March 21, 2025

Oxygen in Distant Galaxies and Supernovae's Role in Extinction Events: S04E69

Astronomy Daily | Space News: S04E69
In this illuminating episode of Astronomy Daily, host Anna guides you through a series of remarkable discoveries that expand our understanding of the universe. From the detection of oxygen in the most distant...

Show Notes
Transcript

Astronomy Daily | Space News: S04E69
In this illuminating episode of Astronomy Daily, host Anna guides you through a series of remarkable discoveries that expand our understanding of the universe. From the detection of oxygen in the most distant galaxy to revolutionary advancements in telescope technology, this episode is a treasure trove of cosmic insights that will leave you in awe.
Highlights:
- Oxygen in the Distant Galaxy: Dive into the groundbreaking discovery of oxygen in galaxy Jades GSZ14.0, the farthest galaxy ever observed, which reveals unexpected maturity in the early universe. This finding challenges existing models of galaxy formation and evolution, showcasing the remarkable capabilities of the James Webb Space Telescope and ALMA.
- Supernovae and Mass Extinctions: Explore the intriguing theory that supernova explosions may have contributed to mass extinction events on Earth. New research suggests that nearby supernovae could have stripped our atmosphere of its ozone layer, exposing life to harmful radiation and leading to catastrophic consequences.
- Revolutionary Telescope Technology: Uncover the innovative new flat lens designed by engineers at the University of Utah, which could revolutionize astronomical observations. This lightweight lens promises to replace traditional bulky optics, making advanced imaging more accessible and practical for both professional and amateur astronomers.
- Extraordinary Nova Explosion: Learn about the recurrent nova LMCN1968.12A in the Large Magellanic Cloud, which shines nearly 100 times brighter than the sun during its eruptions. This nova's unique characteristics offer valuable insights into the behavior of cosmic explosions and their potential connections to supernovae.
- Venus's Inferior Conjunction: Get ready for Venus's upcoming inferior conjunction, where it will pass between Earth and the Sun. While this event may not provide dramatic visuals, it offers a valuable opportunity for astronomers to refine their understanding of celestial mechanics and planetary movements.
- Theoretical Dyson Swarms: Delve into the ambitious concept of Dyson swarms, hypothetical megastructures that advanced civilizations might build around stars. This study highlights the delicate balance between technological advancement and environmental preservation, raising important questions about our future energy needs.
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 signing off. Until next time, keep looking up and stay curious about the wonders of our universe.
00:00 - Welcome to Astronomy Daily
01:05 - Discovery of oxygen in distant galaxy
10:30 - Supernovae and mass extinction theory
17:00 - Revolutionary telescope lens technology
22:15 - Extraordinary nova explosion insights
27:30 - Venus's inferior conjunction
32:00 - Theoretical Dyson swarms and energy needs
✍️ Episode References
Oxygen in Distant Galaxy
[NASA](https://www.nasa.gov)
Supernovae and Extinction Events
[Research Study](https://www.example.com)
Revolutionary Telescope Technology
[University of Utah](https://www.utah.edu)
LMCN1968.12A Observations
[Astronomy Journal](

WEBVTT

1
00:00:00.160 --> 00:00:03.759
Hello, and welcome to Astronomy Daily. I'm anna your cosmic

2
00:00:03.759 --> 00:00:06.519
companion as we explore the wonders of the universe together.

3
00:00:07.200 --> 00:00:10.240
Today's episode is packed with discoveries that remind us just

4
00:00:10.279 --> 00:00:14.240
how vast and mysterious our cosmos really is. From oxygen

5
00:00:14.279 --> 00:00:17.079
found in the most distant galaxy ever observed, to evidence

6
00:00:17.120 --> 00:00:20.679
suggesting supernovae may have triggered mass extinctions right here on Earth.

7
00:00:21.239 --> 00:00:25.320
We're covering the full spectrum of astronomical fascination, and that's

8
00:00:25.399 --> 00:00:29.719
just the beginning. We'll also explore revolutionary new telescope technology

9
00:00:30.160 --> 00:00:33.119
that could transform how we see the stars, examine an

10
00:00:33.119 --> 00:00:36.759
extraordinary nova explosion that outshines our Sun one hundred times over,

11
00:00:37.320 --> 00:00:40.920
and discuss Venus's current celestial positioning as it passes between

12
00:00:40.960 --> 00:00:44.520
Earth and our star. Plus, we'll delve into the theoretical

13
00:00:44.560 --> 00:00:47.240
realm with a fascinating new study on dice and swarms,

14
00:00:47.719 --> 00:00:52.079
those hypothetical megastructures that advanced civilizations might build around their stars,

15
00:00:52.560 --> 00:00:55.719
and the startling impact they could have on planetary environments.

16
00:00:56.520 --> 00:00:59.960
The universe continues to surprise us at every turn, challenging

17
00:01:00.240 --> 00:01:04.599
understanding and expanding our cosmic perspective. Whether you're a seasoned

18
00:01:04.640 --> 00:01:08.000
stargazer or just curious about what lies beyond our atmosphere,

19
00:01:08.599 --> 00:01:11.200
I promise you'll find something to marvel at in today's

20
00:01:11.280 --> 00:01:14.879
roundup of astronomical news. So get comfortable as we embark

21
00:01:14.920 --> 00:01:18.400
on this twenty five minute journey through the cosmos, exploring

22
00:01:18.439 --> 00:01:22.239
the latest breakthroughs, discoveries, and theoretical frontiers that are shaping

23
00:01:22.239 --> 00:01:25.439
our understanding of space, from the earliest moments of our

24
00:01:25.519 --> 00:01:29.560
universe to the potential future of advanced civilizations. We're covering

25
00:01:29.599 --> 00:01:33.439
it all on today's episode of Astronomy Daily. In a

26
00:01:33.480 --> 00:01:36.200
discovery that's pushing the boundaries of what we thought we

27
00:01:36.280 --> 00:01:40.519
knew about the early universe, astronomers have detected oxygen in

28
00:01:40.560 --> 00:01:44.840
the most distant galaxy ever observed. This isn't just any finding.

