Aug. 25, 2026

Stellar Salvage: SpaceX's Starship Recovery and the Age of the Universe

Show Notes
Transcript

SpaceTime Series 29 Episode 102 *SpaceX’s Starship arrives at Christmas Island After some 24 days at sea, a SpaceX recovery team has successfully towed its test flight 13 Starship into the remote Australian Indian Ocean territory of Christmas Island. The unplanned operation was hastily put together after the spacecraft unexpectedly held together following its splashdown off the Western Australian coast. *How old really is the universe? Astronomers have come up with a new way to work out the age of the universe finding it to be 13.6 billion years old – some 200 million years younger than previously thought. *Einstein’s general relativity theory still stands More than 100 years after Albert Einstein published his iconic general theory of relativity, it remains science’s best understanding of gravity and the universe on the cosmic scale. *The Science Report A new study shows that carrying a little extra weight could be beneficial as you get older. People lacking human connections more likely to turn to AI chatbots for companionship. The Southern Ocean and parts of the Pacific may be the best places to fertilise to remove CO2. How dogs have learnt to understand human facial expressions. Alex on Tech: The Galaxy passport sized Z Fold 8 tops the sales figures.

🌏 Get Our Exclusive NordVPN deal here ➼ www.bitesz.com/nordvpn . The discounts and bonuses are incredible! And it’s risk-free with Nord’s 30-day money-back guarantee! ✌ If you’d like to support the podcast and gain access to bonus content by becoming a SpaceTime crew member, you can do just that through The Big Bang editions on Patreon, Spotify and Apple Podcasts. Details on the Support page on our website https://www.bitesz.com/show/spacetime/support/

The Astronomy, Space, Technology & Science News Podcast.

WEBVTT

1
00:00:00.250 --> 00:00:03.919
This is Space Time, Series 29, Episode 102, for broadcast

2
00:00:03.940 --> 00:00:08.199
on the 26th of August, 2026. Coming up on Space Time.

3
00:00:08.919 --> 00:00:13.140
SpaceX's Starship arrives at Christmas Island. A new study looking

4
00:00:13.160 --> 00:00:17.989
at how old our universe really is. And despite more tests,

5
00:00:18.289 --> 00:00:21.730
Albert Einstein's general theory of relativity still stands the test

6
00:00:21.750 --> 00:00:25.980
of time. All that and more coming up on Space Time.

7
00:00:27.429 --> 00:00:30.500
Welcome to Space Time with Stuart Gary.

8
00:00:46.810 --> 00:00:50.390
After some 24 days at sea, a SpaceX recovery team

9
00:00:50.409 --> 00:00:54.049
has successfully towed Starship 40 into sheltered waters on the

10
00:00:54.090 --> 00:00:57.310
leeward side of the remote Australian Indian Ocean territory of

11
00:00:57.399 --> 00:01:01.820
Christmas Island. The unplanned operation had been hastily put together

12
00:01:01.979 --> 00:01:05.739
after the spacecraft unexpectedly held together following its splashdown off

13
00:01:05.780 --> 00:01:09.620
the western Australian coast. Starship 40 had been launched into

14
00:01:09.719 --> 00:01:13.579
orbit on Test Flight 13 from SpaceX's Boa Chica Starbase

15
00:01:13.659 --> 00:01:17.390
on the Texas Gulf Coast. The hour-long test flight saw

16
00:01:17.430 --> 00:01:21.430
the world's largest and most powerful rocket, a 122-meter-tall Starship

17
00:01:21.469 --> 00:01:25.239
Super Heavy, successfully blasted into space and achieve all its

18
00:01:25.319 --> 00:01:28.819
major test goals. The flight used the latest Block III

19
00:01:28.840 --> 00:01:31.870
incarnation of the rocket, together with a new ignition sequence

20
00:01:31.909 --> 00:01:35.709
for its 33 new more powerful Raptor III version engines.

21
00:01:36.409 --> 00:01:39.790
The successful stage separation saw the launch vehicle's first stage,

22
00:01:39.989 --> 00:01:43.189
known as the Super Heavy, carry out a textbook boost-back burn,

23
00:01:43.430 --> 00:01:47.409
returning to Earth and splashing down off the Texas coast. However,

24
00:01:47.650 --> 00:01:50.450
only 10 of the planned 13 Raptors lit up for

25
00:01:50.469 --> 00:01:53.790
the landing burn, with a further two failing shortly afterwards.

26
00:01:54.489 --> 00:01:57.750
Now that meant Super Heavy descended too quickly, and consequently

27
00:01:57.769 --> 00:02:02.519
hit the water much too hard. Meanwhile, the Starship Upper Stage,

28
00:02:02.530 --> 00:02:05.260
known simply as the ship, continued to climb to its

29
00:02:05.319 --> 00:02:09.659
planned suborbital altitude, where it successfully deployed 20 Starlink Version

30
00:02:09.659 --> 00:02:13.199
3 broadband test satellites and also successfully undertook a Raptor

31
00:02:13.280 --> 00:02:17.759
engine restart. It then re-entered the atmosphere, performing a perfect

32
00:02:17.800 --> 00:02:21.300
descent and water landing, gently splashing down and toppling over

