solar masses per year.


00:11:02.480 --> 00:11:04.310
That's far exceeding typical star


00:11:04.320 --> 00:11:06.069
formation rates for that era.


00:11:06.079 --> 00:11:07.990
>> And this rapid stellar production has


00:11:08.000 --> 00:11:09.829
already enriched the system with heavier


00:11:09.839 --> 00:11:12.389
elements like oxygen. Materials forged


00:11:12.399 --> 00:11:14.310
in stellar interiors and dispersed


00:11:14.320 --> 00:11:16.550
through galactic interactions. The


00:11:16.560 --> 00:11:18.069
presence of these elements indicates


00:11:18.079 --> 00:11:20.310
that multiple generations of stars had


00:11:20.320 --> 00:11:22.790
already lived and died. The really


00:11:22.800 --> 00:11:24.870
fascinating part is that gas containing


00:11:24.880 --> 00:11:27.590
oxygen and hydrogen extends beyond the


00:11:27.600 --> 00:11:29.990
galaxies themselves. This suggests that


00:11:30.000 --> 00:11:31.990
gravitational interactions are pushing


00:11:32.000 --> 00:11:34.470
enriched material into intergalactic


00:11:34.480 --> 00:11:36.790
space, showing how early mergers may


00:11:36.800 --> 00:11:38.949
have shaped not just galaxies, but the


00:11:38.959 --> 00:11:41.030
larger cosmic environment. This


00:11:41.040 --> 00:11:42.870
discovery really disrupts the standard


00:11:42.880 --> 00:11:45.110
model of galaxy assembly. That model


00:11:45.120 --> 00:11:47.509
proposes a gradual buildup where small


00:11:47.519 --> 00:11:50.069
galaxies merge over long periods to form


00:11:50.079 --> 00:11:52.870
larger systems. But this fiveway merger


00:11:52.880 --> 00:11:55.430
demonstrates that complex multi-galaxy


00:11:55.440 --> 00:11:57.509
interactions were already underway less


00:11:57.519 --> 00:12:00.069
than a billion years after the Big Bang.


00:12:00.079 --> 00:12:02.630
>> Professor Casey Papovich, a co-author on


00:12:02.640 --> 00:12:05.590
the study, emphasized the implications


00:12:05.600 --> 00:12:08.389
by showing that a complex merger-driven


00:12:08.399 --> 00:12:11.509
system exists so early. It tells us our


00:12:11.519 --> 00:12:14.150
theories of how galaxies assemble and


00:12:14.160 --> 00:12:16.470
how quickly they do so need to be


00:12:16.480 --> 00:12:19.269
updated to match reality. This adds to


00:12:19.279 --> 00:12:22.150
the growing body of evidence from JWST


00:12:22.160 --> 00:12:24.470
that the early universe was capable of


00:12:24.480 --> 00:12:27.350
producing massive maturelook galaxies at


00:12:27.360 --> 00:12:29.910
astonishing speed. Matter in the early


00:12:29.920 --> 00:12:31.829
universe appears to have clustered more


00:12:31.839 --> 00:12:33.509
rapidly and efficiently than our


00:12:33.519 --> 00:12:35.190
simulation suggested.


00:12:35.200 --> 00:12:37.110
>> The study was published in Nature


00:12:37.120 --> 00:12:39.829
Astronomy and it's another example of


00:12:39.839 --> 00:12:43.430
how JWST is fundamentally changing our


00:12:43.440 --> 00:12:45.829
understanding of the cosmos.


00:12:45.839 --> 00:12:48.069
with cosmic mysteries, scientists have


00:12:48.079 --> 00:12:50.310
finally solved a 50-year-old puzzle


00:12:50.320 --> 00:12:52.629
about why nearby galaxies appear to be


00:12:52.639 --> 00:12:55.030
fleeing from our own Milky Way. And the


00:12:55.040 --> 00:12:57.430
answer involves a massive cosmic void


00:12:57.440 --> 00:12:59.110
right in our neighborhood.


00:12:59.120 --> 00:13:00.870
>> This is one of those mysteries that's


00:13:00.880 --> 00:13:03.110
been nagging at astronomers for decades,


00:13:03.120 --> 00:13:05.910
Avery. Most large galaxies near the


00:13:05.920 --> 00:13:07.910
Milky Way, with the exception of


00:13:07.920 --> 00:13:10.790
Andromeda, appear to be moving away from


00:13:10.800 --> 00:13:13.670
us and seem largely unaffected by the


00:13:13.680 --> 00:13:16.230
gravitational pole of our local group of


00:13:16.240 --> 00:13:17.430
galaxies.


