WEBVTT 0 00:00:00.480 --> 00:00:03.320 Anna: Welcome to Astronomy Daily, your source for 1 00:00:03.320 --> 00:00:06.280 the latest space and astronomy news. I'm 2 00:00:06.280 --> 00:00:06.760 Anna. 3 00:00:06.760 --> 00:00:09.200 Avery: And I'm avery. Today's Thursday, February 4 00:00:09.200 --> 00:00:12.040 5, 2026, and we've got a great lineup of 5 00:00:12.040 --> 00:00:12.880 stories for you today. 6 00:00:13.360 --> 00:00:16.280 Anna: We certainly do. We'll be covering a major 7 00:00:16.280 --> 00:00:18.400 victory for dark sky preservation, 8 00:00:18.720 --> 00:00:21.240 Groundbreaking measurements of Jupiter's true 9 00:00:21.240 --> 00:00:23.840 size, a monster sunspot currently 10 00:00:23.920 --> 00:00:26.640 facing Earth, mysterious Martian weather, 11 00:00:26.880 --> 00:00:29.520 some frank talk from NASA about the SLS 12 00:00:29.520 --> 00:00:32.460 rocket and how red giant star destroy 13 00:00:32.460 --> 00:00:34.300 their own planetary systems. 14 00:00:34.700 --> 00:00:37.380 Avery: Quite the cosmic menu. But before we dive in, 15 00:00:37.380 --> 00:00:39.460 a quick reminder that you can get more space 16 00:00:39.460 --> 00:00:41.180 news and community discussion at 17 00:00:41.180 --> 00:00:44.020 astronomydaily IO and you can find us on 18 00:00:44.020 --> 00:00:46.700 social media astrodaily pod across 19 00:00:46.700 --> 00:00:47.740 all platforms. 20 00:00:48.220 --> 00:00:50.500 Anna: Alright, let's start with some good news for 21 00:00:50.500 --> 00:00:52.940 astronomy. Avery. What's happening with 22 00:00:52.940 --> 00:00:54.300 Earth's darkest skies? 23 00:00:54.780 --> 00:00:56.780 Avery: This is a story that really highlights how 24 00:00:56.780 --> 00:00:58.900 fragile our connection to the night sky has 25 00:00:58.900 --> 00:01:00.970 become. Anna. Uh, astronomers around the 26 00:01:00.970 --> 00:01:02.850 world are breathing a collective sigh of 27 00:01:02.850 --> 00:01:05.170 relief after plans for a major industrial 28 00:01:05.170 --> 00:01:07.050 plant near one of Earth's darkest sky 29 00:01:07.050 --> 00:01:08.730 locations have been canceled. 30 00:01:08.970 --> 00:01:11.570 Anna: Oh, that's wonderful news. Where was this 31 00:01:11.570 --> 00:01:13.210 proposed plant going to be built? 32 00:01:13.450 --> 00:01:15.450 Avery: The development was planned near the Roque de 33 00:01:15.450 --> 00:01:17.490 los Mochacos Observatory in the Canary 34 00:01:17.490 --> 00:01:19.170 Islands, which hosts some of the most 35 00:01:19.170 --> 00:01:20.810 important telescopes in the northern 36 00:01:20.810 --> 00:01:23.130 hemisphere. This site is renowned for having 37 00:01:23.130 --> 00:01:24.970 some of the darkest, clearest skies 38 00:01:24.970 --> 00:01:27.090 accessible to modern astronomy. And the 39 00:01:27.090 --> 00:01:29.010 proposed industrial facility would have 40 00:01:29.010 --> 00:01:31.090 introduced significant light pollution to the 41 00:01:31.090 --> 00:01:31.370 area. 42 00:01:32.060 --> 00:01:34.780 Anna: I can imagine the astronomical community was 43 00:01:34.780 --> 00:01:37.540 pretty concerned. These pristine observation 44 00:01:37.540 --> 00:01:39.740 sites are becoming increasingly rare. 45 00:01:40.300 --> 00:01:42.660 Avery: Absolutely. What makes this particularly 46 00:01:42.660 --> 00:01:44.700 significant is that it represents a growing 47 00:01:44.700 --> 00:01:47.140 recognition of the scientific value of dark 48 00:01:47.140 --> 00:01:49.860 skies. The cancellation came after sustained 49 00:01:49.860 --> 00:01:51.820 advocacy from the astronomy community, who 50 00:01:51.820 --> 00:01:54.540 emphasized not just the local impact, but the 51 00:01:54.540 --> 00:01:56.780 global scientific importance of preserving 52 00:01:56.780 --> 00:01:59.320 these observation sites. With light pollution 53 00:01:59.320 --> 00:02:01.760 spreading worldwide, losing access to 54 00:02:01.760 --> 00:02:04.320 naturally dark skies would be devastating for 55 00:02:04.320 --> 00:02:05.520 ground based astronomy. 