33
00:02:21.379 --> 00:02:26.659
into the ocean. However, surprisingly, rather than sinking, it remained buoyant,

34
00:02:26.860 --> 00:02:29.800
bobbing up and down on the waves. Now, that's never

35
00:02:29.840 --> 00:02:33.550
happened before. but it gave SpaceX an opportunity to recover

36
00:02:33.590 --> 00:02:37.930
the vehicle for more detailed examination. See, usually SpaceX engineers

37
00:02:38.110 --> 00:02:40.719
only end up with data from onboard instruments and cameras,

38
00:02:40.960 --> 00:02:43.340
so having the actual spacecraft to look at was a

39
00:02:43.379 --> 00:02:47.979
huge bonus. SpaceX boss Elon Musk quickly organized a recovery

40
00:02:48.039 --> 00:02:52.050
operation with a SpaceX splashdown monitoring ship, Go Astralis, remaining

41
00:02:52.110 --> 00:02:56.620
stationed near ship 40. The splashdown occurred roughly 1,300 kilometres

42
00:02:56.710 --> 00:03:00.650
off the western Australian coast, and so required specialised ocean-going

43
00:03:00.810 --> 00:03:05.629
tugs for the operation. Two tugboats, Norman Ranger and Skimmer Tide,

44
00:03:05.689 --> 00:03:08.310
were contracted and quickly set out from the Australian port

45
00:03:08.349 --> 00:03:12.490
of Dampier to undertake recovery efforts. Norman Ranger is a

46
00:03:12.530 --> 00:03:14.050
big anchor-handling tug.

47
00:03:14.490 --> 00:03:15.009
It's used to.

48
00:03:14.990 --> 00:03:19.020
Dealing with huge quarter-million and half-million tonne iron ore bulk carriers,

49
00:03:19.379 --> 00:03:22.849
so an empty 200-tonne spacecraft shouldn't be a problem. The

50
00:03:22.889 --> 00:03:26.030
problem is Starship wasn't fitted with any anchor points to

51
00:03:26.090 --> 00:03:29.030
attach a tow rope to, and that's where Schematide came in.

52
00:03:29.689 --> 00:03:32.810
It delivered a string of large Yokohama rubber buffer fenders

53
00:03:32.870 --> 00:03:35.710
which would be placed around the spacecraft, encircling it like

54
00:03:35.770 --> 00:03:38.370
a lasso and cushioning it from damage so it could

55
00:03:38.409 --> 00:03:42.340
be towed. These buffer fenders used compressed air to absorb

56
00:03:42.479 --> 00:03:46.819
impact energy during ship-to-ship or ship-to-dock operations, protecting vessels and

57
00:03:46.879 --> 00:03:50.909
port structures from damage. However, the ocean currents and winds

58
00:03:51.009 --> 00:03:53.669
proved to be a major challenge for maneuvering the spacecraft,

59
00:03:53.770 --> 00:03:56.629
which was sitting high in the water. That meant slow

60
00:03:56.789 --> 00:04:00.310
progress and an awfully long journey back to Port Ampere.

61
00:04:01.129 --> 00:04:04.379
Making matters worse, the fenders were damaging the spacecraft's heat

62
00:04:04.400 --> 00:04:06.860
shield tiles, which was one of the key items engineers

63
00:04:06.900 --> 00:04:10.840
wanted to examine. So it was eventually decided to change plans.

64
00:04:11.300 --> 00:04:13.780
Remove the fenders and attach a tow line to one

65
00:04:13.800 --> 00:04:17.230
of the spacecraft's Raptor vacuum engines. and there was still

66
00:04:17.269 --> 00:04:21.670
that ongoing fight against the prevailing winds and swell. Eventually,

67
00:04:21.750 --> 00:04:25.569
SpaceX decided to change course. Instead of heading east to

68
00:04:25.589 --> 00:04:29.069
the Australian mainland, they'd head north to Christmas Island instead,

69
00:04:29.300 --> 00:04:32.759
arriving there a few days ago. The heavy lift ship

70
00:04:32.800 --> 00:04:35.300
Forte has now arrived at Christmas Island to load and

71
00:04:35.339 --> 00:04:39.779
transport Starship. Forte is a semi-submersible, meaning it will flood

72
00:04:39.819 --> 00:04:43.199
its ballast tanks to submerge just enough to allow Starship

73
00:04:43.240 --> 00:04:46.199
to be positioned above its deck. It'll then empty its

74
00:04:46.240 --> 00:04:49.560
ballast tanks again and refloat, lifting the spacecraft out of

75
00:04:49.579 --> 00:04:53.569
the water for transport back to the United States. Needless

76
00:04:53.610 --> 00:04:56.629
to say, NASA's monitoring these events closely, with a version

77
00:04:56.649 --> 00:04:58.930
of Starship called the HLS to be one of the

78
00:04:58.970 --> 00:05:02.430
vehicles used to transport Artemis crew from the Orion spacecraft

79
00:05:02.490 --> 00:05:05.120
down to the lunar surface and back again once manned

80
00:05:05.180 --> 00:05:08.769
operations to the lunar south pole get underway. A test

81
00:05:08.810 --> 00:05:11.589
of those capabilities is slated for next year in low-Earth

82
00:05:11.709 --> 00:05:14.610
orbit using the Artemis III mission, which will attempt docking