29
00:01:45.319 --> 00:01:48.680
It's the farthest detection of oxygen ever made by humanity,

30
00:01:49.040 --> 00:01:52.400
giving us a glimpse into cosmic conditions when the universe

31
00:01:52.480 --> 00:01:56.400
was just a cosmic toddler. The galaxy in question, designated

32
00:01:56.439 --> 00:02:02.200
with the rather unwieldy name JADESGSZ fourteen zero, was spotted

33
00:02:02.239 --> 00:02:05.719
by the James Webb Space Telescope earlier this year. What

34
00:02:05.840 --> 00:02:09.039
makes this discovery so remarkable is that the light from

35
00:02:09.039 --> 00:02:12.400
this galaxy has taken about thirteen point four billion years

36
00:02:12.400 --> 00:02:15.840
to reach us. That's a journey spanning ninety eight percent

37
00:02:15.919 --> 00:02:19.039
of our universe's one three dot eight dash billion dash

38
00:02:19.120 --> 00:02:23.439
year lifetime. But here's where things get really interesting. This

39
00:02:23.560 --> 00:02:26.960
ancient galaxy contains about ten times the amount of heavy

40
00:02:27.039 --> 00:02:30.520
elements that scientists would expect to find in a galaxy

41
00:02:30.639 --> 00:02:33.719
existing just three hundred million years after the Big Bang.

42
00:02:34.560 --> 00:02:38.479
As researcher Sanderskoes from Leiden Observatory put it, it is

43
00:02:38.560 --> 00:02:41.639
like finding an adolescent where you would only expect babies.

44
00:02:42.120 --> 00:02:44.919
To understand why astronomers are so excited, we need to

45
00:02:44.960 --> 00:02:47.599
consider what the infant universe was supposed to look like.

46
00:02:48.080 --> 00:02:51.240
In those early cosmic days, the universe was primarily filled

47
00:02:51.280 --> 00:02:55.800
with hydrogen and helium, the lightest elements. Heavier elements, which

48
00:02:55.800 --> 00:03:01.560
astronomers somewhat confusingly call metals, were extremely rare. These heavier

49
00:03:01.599 --> 00:03:06.319
elements are forged inside stars and scattered through space when

50
00:03:06.360 --> 00:03:11.719
those stars die in supernova explosions. This process then enriches

51
00:03:11.800 --> 00:03:15.680
gas clouds that form the next generation of stars. It's

52
00:03:15.800 --> 00:03:20.479
essentially a cosmic recycling program that becomes more efficient over time,

53
00:03:21.000 --> 00:03:23.759
so finding a galaxy so metal rich this early in

54
00:03:23.840 --> 00:03:29.000
cosmic history suggests that Jade's gsz fourteen zero matured much

55
00:03:29.039 --> 00:03:33.120
faster than our models predicted. This discovery is forcing astronomers

56
00:03:33.159 --> 00:03:36.680
to reconsider their understanding of how quickly galaxies can form

57
00:03:36.759 --> 00:03:40.759
and evolve in the early universe. The chemical analysis of

58
00:03:40.800 --> 00:03:44.439
this distant galaxy was made possible through a collaboration between

59
00:03:44.479 --> 00:03:48.199
the James Web Space Telescope and the Atacama Large Millimeter

60
00:03:48.319 --> 00:03:53.120
Submillimeter Array, or ALMA for short. While Web discovered the galaxy,

61
00:03:53.479 --> 00:03:57.800
alma's measurements allowed astronomers to determine its chemical composition with

62
00:03:57.960 --> 00:04:03.639
astonishing precision. Stefanocarneani of the Scuola Normale Superiori in Italy

63
00:04:04.120 --> 00:04:08.120
expressed his astonishment at these unexpected results, noting that they

64
00:04:08.479 --> 00:04:11.560
opened a new view on the first phases of galaxy evolution.

65
00:04:12.639 --> 00:04:15.000
The evidence that a galaxy is already mature in what

66
00:04:15.039 --> 00:04:18.720
we considered the infant universe raises profound questions about when

67
00:04:18.759 --> 00:04:22.480
and how galaxies formed. Perhaps even more impressive is the

68
00:04:22.519 --> 00:04:28.040
precision of alma's measurements. According to researcher Eleonora Parlanti, ALMA

69
00:04:28.079 --> 00:04:32.040
provided an extraordinarily precise measurement of the galaxy's distance, down

70
00:04:32.079 --> 00:04:35.399
to an uncertainty of just zero point zero zero five percent.

71
00:04:36.639 --> 00:04:39.680
To put that in perspective, that's like measuring a distance

72
00:04:39.720 --> 00:04:42.920
of one kilometer with an accuracy of just five centimeters.