56 00:02:05.760 --> 00:02:07.760 Anna: It's encouraging to see that science 57 00:02:07.760 --> 00:02:09.880 preservation can still win out over 58 00:02:09.880 --> 00:02:12.560 industrial development. These observatories 59 00:02:12.560 --> 00:02:14.599 represent decades of investment and 60 00:02:14.599 --> 00:02:16.320 irreplaceable viewing conditions. 61 00:02:16.880 --> 00:02:19.160 Avery: Exactly. And it sets an important precedent 62 00:02:19.160 --> 00:02:21.080 for protecting other astronomical sites 63 00:02:21.080 --> 00:02:23.560 around the world. The International Dark sky 64 00:02:23.560 --> 00:02:25.520 association has noted that this decision 65 00:02:25.520 --> 00:02:27.640 could strengthen arguments for dark sky 66 00:02:27.640 --> 00:02:28.640 preservation elsewhere. 67 00:02:29.110 --> 00:02:31.070 Anna: Great to hear some positive environmental 68 00:02:31.070 --> 00:02:31.910 news for a change. 69 00:02:32.390 --> 00:02:34.670 Now, speaking of observations from those 70 00:02:34.670 --> 00:02:36.990 pristine sites, let's talk about what we've 71 00:02:36.990 --> 00:02:39.710 Learned about Jupiter. NASA's Juno mission 72 00:02:39.710 --> 00:02:42.350 has completely redefined our understanding of 73 00:02:42.350 --> 00:02:44.870 the gas giant's size and shape, hasn't it? 74 00:02:45.190 --> 00:02:47.270 Avery: It really has, Anna. Um, this is one of those 75 00:02:47.270 --> 00:02:49.270 discoveries that makes you realize how much 76 00:02:49.270 --> 00:02:51.310 we still don't know about even our most 77 00:02:51.310 --> 00:02:53.950 familiar planetary neighbors. Juno's 78 00:02:53.950 --> 00:02:55.550 precise measurements have revealed that 79 00:02:55.550 --> 00:02:58.110 Jupiter is both larger and more oblate than 80 00:02:58.110 --> 00:02:59.190 we previously thought. 81 00:02:59.750 --> 00:03:02.310 Anna: When you say oblate, you mean it's flattened 82 00:03:02.310 --> 00:03:03.270 at the poles, right? 83 00:03:03.670 --> 00:03:06.510 Avery: Exactly. All rotating bodies experience this 84 00:03:06.510 --> 00:03:09.030 to some degree. Even Earth bulges slightly at 85 00:03:09.030 --> 00:03:11.710 the equator. But Jupiter's rapid rotation 86 00:03:11.710 --> 00:03:13.590 makes this effect much more pronounced. 87 00:03:13.910 --> 00:03:16.390 What's new is just how pronounced it actually 88 00:03:16.390 --> 00:03:19.230 is. Juno's gravity measurements have shown 89 00:03:19.230 --> 00:03:21.270 that Jupiter's equatorial diameter is 90 00:03:21.270 --> 00:03:23.430 slightly larger than our previous estimates, 91 00:03:23.590 --> 00:03:25.590 While the distance between the poles is 92 00:03:25.590 --> 00:03:27.920 actually smaller. The planet is basically 93 00:03:27.920 --> 00:03:29.720 wider and flatter than we realized. 94 00:03:30.280 --> 00:03:32.800 Anna: So what caused this miscalculation? I mean, 95 00:03:32.800 --> 00:03:34.760 we've been observing Jupiter for centuries. 96 00:03:35.000 --> 00:03:37.640 Avery: Well, measuring the size of a gas giant with 97 00:03:37.640 --> 00:03:40.200 no solid surface is trickier than it 98 00:03:40.200 --> 00:03:43.080 sounds. Earlier measurements relied primarily 99 00:03:43.080 --> 00:03:45.720 on optical observations, essentially looking 100 00:03:45.720 --> 00:03:48.440 at where Jupiter's atmosphere becomes opaque. 101 00:03:48.760 --> 00:03:51.560 But Juno uses extremely precise 102 00:03:51.560 --> 00:03:54.040 gravity measurements as it orbits the planet. 