83
00:05:14.629 --> 00:05:17.810
a manned Orion capsule with the Starship. And if that

84
00:05:17.870 --> 00:05:20.829
goes well, then a manned lunar landing is likely to

85
00:05:20.870 --> 00:05:25.480
happen in 2028. This is Space Time. Still to come,

86
00:05:25.500 --> 00:05:28.360
a new debate on how old the universe is, and

87
00:05:28.519 --> 00:05:32.959
Einstein's general theory of relativity passes yet another test. All

88
00:05:33.000 --> 00:05:45.629
that and more still to come on Space Time. Astronomers

89
00:05:45.670 --> 00:05:47.290
think they've come up with a new way to work

90
00:05:47.329 --> 00:05:50.439
out the age of the universe, finding it to be 13.6

91
00:05:50.439 --> 00:05:53.680
billion years old. That's some 200 million years younger than

92
00:05:53.740 --> 00:05:57.360
previously thought. The findings reported in the journal Astronomy and

93
00:05:57.399 --> 00:06:01.160
Astrophysics are based on comparing estimates of the universe's age

94
00:06:01.319 --> 00:06:03.819
rather than its expansion rate as a new way to

95
00:06:03.899 --> 00:06:07.660
address the Hubble tension. This question of the Hubble tension,

96
00:06:08.139 --> 00:06:10.879
how quickly the universe is expanding and therefore how old

97
00:06:10.939 --> 00:06:13.459
it is, is one of the most debated topics in

98
00:06:13.519 --> 00:06:17.970
modern cosmology. Local measurements show a faster expansion rate than

99
00:06:18.050 --> 00:06:22.060
predictions calculated from the early universe. And that creates a

100
00:06:22.060 --> 00:06:26.879
statistical mismatch that standard physics simply can't explain. So what

101
00:06:26.899 --> 00:06:30.810
are these two methods? Well, the early universe cosmic microwave

102
00:06:30.870 --> 00:06:34.850
background radiation method uses telescopes to measure the cosmic microwave

103
00:06:34.910 --> 00:06:39.170
background radiation emitted when the first hydrogen atoms formed 280,000

104
00:06:39.170 --> 00:06:42.250
years after the Big Bang, which has now cooled down

105
00:06:42.310 --> 00:06:46.629
to just 2.7 degrees above absolute zero. Running this data

106
00:06:46.689 --> 00:06:50.769
through standard cosmological models predicts an expansion rate, or Hubble constant,

107
00:06:50.910 --> 00:06:55.730
of around 67 to 68 kilometers per second per megaparsec.

108
00:06:56.389 --> 00:06:59.100
On the other hand, the Late Universe Distance Ladder method

109
00:06:59.319 --> 00:07:02.680
uses stars known as Cepheid variables, which all pulsate at

110
00:07:02.759 --> 00:07:05.800
given rates based on their size and hence luminosity, and

111
00:07:05.879 --> 00:07:08.920
Type Ia supernovae, which are all roughly the same mass

112
00:07:09.100 --> 00:07:12.160
and hence explode with the same level of luminosity, thereby

113
00:07:12.279 --> 00:07:15.689
allowing astronomers to use the inverse square law to determine

114
00:07:15.750 --> 00:07:19.069
cosmic distances. It's a bit like looking at a row

115
00:07:19.089 --> 00:07:22.490
of streetlights down a road. They're all the same brightness,

116
00:07:22.569 --> 00:07:25.529
but they look progressively dimmer and dimmer the further away

117
00:07:25.569 --> 00:07:28.509
they are, or in cosmic terms, how fast things are

118
00:07:28.550 --> 00:07:32.269
moving away from you. This shows a faster Hubble constant

119
00:07:32.350 --> 00:07:36.800
of around 73 to 74 kilometers per second per megaparsec.

120
00:07:37.680 --> 00:07:40.300
And no matter how much scientists have tried, they haven't

121
00:07:40.319 --> 00:07:43.420
been able to reconcile the difference between these two measurements.

122
00:07:44.199 --> 00:07:48.660
That's the Hubble tension. Using precise stellar data, the study's

123
00:07:48.779 --> 00:07:52.069
authors determined ages for carefully selected very old Milky Way

124
00:07:52.129 --> 00:07:54.870
stars and concluded the most likely age for the universe

125
00:07:54.910 --> 00:07:58.589
as a whole would be 13.6 billion years. Now that's

126
00:07:58.670 --> 00:08:02.689
much younger than assumptions under standard cosmological models. The age

127
00:08:02.740 --> 00:08:06.600
is inconsistent with a younger universe, implied by Cepheid variable

128
00:08:06.639 --> 00:08:10.399
and supernova-based expansion measurements. But it is compatible with the

129
00:08:10.519 --> 00:08:14.980
older age inferred by observations of the cosmic microwave background radiation,

130
00:08:15.060 --> 00:08:18.660
the leftover heat from the Big Bang. Cosmological models link

131
00:08:18.699 --> 00:08:21.040
the current rate of expansion of the universe directly to

132
00:08:21.100 --> 00:08:23.540
its age, with a higher value of the Hubble constant

133
00:08:23.660 --> 00:08:27.339
implying a younger universe, while a lower value corresponds to