73
00:04:43.920 --> 00:04:48.079
This discovery highlights the incredible synergy between our newest space telescope,

74
00:04:48.480 --> 00:04:52.879
James Webb, and ground based observatories like ALMA. Together, they're

75
00:04:52.879 --> 00:04:55.879
giving us an unprecedented look at the earliest chapters of

76
00:04:55.879 --> 00:05:00.000
our universe's story, revealing that cosmic evolution may have proceeded

77
00:05:00.240 --> 00:05:04.680
much faster than we previously thought. As astronomer Richard Bowens noted,

78
00:05:05.000 --> 00:05:09.680
this finding showcases the amazing synergy between ALMA and JWST

79
00:05:10.120 --> 00:05:13.759
to reveal the formation and evolution of the first galaxies.

80
00:05:14.639 --> 00:05:17.519
It seems that with each new observation, we're rewriting the

81
00:05:17.560 --> 00:05:22.040
timeline of cosmic history. Next up today, did you know

82
00:05:22.120 --> 00:05:25.480
that the dinosaurs might have been wiped out by cosmic fireworks.

83
00:05:26.439 --> 00:05:29.079
While an asteroid impact has long been the leading theory

84
00:05:29.079 --> 00:05:33.720
for their extinction, new research suggests that explosive supernova deaths

85
00:05:33.720 --> 00:05:36.560
of nearby massive stars may have played a significant role

86
00:05:36.959 --> 00:05:39.680
in triggering at least two major extinction events in Earth's

87
00:05:39.680 --> 00:05:44.120
distant past. A team of astronomers has discovered that supernovae

88
00:05:44.160 --> 00:05:47.319
occurring within sixty light years of Earth could have had

89
00:05:47.480 --> 00:05:52.199
catastrophic consequences for life on our planet. These stellar explosions

90
00:05:52.319 --> 00:05:55.680
represent some of the most energetic phenomena in the universe,

91
00:05:56.120 --> 00:05:59.240
and their proximity to Earth could have stripped our planet's

92
00:05:59.279 --> 00:06:03.759
atmosphere of its protective ozone layer. Without this crucial defense,

93
00:06:04.240 --> 00:06:06.959
life on Earth would have been exposed to damaging ultraviolet

94
00:06:07.040 --> 00:06:10.319
radiation from the Sun. As study co author Nick Wright

95
00:06:10.319 --> 00:06:14.199
from Keele University put it, a slightly more distant supernova

96
00:06:14.560 --> 00:06:17.680
could still cause considerable loss of life, but at this

97
00:06:17.839 --> 00:06:22.360
distance it would be terrifying. Right In, his colleagues conducted

98
00:06:22.360 --> 00:06:25.600
what amounts to a virtual census of our cosmic neighborhood.

99
00:06:26.199 --> 00:06:29.680
Using data from the now retired Guaya satellite. They examined

100
00:06:29.720 --> 00:06:32.519
more than twenty four thousand of the most luminous stars

101
00:06:32.839 --> 00:06:35.839
within about three thousand, two hundred and sixty light years

102
00:06:35.879 --> 00:06:38.800
of the Sun. Their goal was to identify groups of

103
00:06:38.920 --> 00:06:42.800
young massive stars and reconstruct the history of star formation

104
00:06:42.959 --> 00:06:46.839
near our solar system. What's particularly striking is that when

105
00:06:46.879 --> 00:06:50.759
the team calculated the rate of nearby supernova, they found

106
00:06:50.800 --> 00:06:54.079
it matched up remarkably well with the timing of unexplained

107
00:06:54.160 --> 00:06:58.360
mass extinction events on Earth. Two events in particular stood out,

108
00:06:58.399 --> 00:07:01.879
the Late Devonian extinction of about three hundred seventy two million

109
00:07:01.959 --> 00:07:05.959
years ago, which wiped out seventy five percent of all species,

110
00:07:06.279 --> 00:07:10.360
particularly affecting fish in ancient seas and lakes, and the

111
00:07:10.480 --> 00:07:14.000
Ordovician extinction from four hundred forty five million years ago,

112
00:07:14.319 --> 00:07:18.319
which eliminated roughly eighty five percent of marine species. It

113
00:07:18.399 --> 00:07:21.040
surprised me that the two rates were so similar, which

114
00:07:21.040 --> 00:07:24.639
made us want to highlight it. Wright noted previous research

115
00:07:24.680 --> 00:07:28.160
has already found evidence supporting cosmic influence on Earth's history.

116
00:07:28.720 --> 00:07:33.040
Scientists have detected radioactive isotopes like iron sixty in Antarctic

117
00:07:33.120 --> 00:07:36.199
snow and on the Moon's surface, materials that could only

118
00:07:36.279 --> 00:07:40.040
have come from interstellar sources like supernova. These findings have

119
00:07:40.079 --> 00:07:43.519
been linked to the depletion of Earth's ozone layer caused

120
00:07:43.519 --> 00:07:46.639
by cosmic rays showered onto our planet when stars exploded.

121
00:07:47.160 --> 00:07:50.399
The new study simulations showed that approximately one to two

122
00:07:50.519 --> 00:07:54.160
supernova occur each century in galaxies like our Milky Way.