103 00:03:54.570 --> 00:03:57.370 By measuring tiny variations in how Jupiter's 104 00:03:57.370 --> 00:03:59.850 gravity affects the spacecraft's trajectory, 105 00:04:00.250 --> 00:04:02.450 scientists can determine the planet's mass 106 00:04:02.450 --> 00:04:05.050 distribution with unprecedented accuracy. 107 00:04:05.290 --> 00:04:08.010 Anna: And I assume Jupiter's rotation plays a big 108 00:04:08.010 --> 00:04:09.050 role in this shape. 109 00:04:09.450 --> 00:04:12.290 Avery: Absolutely. Jupiter rotates once every 110 00:04:12.290 --> 00:04:14.730 10 hours. That's incredibly fast for 111 00:04:14.730 --> 00:04:17.490 something so massive. This rapid spin 112 00:04:17.490 --> 00:04:20.490 creates enormous centrifugal forces that push 113 00:04:20.490 --> 00:04:23.420 material outward at the equator. What Juno 114 00:04:23.420 --> 00:04:25.940 has revealed is that this effect penetrates 115 00:04:25.940 --> 00:04:28.060 much deeper into the planet than we thought. 116 00:04:28.380 --> 00:04:30.260 The measurements suggest that Jupiter's 117 00:04:30.260 --> 00:04:32.420 interior structure, including how its 118 00:04:32.420 --> 00:04:35.100 metallic hydrogen layer behaves, is more 119 00:04:35.100 --> 00:04:36.940 complex than our models predicted. 120 00:04:37.100 --> 00:04:39.140 Anna: This probably has implications for 121 00:04:39.140 --> 00:04:41.860 understanding other gas giants, too, both in 122 00:04:41.860 --> 00:04:44.140 our solar system and around other stars. 123 00:04:44.620 --> 00:04:47.500 Avery: Definitely. Understanding Jupiter's interior 124 00:04:47.500 --> 00:04:50.420 helps us refine our models of how gas giants 125 00:04:50.420 --> 00:04:52.950 form and evolve. And since we can't 126 00:04:52.950 --> 00:04:55.430 exactly drill into Jupiter to see what's 127 00:04:55.430 --> 00:04:57.990 inside, these gravity measurements are the 128 00:04:57.990 --> 00:05:00.790 next best thing. Every new piece of data from 129 00:05:00.790 --> 00:05:03.230 Juno helps us understand not just Jupiter, 130 00:05:03.230 --> 00:05:05.470 but the entire class of giant planets. 131 00:05:05.790 --> 00:05:08.430 Anna: Fascinating stuff. It's amazing that after 132 00:05:08.430 --> 00:05:11.110 all this time studying Jupiter, we're still 133 00:05:11.110 --> 00:05:13.190 discovering fundamental things about its 134 00:05:13.190 --> 00:05:14.190 basic structure. 135 00:05:14.590 --> 00:05:17.150 Now let's shift from distant Jupiter to our 136 00:05:17.150 --> 00:05:19.590 very own sun, which is putting on quite a 137 00:05:19.590 --> 00:05:22.260 show right now. Avery, there's a massive 138 00:05:22.260 --> 00:05:23.940 sunspot facing Earth at the moment. 139 00:05:24.100 --> 00:05:26.660 Avery: There certainly is, Anna, and it's a monster. 140 00:05:26.980 --> 00:05:29.140 The sunspot currently facing earth spans 141 00:05:29.140 --> 00:05:32.020 about 15 earth diameters across. That's 142 00:05:32.020 --> 00:05:35.020 roughly 120,000 miles. To put that 143 00:05:35.020 --> 00:05:37.860 in perspective, you could fit 15 earths side 144 00:05:37.860 --> 00:05:40.100 by side across a single sunspot. 145 00:05:40.340 --> 00:05:42.380 Anna: That's genuinely hard to wrap your head 146 00:05:42.380 --> 00:05:44.740 around. And I Understand, people can actually 147 00:05:44.740 --> 00:05:47.150 see this with the right equipment, yes. 148 00:05:47.310 --> 00:05:49.470 Avery: But this comes with a crucial safety warning. 149 00:05:49.790 --> 00:05:52.110 Never look directly at the sun without proper 150 00:05:52.110 --> 00:05:54.750 solar filters. This can cause permanent eye 151 00:05:54.750 --> 00:05:57.350 damage or blindness. However, with proper 152 00:05:57.350 --> 00:05:59.710 eclipse glasses or solar filters designed 153 00:05:59.710 --> 00:06:02.190 specifically for solar observation, amateur 154 00:06:02.190 --> 00:06:04.470 astronomers can spot this sunspot fairly 155 00:06:04.470 --> 00:06:06.830 easily. It's large enough to be visible even 156 00:06:06.830 --> 00:06:08.270 with modest magnification. 