134
00:08:27.360 --> 00:08:29.939
an older one. Of course, the universe can't be any

135
00:08:29.980 --> 00:08:33.009
younger than the oldest stars it contains. and the authors

136
00:08:33.070 --> 00:08:36.820
of this new study use that as their guidestone. So

137
00:08:36.929 --> 00:08:39.220
if the ages of the older stars in our galaxy

138
00:08:39.240 --> 00:08:41.320
can therefore be measured with a high degree of precision,

139
00:08:41.539 --> 00:08:43.720
a robust lower limit for the age of the universe

140
00:08:43.799 --> 00:08:47.419
can be established. The project was initiated by an unusual

141
00:08:47.460 --> 00:08:51.330
collaboration between two research fields that have traditionally been very separate,

142
00:08:51.590 --> 00:08:54.250
a cosmology group from the University of Bologna and a

143
00:08:54.350 --> 00:08:58.549
stellar archaeology group from the Leibniz Institute of Astrophysics in Potsdam.

144
00:08:59.250 --> 00:09:01.399
The work was based on an existing catalogue of stellar

145
00:09:01.480 --> 00:09:04.179
ages from a previous study in which precise ages were

146
00:09:04.220 --> 00:09:07.659
measured by combining multiple pieces of information on the brightness,

147
00:09:07.720 --> 00:09:10.799
position and distance of more than 200,000 stars in the

148
00:09:10.840 --> 00:09:13.909
Milky Way. A crucial element for this study was the

149
00:09:14.009 --> 00:09:16.230
use of the third data release from the Gaia mission,

150
00:09:16.330 --> 00:09:20.110
which provides exceptionally accurate parallaxes and spectra and thus improved

151
00:09:20.169 --> 00:09:24.059
stellar parameters for a large number of nearby stars. From

152
00:09:24.139 --> 00:09:27.519
this combined dataset, a carefully selected group of the oldest

153
00:09:27.580 --> 00:09:31.399
stars with the most reliable age estimates was compiled. The

154
00:09:31.460 --> 00:09:34.440
focus was on quality over quantity, using only stars whose

155
00:09:34.539 --> 00:09:38.200
ages could be determined robustly and by removing potential contaminants.

156
00:09:38.860 --> 00:09:41.500
And with the NEXTGUIDE data release on the horizon, stellar

157
00:09:41.570 --> 00:09:45.690
ages could become a fundamental anchor of cosmology. Now, although

158
00:09:45.730 --> 00:09:48.870
these results are not yet conclusive due to remaining uncertainties

159
00:09:48.950 --> 00:09:52.269
in stellar age estimates, they are providing an important independent

160
00:09:52.309 --> 00:09:55.970
constraint on the debate over the Hubble tension, and consequently,

161
00:09:56.480 --> 00:10:00.580
the age of the universe. This is Space Time. Still

162
00:10:00.600 --> 00:10:04.539
to come, yet another experiment showing Einstein's general theory of

163
00:10:04.600 --> 00:10:08.240
relativity stands the test of time. Later in the science report,

164
00:10:08.580 --> 00:10:11.409
a new study shows how dogs have learnt to understand

165
00:10:11.490 --> 00:10:14.830
human facial expressions. All that and more still to come

166
00:10:15.549 --> 00:10:34.309
on Space-Time. More than a hundred years after Albert Einstein

167
00:10:34.370 --> 00:10:38.210
published his iconic general theory of relativity, it remains science's

168
00:10:38.289 --> 00:10:41.970
best understanding of gravity in the universe on the cosmic scale.

169
00:10:42.210 --> 00:10:46.490
And it's consistently withstood the very best tests scientists can devise.

170
00:10:47.470 --> 00:10:49.450
A report in the journal Science looked at one of

171
00:10:49.490 --> 00:10:52.789
the most comprehensive tests of general relativity near a supermassive

172
00:10:52.809 --> 00:10:57.250
black hole ever undertaken. The study's lead author, Andrea Gentz,

173
00:10:57.309 --> 00:11:00.450
from the University of California, Los Angeles, admits, based on

174
00:11:00.490 --> 00:11:04.509
her data, Einstein is still right. However, she points out

175
00:11:04.549 --> 00:11:08.049
that general relativity still can't fully explain gravity inside a

176
00:11:08.090 --> 00:11:10.720
black hole, and at some point, science will need to

177
00:11:10.769 --> 00:11:14.320
move beyond Einstein's theories to a more comprehensive understanding of

178
00:11:14.379 --> 00:11:18.720
gravity that explains exactly what a black hole is. Einstein's

179
00:11:18.720 --> 00:11:21.720
1915 general theory of relativity holds that what we perceive

180
00:11:21.759 --> 00:11:24.490
as the force of gravity arises from the curvature of

181
00:11:24.590 --> 00:11:28.230
space and time due to mass. Light from a star

182
00:11:28.309 --> 00:11:30.850
is bent by the mass of that star, as well

183
00:11:30.889 --> 00:11:33.649
as any other stars or objects as photons of light

184
00:11:33.730 --> 00:11:37.509
pass by. And it's not just light, even time changes

185
00:11:37.549 --> 00:11:40.850
due to mass and velocity. So Einstein's theory remains the

186
00:11:40.870 --> 00:11:44.830
best description science has of how gravity works. And these

187
00:11:44.870 --> 00:11:48.279
laws of physics, including gravity, should be valid everywhere in

188
00:11:48.320 --> 00:11:53.019
the universe. To test that, Jensen colleagues observed a star

189
00:11:53.039 --> 00:11:57.039
known as SO2 as it orbits Sagittarius A-star, the supermassive

190
00:11:57.059 --> 00:11:59.539
black hole at the center of our galaxy, the Milky Way.