00:13:17.440 --> 00:13:19.590
>> The local group being the Milky Way,


00:13:19.600 --> 00:13:21.590
Andromeda, and dozens of smaller


00:13:21.600 --> 00:13:24.629
galaxies. So, what's the solution? Led


00:13:24.639 --> 00:13:27.509
by Ewood at the Capta Institute in


00:13:27.519 --> 00:13:30.150
Granagan, an international research team


00:13:30.160 --> 00:13:32.790
used advanced computer simulations and


00:13:32.800 --> 00:13:35.110
discovered that matter just beyond the


00:13:35.120 --> 00:13:38.710
local group forms a broad flat structure


00:13:38.720 --> 00:13:40.949
stretching tens of millions of light


00:13:40.959 --> 00:13:44.069
years across. And here's the key. Vast


00:13:44.079 --> 00:13:46.949
empty regions lie above and below this


00:13:46.959 --> 00:13:47.990
structure.


00:13:48.000 --> 00:13:50.230
>> So we're basically living on a cosmic


00:13:50.240 --> 00:13:53.110
pancake surrounded by voids. That's


00:13:53.120 --> 00:13:55.509
actually a pretty good analogy. This


00:13:55.519 --> 00:13:58.069
flat distribution of matter is the only


00:13:58.079 --> 00:14:00.629
way to accurately account for both the


00:14:00.639 --> 00:14:02.710
combined mass of the Milky Way and


00:14:02.720 --> 00:14:05.590
Andromeda and the unexpected motions of


00:14:05.600 --> 00:14:07.430
nearby galaxies.


00:14:07.440 --> 00:14:09.829
>> But how does this flat structure explain


00:14:09.839 --> 00:14:12.310
why galaxies are moving away from us?


00:14:12.320 --> 00:14:15.430
>> It comes down to the local void, a vast


00:14:15.440 --> 00:14:18.870
empty region discovered back in 1987 by


00:14:18.880 --> 00:14:21.430
Brent Tully and Rick Fiser. The local


00:14:21.440 --> 00:14:25.189
void extends approximately 60 mega parex


00:14:25.199 --> 00:14:28.230
or about 200 million lightyear beginning


00:14:28.240 --> 00:14:30.710
at the edge of the local group. The


00:14:30.720 --> 00:14:32.629
local void is growing because there's


00:14:32.639 --> 00:14:34.710
very little matter inside it to exert


00:14:34.720 --> 00:14:37.350
gravitational pole. Our Milky Way sits


00:14:37.360 --> 00:14:39.750
in what's called the local sheet, a flat


00:14:39.760 --> 00:14:42.389
array of galaxies that bounds the void.


00:14:42.399 --> 00:14:44.470
And this local sheet is rushing away


00:14:44.480 --> 00:14:48.870
from the void center at 260 km/s.


00:14:48.880 --> 00:14:50.790
How fast is that affecting the Milky


00:14:50.800 --> 00:14:51.670
Way?


00:14:51.680 --> 00:14:53.829
>> The Milky Way's velocity away from the


00:14:53.839 --> 00:14:56.790
local void is 970,000


00:14:56.800 --> 00:15:01.189
km hour. That's 600,000 mph. It's


00:15:01.199 --> 00:15:03.110
astonishingly fast.


00:15:03.120 --> 00:15:05.590
>> So, the new simulations show that this


00:15:05.600 --> 00:15:08.470
hidden geometry, the flat plane of dark


00:15:08.480 --> 00:15:10.870
matter beyond the local group with voids


00:15:10.880 --> 00:15:13.670
above and below, is what's driving these


00:15:13.680 --> 00:15:15.509
galactic motions.


00:15:15.519 --> 00:15:17.829
>> Exactly. When researchers included this


00:15:17.839 --> 00:15:20.230
configuration in their simulations, they


00:15:20.240 --> 00:15:22.389
closely match the observed positions and


00:15:22.399 --> 00:15:25.030
speeds of nearby galaxies. It provides a


00:15:25.040 --> 00:15:27.189
coherent explanation for motions that


00:15:27.199 --> 00:15:29.110
have puzzled astronomers for half a


00:15:29.120 --> 00:15:30.150
century.


00:15:30.160 --> 00:15:32.069
>> This is connected to research about the


00:15:32.079 --> 00:15:34.310
Hubble tension, too, isn't it? The


00:15:34.320 --> 00:15:36.069
discrepancy in measurements of the


00:15:36.079 --> 00:15:38.230
universe's expansion rate.


00:15:38.240 --> 00:15:39.910
>> That's right. Some researchers have


00:15:39.920 --> 00:15:41.910
proposed that if we're inside a large


00:15:41.920 --> 00:15:44.150
local void, it could affect how we


00:15:44.160 --> 00:15:46.550
measure cosmic expansion, making the


00:15:46.560 --> 00:15:48.550
local universe appear to be expanding


00:15:48.560 --> 00:15:51.189
faster than it actually is. Though that


00:15:51.199 --> 00:15:53.350
particular idea remains controversial


00:15:53.360 --> 00:15:55.350
and needs more evidence. What's


00:15:55.360 --> 00:15:57.350
remarkable is that we're learning our


00:15:57.360 --> 00:15:59.590
immediate cosmic neighborhood is far


00:15:59.600 --> 00:16:01.670
more structured and dynamic than we


00:16:01.680 --> 00:16:03.990
previously understood. We're not just


00:16:04.000 --> 00:16:06.870
floating in a uniform sea of galaxies.