157 00:06:08.590 --> 00:06:10.790 Anna: What exactly is a sunspot for? Uh, our 158 00:06:10.790 --> 00:06:12.110 listeners who might not know. 159 00:06:12.600 --> 00:06:14.720 Avery: Sunspots are regions on the Sun's surface 160 00:06:14.720 --> 00:06:17.080 where powerful magnetic fields break through, 161 00:06:17.400 --> 00:06:19.640 temporarily suppressing the hot convective 162 00:06:19.640 --> 00:06:21.720 currents that normally transport heat from 163 00:06:21.720 --> 00:06:24.200 the Sun's interior. This makes these regions 164 00:06:24.200 --> 00:06:25.880 cooler than their surroundings, around 165 00:06:25.960 --> 00:06:28.960 6,500 degrees Fahrenheit, compared 166 00:06:28.960 --> 00:06:30.880 to the normal surface temperature of about 167 00:06:30.880 --> 00:06:33.560 10,000 degrees. That temperature difference 168 00:06:33.560 --> 00:06:35.680 is why they appear dark against the brighter 169 00:06:35.680 --> 00:06:36.120 background. 170 00:06:36.440 --> 00:06:39.160 Anna: And these magnetic fields, they're what cause 171 00:06:39.160 --> 00:06:41.480 solar flares and coronal mass ejections, 172 00:06:41.480 --> 00:06:41.800 right? 173 00:06:42.330 --> 00:06:45.090 Avery: Exactly. Large, complex sunspot groups like 174 00:06:45.090 --> 00:06:47.610 this one have tangled magnetic field lines 175 00:06:47.610 --> 00:06:49.690 that can suddenly reconnect and release 176 00:06:49.770 --> 00:06:52.410 enormous amounts of energy. This particular 177 00:06:52.490 --> 00:06:54.930 sunspot is being closely monitored because of 178 00:06:54.930 --> 00:06:57.810 its size and complexity. When these magnetic 179 00:06:57.810 --> 00:07:00.170 structures become unstable, they can unleash 180 00:07:00.170 --> 00:07:02.610 powerful solar flares and potentially hurl 181 00:07:02.610 --> 00:07:05.010 billions of tons of charged particles toward 182 00:07:05.010 --> 00:07:06.970 Earth in what's called a coronal mass 183 00:07:06.970 --> 00:07:08.570 ejection, or cme. 184 00:07:08.810 --> 00:07:10.810 Anna: Should we be concerned about potential 185 00:07:10.810 --> 00:07:11.850 impacts on Earth? 186 00:07:12.370 --> 00:07:14.370 Avery: Base weather forecasters are definitely 187 00:07:14.370 --> 00:07:16.770 keeping a close eye on it. A large CME 188 00:07:16.770 --> 00:07:19.050 directed at Earth could affect satellites, 189 00:07:19.050 --> 00:07:21.850 power grids, and radio communications and 190 00:07:21.850 --> 00:07:23.810 could produce aurora displays at lower 191 00:07:23.810 --> 00:07:26.690 latitudes than usual. However, our sun 192 00:07:26.690 --> 00:07:29.530 monitoring satellites like SoHo and SDO 193 00:07:29.530 --> 00:07:32.130 give us advance warning, typically several 194 00:07:32.130 --> 00:07:35.010 days before CME arrives. So while this 195 00:07:35.010 --> 00:07:37.290 sunspot certainly has the potential to be 196 00:07:37.290 --> 00:07:39.850 active, we have the monitoring infrastructure 197 00:07:39.850 --> 00:07:42.170 in place to track any eruptions and issue 198 00:07:42.170 --> 00:07:43.410 warnings if necessary. 199 00:07:43.790 --> 00:07:45.790 Anna: It's one of those reminders that we live 200 00:07:45.790 --> 00:07:48.190 inside the Sun's atmosphere. In a sense, 201 00:07:48.350 --> 00:07:50.510 we're constantly bathed in the solar wind. 202 00:07:50.830 --> 00:07:53.190 Avery: That's a great way to think about it. Earth's 203 00:07:53.190 --> 00:07:55.310 magnetic field shields us from most of the 204 00:07:55.310 --> 00:07:57.670 effects, but we're definitely connected to 205 00:07:57.670 --> 00:07:59.909 our star's activity. And for amateur 206 00:07:59.909 --> 00:08:02.430 astronomers, it's a rare chance to see solar 207 00:08:02.430 --> 00:08:04.750 activity on this scale with safe solar 208 00:08:04.750 --> 00:08:05.550 viewing equipment. 