191
00:12:00.230 --> 00:12:05.570
Located some 27,000 light-years away, Sagittarius A-star has some 4.3

192
00:12:05.570 --> 00:12:08.009
million times the mass of our Sun, and it's the

193
00:12:08.090 --> 00:12:12.620
pivot point around which our entire galaxy revolves. The star

194
00:12:12.850 --> 00:12:16.750
SO2 takes some 16 years to complete each orbit around

195
00:12:16.830 --> 00:12:20.309
Sagittarius A star, travelling at speeds of over 26 million

196
00:12:20.350 --> 00:12:23.549
kilometres an hour during its closest approach to the black hole.

197
00:12:24.230 --> 00:12:27.769
So Goetz and colleagues watched as this star undertook its

198
00:12:27.870 --> 00:12:31.309
orbital voyage, and they analysed the spectra coming from the

199
00:12:31.350 --> 00:12:34.200
star as it made its closest approach to the black hole.

200
00:12:34.950 --> 00:12:37.629
Spectra is the rainbow of light produced by the star,

201
00:12:37.710 --> 00:12:40.730
and it displays a series of so-called spectral lines, which

202
00:12:40.769 --> 00:12:43.750
provide a signature of the chemicals that make up that star.

203
00:12:44.450 --> 00:12:47.090
As well as its composition, spectra also tell you how

204
00:12:47.169 --> 00:12:49.710
luminous a star is. The thicker the spectral lines, the

205
00:12:49.750 --> 00:12:52.509
hotter the star. It can even tell you how fast

206
00:12:52.549 --> 00:12:55.039
the star is moving towards or away from you thanks

207
00:12:55.080 --> 00:12:58.539
to a Doppler shift in its spectral lines. Objects moving

208
00:12:58.620 --> 00:13:01.580
away have their spectral lines shifted towards the red end

209
00:13:01.600 --> 00:13:05.429
of the spectrum, redshifted. While objects moving towards you have

210
00:13:05.470 --> 00:13:07.769
those lines shifted towards the blue end of the spectrum,

211
00:13:07.850 --> 00:13:11.029
blue shifted. And how far those lines are shifted tells

212
00:13:11.049 --> 00:13:13.730
you how fast that object's moving towards or away from you.

213
00:13:14.330 --> 00:13:17.470
Goetz and colleagues took measurements of SO2 roughly every four

214
00:13:17.549 --> 00:13:20.289
nights during crucial periods of the star's orbit over a

215
00:13:20.289 --> 00:13:24.649
24-year period, using observations from the Keck Observatory at Topamanakeo

216
00:13:24.809 --> 00:13:29.009
as well as the Gemini and Subaru telescopes. Combined, this

217
00:13:29.090 --> 00:13:32.000
data allowed the authors to test general relativity to an

218
00:13:32.139 --> 00:13:36.320
unprecedented level. The authors were able to see a commingling

219
00:13:36.360 --> 00:13:40.139
of space and time near the supermassive black hole. Now,

220
00:13:40.200 --> 00:13:43.159
in Newton's version of gravity, space and time are separate.

221
00:13:43.299 --> 00:13:47.269
They do not commingle. But under Einstein, they get completely

222
00:13:47.309 --> 00:13:50.809
commingled near the black hole. Einstein had reported that in

223
00:13:50.830 --> 00:13:53.250
this region close to the black hole, photons have to

224
00:13:53.269 --> 00:13:56.529
do extra work. Their wavelength as they leave the star

225
00:13:56.629 --> 00:13:59.049
depends not only on how fast the star is moving,

226
00:13:59.129 --> 00:14:01.820
but also how much energy the photons expend to escape

227
00:14:01.860 --> 00:14:05.509
the black hole's powerful gravitational pull. Gett says while this

228
00:14:05.529 --> 00:14:07.600
tells us what happens on the universe side of the

229
00:14:07.629 --> 00:14:10.480
event horizon of a black hole, it doesn't explain what's

230
00:14:10.519 --> 00:14:14.000
going on between the event horizon and the singularity, the

231
00:14:14.059 --> 00:14:16.559
point of infinite density in zero volume.

232
00:14:16.759 --> 00:14:21.950
Black holes are deceptively simple and yet incredibly complex. A

233
00:14:23.509 --> 00:14:25.669
black hole is a region of space where the pull

234
00:14:25.710 --> 00:14:30.289
of gravity is so intense that nothing can escape, not

235
00:14:30.350 --> 00:14:38.919
even light. Music We don't have the physics to describe

236
00:14:38.950 --> 00:14:41.809
what a black hole is because it leads to a paradox,

237
00:14:41.950 --> 00:14:50.750
a breakdown in our understanding of how the universe works.