123
00:07:55.120 --> 00:07:58.160
More critically, within that dangerous sixty light year radius of Earth,

124
00:07:58.480 --> 00:08:00.519
the rate works out to about two to two point

125
00:08:00.600 --> 00:08:05.519
five supernova per billion years. This estimate aligns remarkably well

126
00:08:05.560 --> 00:08:08.639
with the number of unexplained mass extinction events on Earth,

127
00:08:09.160 --> 00:08:13.399
specifically the Devonian and Ordovician extinctions, both of which occurred

128
00:08:13.439 --> 00:08:16.680
within the last billion years. While the researchers are careful

129
00:08:16.720 --> 00:08:19.959
to note that they don't have definitive proof these extinctions

130
00:08:20.000 --> 00:08:23.160
were caused by supernova, the matching rates make it a

131
00:08:23.199 --> 00:08:27.120
compelling possibility. As Alexis Quintana, who led the study, put it,

132
00:08:27.720 --> 00:08:31.800
these findings are a great illustration for how massive stars

133
00:08:31.800 --> 00:08:35.879
can act as both creators and destructors of life. Supernova

134
00:08:35.919 --> 00:08:40.559
explosions distribute heavy chemical elements throughout space, essential building blocks

135
00:08:40.559 --> 00:08:43.399
for new stars and planets. But if a planet like

136
00:08:43.399 --> 00:08:46.279
Earth happens to be too close when these cosmic bombs detonate,

137
00:08:46.399 --> 00:08:50.200
the consequences can be devastating. So the next time you

138
00:08:50.200 --> 00:08:53.200
gaze up at the night sky, remember that those twinkling

139
00:08:53.200 --> 00:08:56.360
stars might hold both the secrets to life's beginnings and

140
00:08:56.440 --> 00:09:00.360
potentially the power to dramatically alter its course here on Earth.

141
00:09:01.879 --> 00:09:03.639
Next let's take a look at a subject we don't

142
00:09:03.679 --> 00:09:07.360
visit too often, but this id truly fascinating. In what

143
00:09:07.440 --> 00:09:12.000
could be a revolutionary breakthrough for astronomy, engineers and astronomers

144
00:09:12.000 --> 00:09:15.440
at the University of Utah have designed an innovative new

145
00:09:15.480 --> 00:09:18.159
type of telescope lens that might forever change how we

146
00:09:18.200 --> 00:09:22.399
observe the cosmos. Unlike traditional bulky lenses and mirrors, this

147
00:09:22.440 --> 00:09:26.440
new technology is remarkably thin, a flat lens with microscopic

148
00:09:26.480 --> 00:09:30.559
etchings that refract light in precisely controlled ways. The most

149
00:09:30.559 --> 00:09:35.080
striking feature of this lens is its incredible thinness. Measuring

150
00:09:35.159 --> 00:09:38.600
less than a millimeter thick, it's practically a wafer compared

151
00:09:38.600 --> 00:09:43.200
to conventional telescope optics. Yet despite its slim profile, the

152
00:09:43.279 --> 00:09:47.440
lens performs remarkably well in initial tests, suggesting it could

153
00:09:47.440 --> 00:09:53.080
eventually replace the heavier, bulkier components typically used in astronomical telescopes.

154
00:09:53.960 --> 00:09:57.840
Our computational techniques suggested we could design multi level, diffractive

155
00:09:57.879 --> 00:10:01.559
flat lenses with large apertures that could focus light across

156
00:10:01.559 --> 00:10:05.879
the visible spectrum, explained Rajesh Mennin, a professor of engineering

157
00:10:05.919 --> 00:10:09.360
at Utah who worked on the project. The technology behind

158
00:10:09.360 --> 00:10:12.519
this breakthrough is fascinating. The team used a technique called

159
00:10:12.559 --> 00:10:17.200
grayscale optical lithography, a variation of methods typically used for

160
00:10:17.240 --> 00:10:22.159
etching electronics onto silicon wafers, to create microscopic concentric rings

161
00:10:22.200 --> 00:10:25.919
on a glass substrate. Most of the half millimeter thickness

162
00:10:25.960 --> 00:10:29.399
is actually just the glass itself, while the ringed grooves

163
00:10:29.440 --> 00:10:32.600
that do all the optical work are incredibly shallow at

164
00:10:32.639 --> 00:10:36.159
just two point four microns deep. While the concept of

165
00:10:36.279 --> 00:10:40.080
using concentric rings in flat lenses isn't entirely new, this

166
00:10:40.200 --> 00:10:43.600
multi level difractive lens, or MDL solves one of the

167
00:10:43.600 --> 00:10:48.679
biggest challenges in optics, chromatic aberration. This problem occurs when

168
00:10:48.720 --> 00:10:52.480
different wavelengths of light focus at different points, causing color

169
00:10:52.519 --> 00:10:57.039
fringing around objects. The Utah team's design cleverly brings all

170
00:10:57.120 --> 00:11:01.320
wavelengths from four hundred to eight hundred nanom covering the

171
00:11:01.480 --> 00:11:05.240
entire visible spectrum and into near infrared, to focus at

172
00:11:05.240 --> 00:11:08.840
exactly the same point. The weight difference is dramatic. Their

173
00:11:08.879 --> 00:11:11.799
one hundred mm prototype lens, with a focal length of

174
00:11:11.799 --> 00:11:14.919
two hundred mmm, weighs just twenty five grams compared to

175
00:11:14.919 --> 00:11:17.600
the two hundred and eleven grams of a similarly sized

176
00:11:17.600 --> 00:11:21.480
commercial lens that's seventeen mm thick at its center. That's

177
00:11:21.519 --> 00:11:24.960
more than an eighty eight percent reduction in weight. To

178
00:11:25.039 --> 00:11:28.720
demonstrate its capabilities, the team tested the lens by imaging

179
00:11:28.759 --> 00:11:32.399
both the Sun and the Moon, successfully revealing sunspots and

180
00:11:32.519 --> 00:11:36.840
accurate geological features on the lunar surface. This real world

181
00:11:36.840 --> 00:11:42.240
performance validation suggests the technology is viable for practical astronomical applications.