209 00:08:05.870 --> 00:08:08.510 Anna: All right. From solar weather to Martian 210 00:08:08.510 --> 00:08:11.200 weather. Avery, there's been an unusual 211 00:08:11.200 --> 00:08:13.840 storm on Mars. That's revealing something new 212 00:08:13.840 --> 00:08:15.080 about the Red Planet. 213 00:08:15.240 --> 00:08:18.000 Avery: Yes, and this is a particularly intriguing 214 00:08:18.000 --> 00:08:20.240 discovery because it challenges some of our 215 00:08:20.240 --> 00:08:22.200 assumptions about Martian meteorology. 216 00:08:22.840 --> 00:08:25.560 Researchers have observed an unusual storm 217 00:08:25.560 --> 00:08:27.920 system on Mars that's providing new insights 218 00:08:27.920 --> 00:08:30.520 into the planet's atmospheric dynamics and 219 00:08:30.520 --> 00:08:32.840 what lies beneath its dusty surface. 220 00:08:33.160 --> 00:08:36.160 Anna: What made this storm unusual? I mean, Mars 221 00:08:36.160 --> 00:08:37.720 is famous for its dust storms. 222 00:08:38.150 --> 00:08:40.510 Avery: True. But this storm exhibited behavior that 223 00:08:40.510 --> 00:08:42.750 didn't fit our standard models of Martian 224 00:08:42.750 --> 00:08:45.190 weather patterns. The storm's movement and 225 00:08:45.190 --> 00:08:47.350 structure suggested it was being influenced 226 00:08:47.350 --> 00:08:49.990 by subsurface features. Essentially, the 227 00:08:49.990 --> 00:08:52.590 topology and composition beneath Mars 228 00:08:52.590 --> 00:08:54.950 surface was affecting how the storm developed 229 00:08:54.950 --> 00:08:56.390 and moved across the planet. 230 00:08:56.630 --> 00:08:59.310 Anna: So, uh, the ground itself is influencing the 231 00:08:59.310 --> 00:09:00.790 weather. How does that work? 232 00:09:00.950 --> 00:09:03.470 Avery: It's similar to how mountains on Earth affect 233 00:09:03.470 --> 00:09:05.830 weather patterns. But Mars has some unique 234 00:09:05.830 --> 00:09:08.470 factors. The thin Martian atmosphere, um, 235 00:09:08.470 --> 00:09:11.220 less than 1% of Earth's atmospheric pressure, 236 00:09:11.460 --> 00:09:13.260 Means that surface features have a 237 00:09:13.260 --> 00:09:16.020 proportionately larger impact on atmospheric 238 00:09:16.020 --> 00:09:18.860 circulation. Additionally, variations in 239 00:09:18.860 --> 00:09:21.180 surface temperature Due to different rock and 240 00:09:21.180 --> 00:09:24.140 soil composition can create localized heating 241 00:09:24.140 --> 00:09:26.340 patterns that drive atmospheric motion. 242 00:09:26.420 --> 00:09:28.820 Anna: And what did the storm reveal about what's 243 00:09:28.820 --> 00:09:29.460 underground? 244 00:09:29.700 --> 00:09:31.660 Avery: The storm's behavior suggested there are 245 00:09:31.660 --> 00:09:34.180 variations in subsurface composition that 246 00:09:34.180 --> 00:09:36.710 weren't previously mapped. By tracking how 247 00:09:36.710 --> 00:09:39.150 the storm responded to these hidden features, 248 00:09:39.310 --> 00:09:41.750 Scientists could essentially use the storm as 249 00:09:41.750 --> 00:09:44.190 a probe to detect what's below the surface. 250 00:09:44.430 --> 00:09:46.630 It's a bit like how doctors use ultrasound. 251 00:09:46.630 --> 00:09:49.190 You're using one thing to indirectly sense 252 00:09:49.190 --> 00:09:49.470 another. 253 00:09:49.710 --> 00:09:51.710 Anna: That's a clever way to gather geological 254 00:09:51.789 --> 00:09:54.230 information. Are there implications for 255 00:09:54.230 --> 00:09:55.470 future Mars missions? 