238
00:14:52.009 --> 00:14:55.370
We only have four fundamental forces to describe how the

239
00:14:55.409 --> 00:15:00.269
universe works. Gravity of those four is probably the one

240
00:15:00.289 --> 00:15:03.129
that we have the most intuition for. You throw something up,

241
00:15:03.450 --> 00:15:07.720
it comes back down. but it's actually the least explored.

242
00:15:07.740 --> 00:15:14.779
Einstein really recognized that gravitational fields are equivalent to talking

243
00:15:14.840 --> 00:15:18.360
about space and time not being separate entities.

244
00:15:20.240 --> 00:15:24.559
Einstein noticed that in certain situations, Newtonian laws of physics

245
00:15:24.980 --> 00:15:28.399
don't seem to hold. And that's why Einstein developed his

246
00:15:28.539 --> 00:15:32.269
theory of general relativity. We know that general relativity may

247
00:15:32.330 --> 00:15:35.179
not be a complete description of physics, and so in

248
00:15:35.220 --> 00:15:38.039
order to figure out where it's incomplete, you want to

249
00:15:38.100 --> 00:15:41.500
test it in regions that people haven't tested before. So

250
00:15:41.840 --> 00:15:44.779
people have tested general relativity on Earth, in the solar system,

251
00:15:45.139 --> 00:15:47.450
but never around a black hole that's four million times

252
00:15:47.490 --> 00:15:48.269
the mass of the Sun.

253
00:15:49.669 --> 00:15:52.350
The first question I was interested in was, is there

254
00:15:52.370 --> 00:15:54.629
a supermassive black hole at the center of our galaxy?

255
00:15:55.570 --> 00:15:57.590
If you had asked me would I still be doing

256
00:15:57.610 --> 00:16:00.649
this project, 20 odd years later when we first started,

257
00:16:00.789 --> 00:16:05.659
I would have just laughed at you. I grew up

258
00:16:05.720 --> 00:16:08.700
hearing the word no all the time. You're a girl,

259
00:16:08.960 --> 00:16:11.759
you can't do it. You're a girl, there's no way

260
00:16:11.779 --> 00:16:14.350
you can get into MIT. There's no way you can

261
00:16:14.370 --> 00:16:20.629
get into Caltech. I think I developed a passion for

262
00:16:20.730 --> 00:16:27.149
proving people wrong. We have been able to increase the

263
00:16:27.470 --> 00:16:31.990
evidence for supermassive black holes by a factor of 10 million.

264
00:16:34.809 --> 00:16:37.649
And we have done this by watching how stars move.

265
00:16:41.149 --> 00:16:43.700
My favorite star, its name is SO2, and it makes

266
00:16:43.779 --> 00:16:48.139
its journey every 16 years. We're at this point where

267
00:16:48.279 --> 00:16:51.379
it's closest to the black hole and is experiencing the

268
00:16:51.460 --> 00:16:56.659
strongest pull of gravity. So we have this first opportunity

269
00:16:56.740 --> 00:17:00.539
to get a direct measurement of how Einstein's theory of

270
00:17:00.590 --> 00:17:04.069
general relativity works near a supermassive black hole.

271
00:17:06.470 --> 00:17:10.230
What we've found this summer is that general relativity does

272
00:17:10.819 --> 00:17:14.559
actually describe the motion of the stars around the supermassive

273
00:17:14.599 --> 00:17:15.059
black hole.

274
00:17:17.069 --> 00:17:21.210
That's a transformational change in our understanding about not only

275
00:17:21.250 --> 00:17:25.230
the existence of supermassive black holes, but the physics and

276
00:17:25.369 --> 00:17:27.569
astrophysics associated with black holes.

277
00:17:29.230 --> 00:17:33.339
Andrea, to me, is a brilliant scientist. Her dedication and

278
00:17:33.410 --> 00:17:36.900
her persistence really has been at heart of this project

279
00:17:37.160 --> 00:17:40.160
in order to have the patience and the level of

280
00:17:40.180 --> 00:17:41.779
detail required to do this work.

281
00:17:45.039 --> 00:17:46.259
When I was young I wanted to be the first

282
00:17:46.279 --> 00:17:48.339
woman on the moon, but I think at the same

283
00:17:48.380 --> 00:17:53.519
time I also wanted to be a ballerina. I just

284
00:17:53.539 --> 00:17:59.029
became much more infatuated with the ideas rather than the

285
00:17:59.069 --> 00:18:05.470
physicality of moving myself. It's very poetic that we actually

286
00:18:05.670 --> 00:18:09.769
see the stars in motion doing this dance around the

287
00:18:09.809 --> 00:18:13.349
black hole. So what we want to do is we

288
00:18:13.369 --> 00:18:16.150
want to improve our ability to see a star like

289
00:18:16.190 --> 00:18:19.150
our sun at the center of the galaxy. Because I

290
00:18:19.170 --> 00:18:23.150
think that's when we'll have the full view of how

291
00:18:23.210 --> 00:18:31.180
this dance really works.

292
00:18:32.119 --> 00:18:35.640
That's Andrea Goetz and Tuan Du from the University of California,

293
00:18:35.680 --> 00:18:54.859
Los Angeles. And this is Space Time. And time now

294
00:18:54.880 --> 00:18:56.420
to take another brief look at some of the other

295
00:18:56.460 --> 00:18:59.460
stories making use in science this week with a science report.