00:16:06.880 --> 00:16:09.350
We're on a sheet of matter bordering a


00:16:09.360 --> 00:16:10.790
massive void.


00:16:10.800 --> 00:16:13.030
>> And that void is shaping our galaxy's


00:16:13.040 --> 00:16:14.710
journey through space in fundamental


00:16:14.720 --> 00:16:15.590
ways.


00:16:15.600 --> 00:16:17.829
>> For our final story today, we're turning


00:16:17.839 --> 00:16:20.150
to some of the fastest objects in our


00:16:20.160 --> 00:16:23.030
galaxy. Runaway stars that are racing


00:16:23.040 --> 00:16:25.030
through the Milky Way at incredible


00:16:25.040 --> 00:16:27.430
speeds. Researchers from institutes


00:16:27.440 --> 00:16:29.509
across Spain have just completed the


00:16:29.519 --> 00:16:31.829
most extensive observational study to


00:16:31.839 --> 00:16:33.990
date of these stellar speeders,


00:16:34.000 --> 00:16:37.590
analyzing 2140 type stars, the brightest


00:16:37.600 --> 00:16:39.590
and most massive class of stars in our


00:16:39.600 --> 00:16:40.389
galaxy.


00:16:40.399 --> 00:16:42.230
>> These aren't just fastmoving stars,


00:16:42.240 --> 00:16:44.710
Avery. We're talking about stars with


00:16:44.720 --> 00:16:49.110
velocities that often exceed 700 km/s.


00:16:49.120 --> 00:16:51.350
That's fast enough to escape the Milky


00:16:51.360 --> 00:16:54.629
Way's gravity entirely. The term runaway


00:16:54.639 --> 00:16:56.949
stars was first used back in the early


00:16:56.959 --> 00:17:00.310
1960s by Dutch astronomer Adrien Blau.


00:17:00.320 --> 00:17:02.710
He observed stars moving at unusually


00:17:02.720 --> 00:17:04.949
high speeds and proposed they originated


00:17:04.959 --> 00:17:07.590
in binary systems and were ejected when


00:17:07.600 --> 00:17:09.590
the companion star collapsed and


00:17:09.600 --> 00:17:11.270
exploded in a supernova.


00:17:11.280 --> 00:17:14.309
>> By 2005, astronomers discovered even


00:17:14.319 --> 00:17:16.390
faster runaway stars, leading to the


00:17:16.400 --> 00:17:19.429
designation hypervelocity stars. These


00:17:19.439 --> 00:17:21.510
objects are fascinating because of the


00:17:21.520 --> 00:17:23.189
influence they have on galactic


00:17:23.199 --> 00:17:24.150
evolution.


00:17:24.160 --> 00:17:26.309
>> By escaping their systems of origin,


00:17:26.319 --> 00:17:28.549
these stars in radiate gas and dust in


00:17:28.559 --> 00:17:30.789
the interstellar medium, eventually


00:17:30.799 --> 00:17:32.630
seating it with heavy elements after


00:17:32.640 --> 00:17:35.029
they go supernova. This affects how


00:17:35.039 --> 00:17:37.350
future stars and planets will form.


00:17:37.360 --> 00:17:39.830
>> So, what did this new study reveal? The


00:17:39.840 --> 00:17:42.470
team used data from ESA's Gaia


00:17:42.480 --> 00:17:45.909
Observatory and the IAOB spectroscopic


00:17:45.919 --> 00:17:49.350
database to analyze these 2140 type


00:17:49.360 --> 00:17:51.510
stars. They found that most runaway


00:17:51.520 --> 00:17:54.070
stars rotate slowly while those that


00:17:54.080 --> 00:17:56.070
rotate faster are more likely to be


00:17:56.080 --> 00:17:57.990
linked to supernova explosions and


00:17:58.000 --> 00:18:00.070
binary systems. And here's an


00:18:00.080 --> 00:18:01.750
interesting finding. The highest


00:18:01.760 --> 00:18:03.830
velocity stars tend to be single,


00:18:03.840 --> 00:18:05.830
suggesting they were ejected from young


00:18:05.840 --> 00:18:07.350
clusters through gravitational


00:18:07.360 --> 00:18:10.150
interactions. So there are actually two


00:18:10.160 --> 00:18:11.990
different mechanisms creating runaway


00:18:12.000 --> 00:18:12.950
stars.