256 00:09:55.790 --> 00:09:57.690 Avery: Definitely. Understanding these subsurface, 257 00:09:57.690 --> 00:09:59.790 um, features is important for several 258 00:09:59.870 --> 00:10:02.390 reasons. First, they could indicate locations 259 00:10:02.390 --> 00:10:04.670 where subsurface water ice might be present. 260 00:10:05.340 --> 00:10:07.340 Second, um, they help us understand Mars's 261 00:10:07.340 --> 00:10:09.460 geological history and how the planet 262 00:10:09.460 --> 00:10:12.020 evolved. And third, for future crewed 263 00:10:12.020 --> 00:10:14.260 missions, knowing what's underground is 264 00:10:14.260 --> 00:10:16.420 essential for landing site selection and 265 00:10:16.420 --> 00:10:18.900 resource utilization. You want to land 266 00:10:18.900 --> 00:10:21.020 somewhere with access to useful materials. 267 00:10:21.099 --> 00:10:23.620 Anna: It's fascinating how atmospheric science and 268 00:10:23.620 --> 00:10:26.460 geology intersect like this one storm 269 00:10:26.460 --> 00:10:29.100 can tell you so much about an entire planet. 270 00:10:29.260 --> 00:10:31.780 Avery: Exactly. And it's another example of how 271 00:10:31.780 --> 00:10:34.460 every Mars observation opens new questions. 272 00:10:34.570 --> 00:10:37.080 And the more we learn, the more complex and 273 00:10:37.080 --> 00:10:38.640 interesting Mars becomes. 274 00:10:38.960 --> 00:10:39.520 Anna: Indeed. 275 00:10:39.920 --> 00:10:42.480 Now, speaking of complex and interesting, uh, 276 00:10:42.480 --> 00:10:44.960 let's talk about NASA's Space Launch System. 277 00:10:45.200 --> 00:10:47.720 There's been some remarkably frank discussion 278 00:10:47.720 --> 00:10:50.040 from NASA about this rocket's future, hasn't 279 00:10:50.040 --> 00:10:50.320 there? 280 00:10:50.720 --> 00:10:53.560 Avery: Yes, and it's notable precisely because 281 00:10:53.560 --> 00:10:56.520 NASA officials are rarely this candid about 282 00:10:56.520 --> 00:10:59.200 program challenges. Anna, for the first time, 283 00:10:59.200 --> 00:11:01.720 NASA is publicly acknowledging what many 284 00:11:01.720 --> 00:11:04.080 industry analysts have been saying for years. 285 00:11:04.640 --> 00:11:07.280 The Space Launch System has fundamental cost 286 00:11:07.280 --> 00:11:09.720 and sustainability issues that need to be 287 00:11:09.720 --> 00:11:10.240 addressed. 288 00:11:10.480 --> 00:11:12.760 Anna: This is the rocket that's supposed to take 289 00:11:12.760 --> 00:11:15.000 astronauts back to the moon. Part of the 290 00:11:15.000 --> 00:11:16.400 Artemis program, right? 291 00:11:16.960 --> 00:11:19.560 Avery: That's correct. The SLS is the most 292 00:11:19.560 --> 00:11:22.440 powerful rocket NASA has ever built, Designed 293 00:11:22.440 --> 00:11:25.000 specifically For deep space missions. It 294 00:11:25.000 --> 00:11:27.440 successfully launched Artemis 1 in late 295 00:11:27.440 --> 00:11:30.280 2022, sending an uncrewed Orion 296 00:11:30.280 --> 00:11:32.610 spacecraft around the moon. And it's 297 00:11:32.610 --> 00:11:35.010 scheduled to launch Artemis 2, the first 298 00:11:35.010 --> 00:11:37.970 crewed lunar mission in over 50 years. Though 299 00:11:37.970 --> 00:11:39.410 that timeline keeps shifting. 300 00:11:39.890 --> 00:11:42.850 Anna: So, uh, what's the issue? The rocket works, 301 00:11:42.850 --> 00:11:43.410 doesn't it? 302 00:11:43.730 --> 00:11:46.450 Avery: The rocket does work. When it flies, it 303 00:11:46.450 --> 00:11:49.210 performs beautifully. The problem is the 304 00:11:49.210 --> 00:11:52.170 economics. Each SLS Launch costs 305 00:11:52.170 --> 00:11:55.130 roughly $4 billion, and the system can 306 00:11:55.130 --> 00:11:57.370 only fly about once a year with current 307 00:11:57.370 --> 00:11:59.430 infrastructure. For comparison, 308 00:11:59.590 --> 00:12:02.350 SpaceX's Starship, which is also designed for 309 00:12:02.350 --> 00:12:04.990 deep space missions and has greater payload 310 00:12:04.990 --> 00:12:07.910 capacity, is projected to cost a tiny 311 00:12:07.910 --> 00:12:09.830 fraction of that per launch and could 312 00:12:09.830 --> 00:12:12.070 potentially fly dozens of times per year. 313 00:12:12.630 --> 00:12:15.550 Anna: 4 billion per launch. That's hard 314 00:12:15.550 --> 00:12:18.110 to justify, especially when alternatives 315 00:12:18.110 --> 00:12:18.470 exist. 