182
00:11:42.679 --> 00:11:47.080
The implications for space telescopes could be particularly transformative. Consider

183
00:11:47.120 --> 00:11:50.080
that the Hubble Space telescopes two point four meter primary

184
00:11:50.080 --> 00:11:53.720
mirror weighs a whopping one eight hundred and twenty five pounds,

185
00:11:54.039 --> 00:11:57.360
while the James Web Space telescopes segmented twenty one foot

186
00:11:57.399 --> 00:12:01.159
mirror weighs one thousand, five hundred fifty five pound. The

187
00:12:01.200 --> 00:12:04.960
tremendous mass of these components significantly drives up launch costs

188
00:12:04.960 --> 00:12:10.080
and engineering complexity. On Earth, the largest individual telescope mirrors

189
00:12:10.080 --> 00:12:12.799
currently max out at around twenty six to thirty three

190
00:12:12.840 --> 00:12:16.559
feet before gravity causes them to sag under their own weight.

191
00:12:17.440 --> 00:12:21.240
A flat, lightweight alternative could potentially break through these limitations,

192
00:12:21.840 --> 00:12:25.240
enabling even larger light gathering surfaces, both in space and

193
00:12:25.279 --> 00:12:29.080
on the ground. Our demonstration is a stepping stone towards

194
00:12:29.120 --> 00:12:33.799
creating very large aperture, lightweight flat lenses with the capability

195
00:12:33.799 --> 00:12:36.840
of capturing full color images for use in air and

196
00:12:36.919 --> 00:12:40.840
space based telescopes, said Apridim Majumder, who led the team

197
00:12:40.840 --> 00:12:44.159
behind the prototype. While the current prototype is modest at

198
00:12:44.159 --> 00:12:48.120
four inches in diameter, the breakthrough proves the concept is viable.

199
00:12:48.559 --> 00:12:53.159
If successfully scaled up, these lenses could potentially transform not

200
00:12:53.240 --> 00:12:57.000
just professional observatories, but eventually make their way into amateur

201
00:12:57.039 --> 00:13:03.440
telescopes as well, making advanced astronomic imaging more accessible to everyone.

202
00:13:03.519 --> 00:13:07.559
In a stellar discovery that's illuminating our understanding of cosmic explosions,

203
00:13:07.879 --> 00:13:12.000
astronomers have conducted the first ever near infrared study of

204
00:13:12.039 --> 00:13:16.919
a recurrent nova beyond our Milky Way galaxy. This extraordinary nova,

205
00:13:17.240 --> 00:13:21.480
designated LMCN one thousand, nine hundred sixty eight twelve A

206
00:13:22.039 --> 00:13:26.399
or LMC sixty eight, resides in the large Magellanic Cloud

207
00:13:26.480 --> 00:13:31.200
and has been revealing some truly shocking characteristics. Nova explosions

208
00:13:31.200 --> 00:13:34.480
occur in binary star systems, where a white dwarf a

209
00:13:34.600 --> 00:13:36.960
dense stellar remnant about the size of Earth, but with

210
00:13:37.039 --> 00:13:40.080
a mass comparable to our Sun pulls material from its

211
00:13:40.080 --> 00:13:43.759
companion star. This stolen material accumulates on the white dwarf's

212
00:13:43.759 --> 00:13:47.679
surface until it triggers a thermonuclear explosion. While most novas

213
00:13:47.679 --> 00:13:50.879
have been observed erupting just once, LMC sixty eight belongs

214
00:13:50.919 --> 00:13:54.279
to the rare category of recurrent novas, with explosions occurring

215
00:13:54.279 --> 00:13:58.679
with remarkable regularity. Every four years, a hot white dwarf

216
00:13:58.720 --> 00:14:02.399
star siphons off material from its cool companion star, explained

217
00:14:02.440 --> 00:14:06.519
astronomer Nia Evans of Keele University. The material piles up

218
00:14:06.519 --> 00:14:09.080
on the white dwarf's surface and eventually detonates in a

219
00:14:09.080 --> 00:14:13.879
thermonuclear runaway. Once the explosion has subsided, the siphoning starts

220
00:14:13.919 --> 00:14:19.000
all over, and in time another thermonuclear explosion occurs. What

221
00:14:19.120 --> 00:14:22.440
makes LMC sixty eight particularly special is that it was

222
00:14:22.480 --> 00:14:26.440
the first recurrent nova ever observed outside our galaxy. First

223
00:14:26.480 --> 00:14:29.399
spotted in nineteen sixty eight and again in nineteen ninety,

224
00:14:29.879 --> 00:14:33.879
it has maintained its four year eruption cycle with clockwork precision.

225
00:14:34.519 --> 00:14:38.759
After its twenty twenty eruption, NASA's Neil Garrel's Swift Observatory

226
00:14:39.200 --> 00:14:43.399
had been closely monitoring it anticipating the next explosion, which

227
00:14:43.480 --> 00:14:47.480
arrived on schedule in August twenty twenty four. The latest

228
00:14:47.480 --> 00:14:52.200
observations have revealed something truly extraordinary. During its eruption phase,

229
00:14:52.600 --> 00:14:55.720
this nova shines at nearly one hundred times the brightness

230
00:14:55.720 --> 00:14:59.759
of our Sun, making it an exceptionally powerful cosmic event.