296
00:19:00.349 --> 00:19:02.569
A new study has shown that carrying a little extra

297
00:19:02.630 --> 00:19:05.430
weight could be beneficial as you get older, but not

298
00:19:05.490 --> 00:19:08.369
if it's a bigger tummy. A report in the Journal

299
00:19:08.390 --> 00:19:11.369
of the American Geriatric Society claims the new findings are

300
00:19:11.470 --> 00:19:15.730
further pushing the disparity between body mass indexes and waist circumference.

301
00:19:16.390 --> 00:19:18.809
They say having a higher body mass index when you're

302
00:19:18.849 --> 00:19:22.039
older has been linked to a significantly lower risk of dying,

303
00:19:22.180 --> 00:19:24.859
whereas a bigger belly is linked to the opposite. The

304
00:19:24.880 --> 00:19:28.579
researchers looked at data from 7,000 adults aged 65 or

305
00:19:28.700 --> 00:19:31.960
older finding overweight men and men with obesity, that's a

306
00:19:32.000 --> 00:19:35.299
BMI of 30 to less than 40, had a 46

307
00:19:35.299 --> 00:19:38.519
to 51 percent lower risk of mortality compared to those

308
00:19:38.589 --> 00:19:42.259
of normal weight. However, a higher waist circumference was linked

309
00:19:42.299 --> 00:19:45.680
to a 24% increased risk of mortality in men, with

310
00:19:45.759 --> 00:19:50.089
similar patterns seen in women. A new study claims that

311
00:19:50.140 --> 00:19:52.890
people who lack human connections tend to be more likely

312
00:19:52.950 --> 00:19:57.269
to use an artificial intelligent chatbot for companionship. A report

313
00:19:57.309 --> 00:20:00.730
in the journal Nature Human Behavior looked at 237 people's

314
00:20:00.829 --> 00:20:05.049
use of AI chatbots, specifically character AI, a widely used platform,

315
00:20:05.210 --> 00:20:07.890
and found people with fewer friends were more likely to

316
00:20:08.029 --> 00:20:10.990
end up using chatbots for companionship, which was in turn

317
00:20:11.150 --> 00:20:16.259
linked to worse self-reported well-being. The link between AI companionship

318
00:20:16.400 --> 00:20:19.180
and poor well-being was strongest among people who had more

319
00:20:19.259 --> 00:20:22.619
intense relationships with the AI and those who disclosed their

320
00:20:22.640 --> 00:20:27.420
most personal information during their chats. A new study has

321
00:20:27.460 --> 00:20:29.640
found that the Great Southern Ocean, as well as parts

322
00:20:29.680 --> 00:20:31.920
of the Pacific Ocean near the equator, may be the

323
00:20:32.000 --> 00:20:34.920
best places on Earth to fertilize if humans want to

324
00:20:34.960 --> 00:20:37.400
remove most of the carbon dioxide in the atmosphere while

325
00:20:37.440 --> 00:20:41.869
minimizing the impact on the environment. Fertilizing the ocean involves

326
00:20:42.009 --> 00:20:45.289
adding iron to stimulate photoplankton to grow, which in turn

327
00:20:45.369 --> 00:20:49.140
removes carbon dioxide from the atmosphere. The authors compared the

328
00:20:49.180 --> 00:20:51.380
most likely amount of carbon that could be removed by

329
00:20:51.480 --> 00:20:54.390
fertilizing different parts of the oceans around the world, and

330
00:20:54.410 --> 00:20:57.430
they also looked at the environmental impact fertilization would have.

331
00:20:58.089 --> 00:21:00.769
The findings, reported in the journal Nature, claim that the

332
00:21:00.849 --> 00:21:04.430
Southern Ocean offers the best balance between ecological disturbance and

333
00:21:04.529 --> 00:21:10.839
carbon dioxide removal from the atmosphere, followed by the equatorial Pacific. Well,

334
00:21:10.880 --> 00:21:13.180
if you have a four-legged friend with a waggly tail

335
00:21:13.240 --> 00:21:15.859
and a wet nose, you probably already know dogs can

336
00:21:15.900 --> 00:21:20.279
distinguish quite well between different facial expressions, including anger, sadness

337
00:21:20.299 --> 00:21:23.900
and fear. And now new research has finally worked out

338
00:21:23.960 --> 00:21:27.640
what's going on. The findings reported in the journal iScience

339
00:21:27.849 --> 00:21:30.549
are based on brain scans of 12 dogs showing that

340
00:21:30.589 --> 00:21:33.309
specific regions of their brains were active when they saw

341
00:21:33.369 --> 00:21:37.039
happy faces compared to neutral negative ones. Now, one of

342
00:21:37.059 --> 00:21:40.099
these brain regions is also associated with reward, which the

343
00:21:40.180 --> 00:21:43.160
authors think suggests that happy human faces may be emotionally

344
00:21:43.220 --> 00:21:46.880
significant to dogs. They also found differences in dogs' brain

345
00:21:46.920 --> 00:21:49.720
activity when they saw angry and fearful faces, small as

346
00:21:49.839 --> 00:21:53.099
sad versus fearful faces, but no difference between sad and

347
00:21:53.180 --> 00:21:56.980
angry expressions. The study shows that man's best friend has

348
00:21:57.019 --> 00:22:01.039
evolved the social skills necessary to understand and cooperate with people.