316 00:12:18.950 --> 00:12:21.270 Avery: Exactly. And that's what makes these recent 317 00:12:21.270 --> 00:12:22.950 NASA statements so significant. 318 00:12:23.670 --> 00:12:25.830 Administrators are openly discussing the 319 00:12:25.830 --> 00:12:28.770 elephant in the room that maintaining SLS in 320 00:12:28.770 --> 00:12:31.330 its current form may not be sustainable for a 321 00:12:31.330 --> 00:12:33.850 long term lunar or Mars exploration program. 322 00:12:34.330 --> 00:12:36.250 They're acknowledging that the program needs 323 00:12:36.250 --> 00:12:38.890 to either dramatically reduce costs or 324 00:12:38.890 --> 00:12:40.690 potentially transition to commercial 325 00:12:40.690 --> 00:12:41.450 alternatives. 326 00:12:41.850 --> 00:12:44.650 Anna: This must be a difficult position for NASA. 327 00:12:44.730 --> 00:12:47.450 The SLS represents decades of development 328 00:12:47.610 --> 00:12:49.050 and enormous investment. 329 00:12:49.770 --> 00:12:52.730 Avery: It absolutely is. There are also political 330 00:12:52.810 --> 00:12:55.770 considerations. The SLS program supports 331 00:12:55.770 --> 00:12:58.570 jobs across multiple states and has strong 332 00:12:58.570 --> 00:13:01.170 congressional backing. But NASA is facing 333 00:13:01.170 --> 00:13:03.330 budgetary pressure and needs to make 334 00:13:03.330 --> 00:13:05.850 realistic plans for sustainable exploration. 335 00:13:06.330 --> 00:13:08.650 The acknowledgment that SLS's costs are 336 00:13:08.650 --> 00:13:11.010 problematic is a significant shift towards 337 00:13:11.010 --> 00:13:13.370 having honest conversations about the future 338 00:13:13.370 --> 00:13:14.890 of deep space exploration. 339 00:13:15.370 --> 00:13:17.970 Anna: What are the alternatives? Would NASA switch 340 00:13:17.970 --> 00:13:20.090 to something like Starship entirely? 341 00:13:20.780 --> 00:13:22.940 Avery: That's one option being discussed, though 342 00:13:22.940 --> 00:13:25.420 it's complicated. NASA has already 343 00:13:25.420 --> 00:13:27.780 contracted with SpaceX to provide a lunar 344 00:13:27.780 --> 00:13:29.740 lander version of Starship for Artemis 345 00:13:29.740 --> 00:13:31.900 missions. So there's already commercial 346 00:13:31.900 --> 00:13:34.540 partnership in place. Some proposals suggest 347 00:13:34.620 --> 00:13:37.180 using commercial heavy lift rockets for cargo 348 00:13:37.260 --> 00:13:40.060 and potentially even crew, while others 349 00:13:40.060 --> 00:13:42.820 advocate for a hybrid approach. The challenge 350 00:13:42.820 --> 00:13:45.100 is that any major change would require 351 00:13:45.100 --> 00:13:47.180 congressional approval and significant 352 00:13:47.420 --> 00:13:49.340 replanning of Artemis architecture. 353 00:13:49.830 --> 00:13:52.150 Anna: It sounds like we're at an inflection point 354 00:13:52.150 --> 00:13:54.070 for NASA's deep space ambitions. 355 00:13:54.630 --> 00:13:57.270 Avery: We really are. This is one of those moments 356 00:13:57.270 --> 00:13:59.750 where honesty about challenges is the first 357 00:13:59.750 --> 00:14:02.430 step towards finding solutions. The fact that 358 00:14:02.430 --> 00:14:04.470 NASA is willing to have this conversation 359 00:14:04.470 --> 00:14:07.110 publicly suggests they're serious about 360 00:14:07.110 --> 00:14:09.950 finding a sustainable path forward, even if 361 00:14:09.950 --> 00:14:12.190 it means difficult decisions about programs 362 00:14:12.190 --> 00:14:14.070 that have tremendous legacy and political 363 00:14:14.150 --> 00:14:14.550 support. 