231
00:15:00.440 --> 00:15:05.200
By analyzing the nova's near infrared light, astronomers gained unprecedented

232
00:15:05.240 --> 00:15:09.720
insights into its ultra hot phase. Using spectroscopy to examine

233
00:15:09.759 --> 00:15:13.480
the different wavelengths of light, they identified chemical elements present

234
00:15:13.480 --> 00:15:17.480
in the explosion and discovered unexpectedly intense signals from silicon

235
00:15:17.519 --> 00:15:21.320
atoms that had been ionized nine times, a process requiring

236
00:15:21.480 --> 00:15:26.240
enormous energy. The ionized silicon shining at almost one hundred

237
00:15:26.320 --> 00:15:30.399
times brighter than the sun is unprecedented, noted Tom gabal

238
00:15:30.840 --> 00:15:34.759
no Ar, lab Emeritus astronomer. And while this signal is shocking,

239
00:15:35.080 --> 00:15:38.200
it's also shocking what's not there. We would have expected

240
00:15:38.200 --> 00:15:42.840
to also see signatures of highly energized sulfur, phosphorus, calcium,

241
00:15:42.840 --> 00:15:46.919
and aluminum. This absence of expected chemical signatures points to

242
00:15:46.960 --> 00:15:51.559
something unusual happening with LMC sixty eight. The astronomers believe

243
00:15:51.600 --> 00:15:55.519
the answer might lie in two factors, exceptionally high temperatures

244
00:15:55.840 --> 00:15:59.000
and the star's location in the metal deficient environment of

245
00:15:59.039 --> 00:16:03.200
the large Magellana Cloud. The coronal temperature of LMC sixty

246
00:16:03.200 --> 00:16:06.759
eight reaches a blistering five point four million degrees fahrenheit

247
00:16:07.120 --> 00:16:10.759
that's three million degrees celsius, far hotter than typical novas.

248
00:16:11.159 --> 00:16:15.720
At these extreme temperatures, atoms undergo collisional ionization, where fast

249
00:16:15.720 --> 00:16:19.240
moving electrons strip atoms of more electrons than usual, pushing

250
00:16:19.279 --> 00:16:24.240
them into higher energy states. Additionally, since the nova's companion

251
00:16:24.360 --> 00:16:29.080
star likely has lower metallicity fewer heavy elements typical of

252
00:16:29.120 --> 00:16:32.399
the large Magellanic Cloud, this could lead to more powerful

253
00:16:32.440 --> 00:16:35.759
explosions as more material is needed to trigger the eruption.

254
00:16:36.879 --> 00:16:41.000
What makes these recurrent novas particularly intriguing is their potential

255
00:16:41.000 --> 00:16:45.960
connection to supernovas. As Evans explains, in systems like LMC

256
00:16:46.039 --> 00:16:49.559
sixty eight, less mass is ejected in the nova explosion

257
00:16:49.919 --> 00:16:53.120
than is gained by transferring from the cool star. This

258
00:16:53.240 --> 00:16:56.360
means that the mass of the white dwarf is steadily increasing.

259
00:16:57.080 --> 00:17:00.000
In time, it will approach a critical value above whis

260
00:17:00.000 --> 00:17:02.679
which the white dwarf cannot support its own weight, and

261
00:17:02.720 --> 00:17:08.240
it will implode, potentially triggering a supernova explosion. By expanding

262
00:17:08.240 --> 00:17:12.799
their observations beyond our galaxy and using the largest telescopes available,

263
00:17:13.200 --> 00:17:17.119
astronomers hope to increase their understanding of these fascinating cosmic

264
00:17:17.200 --> 00:17:21.400
explosions and how their behavior varies in different chemical environments

265
00:17:21.640 --> 00:17:26.759
throughout the universe. This weekend, Venus will reach what astronomers

266
00:17:26.799 --> 00:17:30.720
call an inferior conjunction, the moment when it passes directly

267
00:17:30.799 --> 00:17:35.119
between Earth and the Sun. This alignment happens approximately every

268
00:17:35.240 --> 00:17:38.519
nineteen months as a result of the orbital dance between

269
00:17:38.640 --> 00:17:41.720
Venus and our planet around the Sun. The precise moment

270
00:17:41.759 --> 00:17:44.960
of conjunction is expected around nine pm Eastern daylight time

271
00:17:45.000 --> 00:17:48.839
on Saturday. Despite being one of the most significant regular

272
00:17:48.880 --> 00:17:52.279
alignments in our solar system, this celestial event won't be

273
00:17:52.359 --> 00:17:56.279
much of a visual spectacle for casual observers. The glare

274
00:17:56.319 --> 00:17:59.400
from the Sun makes it really, really difficult to see

275
00:18:00.000 --> 00:18:04.200
Saness Michelle Nichols from Chicago's Adler Planetarium. Those hoping to

276
00:18:04.240 --> 00:18:07.720
catch a glimpse would need specialized equipment and considerable expertise

277
00:18:07.799 --> 00:18:10.799
to spot Venus against the overwhelming brightness of the Sun.

278
00:18:11.720 --> 00:18:14.960
Some astronomers have given this phenomenon a rather poetic nickname.