349
00:22:01.380 --> 00:22:05.710
The best way to know who's a good boy. Samsung's

350
00:22:05.750 --> 00:22:09.380
new passport-sized Galaxy Z Fold 8 has outsold its more

351
00:22:09.420 --> 00:22:12.920
conventionally proportioned Galaxy Z Fold 8 Ultra during its first

352
00:22:12.960 --> 00:22:16.970
weeks on the market with 51% of sales. With the details,

353
00:22:16.990 --> 00:22:21.279
we're joined by technology editor Alex Saharov-Royd from TechAdvice.life.

354
00:22:21.519 --> 00:22:24.519
It just went on sale and already in Australia, the

355
00:22:24.759 --> 00:22:27.099
passport size one with the widescreen version as opposed to

356
00:22:27.119 --> 00:22:30.259
the one that's square, that has narrowly outsold the square one.

357
00:22:30.420 --> 00:22:33.700
And that's because it's wider. Think of a wider iPhone

358
00:22:33.740 --> 00:22:36.450
mini style device that can then unfold into the 7.6

359
00:22:36.450 --> 00:22:41.789
inch widescreen tablet. I went out and purchased the Z Fold,

360
00:22:42.210 --> 00:22:45.609
and it is fantastic, the Z Fold 8, not the Ultra,

361
00:22:45.630 --> 00:22:47.619
which is the one that's square. So it's been really,

362
00:22:47.779 --> 00:22:50.359
really cool. I mean, everyone marvels at it. The crease

363
00:22:50.400 --> 00:22:53.400
is effectively no longer there. I mean, you can still

364
00:22:53.500 --> 00:22:54.740
see it if you hold it to the lightness. a

365
00:22:54.759 --> 00:22:57.309
certain way, you can just feel it. But compared to

366
00:22:57.329 --> 00:22:59.450
foldable phones from a couple of years ago where you

367
00:22:59.490 --> 00:23:01.930
could really feel this dip in the center of the

368
00:23:01.970 --> 00:23:04.779
screen when you moved your finger across, effectively the crease

369
00:23:04.819 --> 00:23:06.680
is gone. And this is what Apple has been waiting

370
00:23:06.700 --> 00:23:09.359
for for the last eight years for screens to get

371
00:23:09.400 --> 00:23:12.880
into this state. Now, interestingly, Apple will launch its iPhone

372
00:23:12.920 --> 00:23:14.970
Fold or iPhone Ultra, whatever it's going to be called,

373
00:23:15.329 --> 00:23:17.910
in about three weeks' time. But the latest rumors say,

374
00:23:17.990 --> 00:23:20.650
because of the rampocalypse, because of the super high expensive

375
00:23:20.670 --> 00:23:24.710
prices for SSDs, that Apple will showcase it. They'll launch

376
00:23:24.750 --> 00:23:26.710
it in the U.S. first, but it won't come to

377
00:23:26.730 --> 00:23:29.390
the rest of the world until the first quarter or

378
00:23:29.410 --> 00:23:32.069
the second quarter of next year. And we've got Omdia,

379
00:23:32.369 --> 00:23:35.690
who's predicting that by 2028, shipments of these phones will

380
00:23:35.730 --> 00:23:38.920
double to 36 million units. So there's going to be

381
00:23:38.940 --> 00:23:41.480
a huge boom. I mean, already you see people with

382
00:23:41.500 --> 00:23:43.119
these folding phones, but there's going to be so many

383
00:23:43.160 --> 00:23:45.339
more of them. And gone are the days when the

384
00:23:45.359 --> 00:23:48.869
folding phones feel like two smartphones stuck together, this big,

385
00:23:48.950 --> 00:23:52.250
thick thing in your hand. The current smartphones, when they

386
00:23:52.430 --> 00:23:56.059
fold shut, the foldable phones, will feel like an ordinary smartphone.

387
00:23:56.470 --> 00:23:56.710
Phone.

388
00:23:56.750 --> 00:23:58.569
They feel like the thickness of a normal phone. And

389
00:23:58.589 --> 00:24:02.440
then they open up into this glorious landscape. And I'm

390
00:24:02.460 --> 00:24:04.740
just in love. I love this phone factor. It is

391
00:24:04.940 --> 00:24:06.359
stunningly good and cool.

392
00:24:06.420 --> 00:24:07.420
What about the trifold?

393
00:24:07.480 --> 00:24:11.759
Well, with the trifold phones, I was in Shenzhen in 2024,

394
00:24:11.759 --> 00:24:14.359
and I actually saw one of these phones in a

395
00:24:14.440 --> 00:24:15.180
Huawei store.

396
00:24:15.319 --> 00:24:17.799

Stellar Salvage: SpaceX's Starship Recovery and the Age of the Universe

Listen On

Featured Episodes

Recent Episodes

Support On

Stellar Salvage: SpaceX's Starship Recovery and the Age of the Universe

Astronomy Daily Newsletter

Thank you!

Listen On

Featured Episodes

Recent Episodes

Support On