00:18:12.960 --> 00:18:15.750
>> Exactly. Some are explosively ejected by


00:18:15.760 --> 00:18:18.549
supernova in binary systems while others


00:18:18.559 --> 00:18:20.789
are gravitationally ejected from close


00:18:20.799 --> 00:18:23.110
encounters with star clusters. The study


00:18:23.120 --> 00:18:25.190
helps clarify the relative contributions


00:18:25.200 --> 00:18:28.150
of these two mechanisms. Lead author Mar


00:18:28.160 --> 00:18:30.630
Caretero Castrio, now at the European


00:18:30.640 --> 00:18:32.789
Southern Observatory, called this the


00:18:32.799 --> 00:18:34.870
most comprehensive observational study


00:18:34.880 --> 00:18:36.950
of its kind in the Milky Way. By


00:18:36.960 --> 00:18:38.950
combining information on rotation and


00:18:38.960 --> 00:18:40.630
binarity, they're providing


00:18:40.640 --> 00:18:42.549
unprecedented constraints on how these


00:18:42.559 --> 00:18:45.510
runaway stars are formed. The team also


00:18:45.520 --> 00:18:48.310
identified 12 runaway binary systems,


00:18:48.320 --> 00:18:50.630
including three X-ray binary sources


00:18:50.640 --> 00:18:52.710
that contain neutron stars or black


00:18:52.720 --> 00:18:54.950
holes and three additional systems that


00:18:54.960 --> 00:18:56.870
are likely candidates for hosting black


00:18:56.880 --> 00:18:59.110
holes. Perhaps the strongest evidence


00:18:59.120 --> 00:19:01.510
for multiple ejection mechanisms was


00:19:01.520 --> 00:19:04.230
this. Virtually no stars in the study


00:19:04.240 --> 00:19:06.950
exhibited both high velocities and rapid


00:19:06.960 --> 00:19:09.590
rotation. If all runaway stars came from


00:19:09.600 --> 00:19:11.669
the same process, you'd expect to see


00:19:11.679 --> 00:19:14.070
some with both characteristics. Future


00:19:14.080 --> 00:19:16.150
Gaia data releases and ongoing


00:19:16.160 --> 00:19:17.909
spectroscopic studies will help


00:19:17.919 --> 00:19:20.070
astronomers trace these stars back to


00:19:20.080 --> 00:19:22.310
their birthplaces within the Milky Way,


00:19:22.320 --> 00:19:24.470
which will confirm which mechanism was


00:19:24.480 --> 00:19:26.549
responsible in each case. And there


00:19:26.559 --> 00:19:28.390
might be another fascinating angle to


00:19:28.400 --> 00:19:30.310
this research. Understanding these


00:19:30.320 --> 00:19:32.470
systems could shed light on another role


00:19:32.480 --> 00:19:34.630
they may play in galactic evolution,


00:19:34.640 --> 00:19:36.310
potentially distributing the basic


00:19:36.320 --> 00:19:38.070
ingredients of life throughout the Milky


00:19:38.080 --> 00:19:40.710
Way as they travel. Cosmic messengers


00:19:40.720 --> 00:19:42.789
carrying the seeds of life across the


00:19:42.799 --> 00:19:44.870
galaxy. That's a beautiful thought to


00:19:44.880 --> 00:19:45.590
end on.


00:19:45.600 --> 00:19:47.350
>> And that wraps up today's episode of


00:19:47.360 --> 00:19:48.549
Astronomy Daily.


00:19:48.559 --> 00:19:50.710
>> From NASA's moon mission delays to


00:19:50.720 --> 00:19:53.510
SpaceX's new safety innovations, from


00:19:53.520 --> 00:19:55.830
ancient galaxy mergers to mysteries in


00:19:55.840 --> 00:19:57.990
our cosmic neighborhood, it's been quite


00:19:58.000 --> 00:19:59.909
a journey through the cosmos today.


00:19:59.919 --> 00:20:01.830
>> Thanks for joining us. For more space


00:20:01.840 --> 00:20:03.350
news, visit our website at


00:20:03.360 --> 00:20:05.750
astronomydaily.io, io where you can


00:20:05.760 --> 00:20:07.430
explore our full archive and stay


00:20:07.440 --> 00:20:08.950
updated on the latest cosmic


00:20:08.960 --> 00:20:09.909
discoveries.


00:20:09.919 --> 00:20:11.990
>> You can also find us on social media at


00:20:12.000 --> 00:20:14.390
Astro Daily Pod across all major


00:20:14.400 --> 00:20:16.630
platforms. Until next time, keep looking


00:20:16.640 --> 00:20:28.230
up. [music]


00:20:28.240 --> 00:20:36.644
Stories [music] told.


00:20:36.654 --> 00:20:38.674
[music and singing]