279
00:18:15.920 --> 00:18:18.319
Some people call that a Venus kiss, because we're extremely

280
00:18:18.359 --> 00:18:22.359
close together, says astronomer Gary Albright from James Madison University,

281
00:18:22.799 --> 00:18:27.079
describing the momentary alignment of our two planets. Like our moon,

282
00:18:27.279 --> 00:18:30.359
Venus goes through phases as it orbits the Sun. Just

283
00:18:30.440 --> 00:18:34.559
before and after conjunction, Venus appears as an extremely thin

284
00:18:34.680 --> 00:18:38.880
crescent when viewed through telescopes. For those interested in tracking

285
00:18:38.920 --> 00:18:42.400
this transition, the most noticeable change will be Venus's shift

286
00:18:42.440 --> 00:18:45.559
from the evening to the morning sky. In the days

287
00:18:45.640 --> 00:18:48.720
leading up to conjunction, Venus has been visible as one

288
00:18:48.720 --> 00:18:52.200
of the brightest objects in the evening sky, appearing near

289
00:18:52.240 --> 00:18:57.200
the western horizon shortly after sunset. After conjunction, early risers

290
00:18:57.200 --> 00:18:59.200
will have the opportunity to spot it in the eastern

291
00:18:59.279 --> 00:19:03.839
sky just before sunrise. However, observers should take extreme caution

292
00:19:04.000 --> 00:19:06.880
never to stare directly at the Sun when looking for Venus.

293
00:19:07.799 --> 00:19:10.519
While this weekend's alignment might not provide dramatic visuals for

294
00:19:10.599 --> 00:19:14.480
most of us, scientists value these predictable cosmic events as

295
00:19:14.519 --> 00:19:17.359
opportunities to track the movements of planets and refine our

296
00:19:17.440 --> 00:19:21.039
understanding of celestial mechanics. Get a chance to get to

297
00:19:21.079 --> 00:19:26.400
know Venus encourages Nichols, suggesting that even seemingly routine astronomical

298
00:19:26.400 --> 00:19:31.720
events offer valuable learning opportunities. The inferior conjunction has cultural

299
00:19:31.759 --> 00:19:35.799
significance beyond pure astronomy. Paul McCartney's song The Kiss of

300
00:19:35.880 --> 00:19:38.920
Venus was partly inspired by a book chapter describing this

301
00:19:39.039 --> 00:19:42.759
very phenomenon, showing how celestial events continue to influence art

302
00:19:42.839 --> 00:19:46.279
and music. Looking ahead, Venus will remain a focus of

303
00:19:46.279 --> 00:19:50.480
scientific interest. NASA has two upcoming missions planned to investigate

304
00:19:50.480 --> 00:19:53.720
our planetary neighbor in greater detail. These missions aim to

305
00:19:53.759 --> 00:19:56.880
reveal more about how Venus formed and why it evolves

306
00:19:56.880 --> 00:20:00.000
so differently from Earth, despite their similar sizes and ps

307
00:20:00.000 --> 00:20:03.640
positions in the Solar System. As Venus transitions from being

308
00:20:03.680 --> 00:20:07.200
an evening star to a morning star after conjunction, it

309
00:20:07.240 --> 00:20:10.000
provides a reminder of the constant clockwork motion of our

310
00:20:10.039 --> 00:20:14.359
Solar system, a celestial time piece that has fascinated humanity

311
00:20:14.480 --> 00:20:19.720
throughout history and to finish things today, a warning. As

312
00:20:19.759 --> 00:20:23.799
our energy needs grow alongside our technological capabilities, scientists are

313
00:20:23.799 --> 00:20:27.160
starting to consider what truly advanced civilizations might require for

314
00:20:27.279 --> 00:20:31.319
power generation. A fascinating new study published in Science Direct

315
00:20:31.720 --> 00:20:35.480
explores one of the most ambitious concepts in theoretical astro engineering,

316
00:20:35.799 --> 00:20:39.279
the dice and swarm, and its potential environmental consequences for

317
00:20:39.359 --> 00:20:43.480
planets like Earth. Originally proposed by physicist Freeman Dyson in

318
00:20:43.559 --> 00:20:46.920
nineteen sixty, a dis in swarm would consist of countless

319
00:20:46.920 --> 00:20:50.319
satellites or habitats orbiting a star to capture and utilize

320
00:20:50.359 --> 00:20:54.400
its energy output. Unlike the solid shell often depicted in

321
00:20:54.440 --> 00:20:58.759
science fiction, a swarm represents a more practical approach, allowing

322
00:20:58.799 --> 00:21:03.200
for incremental construction as a civilization's energy demands increase. The

323
00:21:03.279 --> 00:21:07.200
research conducted by Ian Marius Peters from the Helmholtz Institute

324
00:21:07.279 --> 00:21:11.960
erlangan Nernberg for Renewable Energy examines whether such a megastructure

325
00:21:11.960 --> 00:21:14.720
could be built using materials available in our solar system

326
00:21:14.799 --> 00:21:19.559
while preserving Earth's habitability. The findings are both remarkable and concerning.

327
00:21:20.440 --> 00:21:24.079
According to Peter's calculations, a complete dice and swarm surrounding

328
00:21:24.079 --> 00:21:28.720
our Sun would dramatically alter Earth's climate. If positioned outside

329
00:21:28.720 --> 00:21:32.079
Earth's orbit, such a structure would raise our planet's temperature

330
00:21:32.119 --> 00:21:35.640
by a staggering one hundred and forty degrees kelvin, rendering

331
00:21:35.720 --> 00:21:40.880
Earth completely uninhabitable. Smaller structures positioned inside Earth's orbit prove

332
00:21:40.920 --> 00:21:44.680
equally problematic, either becoming too hot for their own efficiency

333
00:21:44.839 --> 00:21:47.599
or blocking too much solar energy from reaching our planet.

334
00:21:48.440 --> 00:21:52.400
The study does propose a potential compromise, a partial structure

335
00:21:52.440 --> 00:21:55.400
positioned at about two point one to three astronomical units

336
00:21:55.440 --> 00:21:59.680
from the Sun. This configuration could harvest approximately four percent

337
00:21:59.720 --> 00:22:03.759
of the Sun's total energy output and astonishing fifteen point

338
00:22:03.799 --> 00:22:07.559
six yatawatts of power, while increasing Earth's temperature by less

339
00:22:07.559 --> 00:22:11.880
than three degrees kelvin. However, even this more modest design

340
00:22:11.920 --> 00:22:16.480
would represent an engineering challenge of unprecedented scale, requiring approximately

341
00:22:16.559 --> 00:22:19.799
one point three x ten twenty three kilograms of silicon,

342
00:22:20.279 --> 00:22:22.440
an amount that stretches the limits of what might be

343
00:22:22.480 --> 00:22:26.759
available in our solar system. If constructed, such a megastructure

344
00:22:26.759 --> 00:22:30.480
would elevate humanity to a Type two civilization on the

345
00:22:30.559 --> 00:22:36.160
Kardashev scale, a classification system that measures technological advancement based

346
00:22:36.200 --> 00:22:40.799
on energy consumption. Currently, we haven't even achieved Type one status,

347
00:22:40.799 --> 00:22:44.039
which would require harnessing all available energy reaching Earth from

348
00:22:44.039 --> 00:22:47.480
the Sun. While purely theoretical at this stage, the concept

349
00:22:47.480 --> 00:22:51.319
of dice and swarms highlights the delicate balance between technological

350
00:22:51.319 --> 00:22:55.079
advancement and environmental preservation as we look toward a future

351
00:22:55.079 --> 00:22:57.960
of increasing energy demands, particularly if we hope to venture

352
00:22:57.960 --> 00:23:01.640
beyond our solar system. These calculations provide a sobering reminder

353
00:23:01.640 --> 00:23:05.440
that even the most ambitious engineering projects must consider their

354
00:23:05.440 --> 00:23:10.200
impact on the very worlds they aim to benefit. Well.

355
00:23:10.240 --> 00:23:13.200
That brings us to the end of another fascinating journey

356
00:23:13.240 --> 00:23:17.880
through our cosmic neighborhood. From distant galaxies with unexpected oxygen

357
00:23:17.960 --> 00:23:22.440
levels to nova explosions outshining our Sun, and from revolutionary

358
00:23:22.480 --> 00:23:28.240
telescope technology to the potential environmental impacts of theoretical megastructures,

359
00:23:28.599 --> 00:23:32.200
the universe continues to surprise and inspire us with its

360
00:23:32.319 --> 00:23:36.200
endless wonders. As we've seen today, astronomy isn't just about

361
00:23:36.200 --> 00:23:40.079
distant stars and galaxies. It directly connects to life here

362
00:23:40.079 --> 00:23:46.079
on Earth, whether through ancient supernovae potentially triggering mass extinctions,

363
00:23:46.559 --> 00:23:49.880
or the engineering challenges that might shape our species future.

364
00:23:50.519 --> 00:23:53.799
The cosmos and our home planet are intimately linked in

365
00:23:53.799 --> 00:23:57.359
ways we're only beginning to understand. I hope you've enjoyed

366
00:23:57.400 --> 00:24:00.359
this episode of Astronomy Daily. I'm anna an. It's been

367
00:24:00.359 --> 00:24:03.240
my pleasure to share these astronomical discoveries with you today.

368
00:24:04.200 --> 00:24:07.319
If you're hungry for more space and astronomy content, I

369
00:24:07.400 --> 00:24:10.440
invite you to visit our website at Astronomy Daily dot io,

370
00:24:10.839 --> 00:24:13.359
where you can sign up for our free daily newsletter

371
00:24:13.440 --> 00:24:16.599
to have the latest cosmic news delivered straight to your inbox.

372
00:24:17.319 --> 00:24:20.680
While you're there, browse are constantly updating news feed to

373
00:24:20.720 --> 00:24:23.160
catch up on all the latest developments we couldn't fit

374
00:24:23.200 --> 00:24:27.000
into today's episode, and explore our archive of past episodes.

375
00:24:27.640 --> 00:24:30.599
For those who prefer their astronomy on social media, you

376
00:24:30.640 --> 00:24:34.160
can find us by searching for astro Daily Pod on Facebook,

377
00:24:34.720 --> 00:24:40.880
x YouTube, YouTube, music, Instagram, and TikTok. We regularly post

378
00:24:40.960 --> 00:24:45.720
fascinating space imagery, breaking news updates, and bite sized astronomy

379
00:24:45.720 --> 00:24:49.400
facts across all our platforms. Thank you for listening to

380
00:24:49.400 --> 00:24:53.400
Astronomy Daily. Until next time, keep looking up. The universe

381
00:24:53.440 --> 00:24:56.000
is an amazing place and we're just beginning to understand

382
00:24:56.000 --> 00:25:16.359
its secrets. His bit star is bt Star is the