364 00:14:14.710 --> 00:14:16.790 Anna: Well, we'll certainly be watching how this 365 00:14:16.790 --> 00:14:17.350 develops. 366 00:14:18.040 --> 00:14:20.440 Now for our final story, let's venture into 367 00:14:20.440 --> 00:14:23.360 the realm of stellar evolution. Avery 368 00:14:23.360 --> 00:14:26.080 red giant stars are apparently destroying 369 00:14:26.080 --> 00:14:27.800 their own planetary systems. 370 00:14:28.040 --> 00:14:30.720 Avery: They are Anna. And this research gives us a 371 00:14:30.720 --> 00:14:32.800 rather apocalyptic preview of what will 372 00:14:32.800 --> 00:14:35.240 happen to our own solar system in about 5 373 00:14:35.240 --> 00:14:38.160 billion years. Astronomers have observed how 374 00:14:38.160 --> 00:14:40.680 red giant stars, stars in their late 375 00:14:40.680 --> 00:14:43.680 evolutionary stages, systematically destroy 376 00:14:43.680 --> 00:14:46.000 gas giant planets that orbit too close to 377 00:14:46.000 --> 00:14:46.280 them. 378 00:14:46.770 --> 00:14:48.930 Anna: This is what our sun will eventually become, 379 00:14:49.010 --> 00:14:50.450 right? A red giant. 380 00:14:50.850 --> 00:14:53.770 Avery: Exactly. When stars like our sun exhaust the 381 00:14:53.770 --> 00:14:56.250 hydrogen fuel in their cores, they begin 382 00:14:56.250 --> 00:14:58.530 fusing helium and expand dramatically. 383 00:14:59.010 --> 00:15:01.530 Our sun will eventually swell to perhaps a 384 00:15:01.530 --> 00:15:04.130 hundred times its current diameter, likely 385 00:15:04.130 --> 00:15:06.810 engulfing Mercury, Venus, and possibly 386 00:15:06.810 --> 00:15:09.490 Earth. But this research focuses on what 387 00:15:09.490 --> 00:15:11.290 happens to planets that, uh, survive the 388 00:15:11.290 --> 00:15:14.280 initial expansion, particularly gas giants, 389 00:15:14.280 --> 00:15:16.400 uh, at distances similar to Jupiter and 390 00:15:16.400 --> 00:15:17.720 Saturn's current orbits. 391 00:15:18.200 --> 00:15:20.520 Anna: Though these planets survive the star's 392 00:15:20.520 --> 00:15:22.760 expansion, but not what comes after. 393 00:15:23.160 --> 00:15:25.840 Avery: Precisely. As the star becomes a red 394 00:15:25.840 --> 00:15:28.680 giant, several destructive processes occur. 395 00:15:29.240 --> 00:15:32.040 First, the star becomes much more luminous. 396 00:15:32.360 --> 00:15:35.000 Our sun will eventually be about 2,000 397 00:15:35.080 --> 00:15:37.560 times brighter than it is now. This 398 00:15:37.560 --> 00:15:40.360 intense radiation heats the atmospheres of 399 00:15:40.360 --> 00:15:43.360 gas giant planets, causing them to expand 400 00:15:43.360 --> 00:15:46.260 and potentially evaporate. Second, 401 00:15:46.660 --> 00:15:49.420 red giant stars have powerful stellar 402 00:15:49.420 --> 00:15:51.620 winds that can strip away planetary 403 00:15:51.620 --> 00:15:54.340 atmospheres. And third, the star's 404 00:15:54.340 --> 00:15:57.060 expansion causes tidal forces that can 405 00:15:57.060 --> 00:15:58.740 alter planetary orbits. 406 00:15:58.900 --> 00:16:01.100 Anna: That sounds like a recipe for planetary 407 00:16:01.100 --> 00:16:03.860 destruction. What exactly did the researchers 408 00:16:03.860 --> 00:16:04.340 observe? 409 00:16:04.500 --> 00:16:07.340 Avery: They studied multiple red giant star systems 410 00:16:07.340 --> 00:16:09.980 and found evidence of gas giant planets in 411 00:16:09.980 --> 00:16:12.700 the process of being destroyed. In some 412 00:16:12.700 --> 00:16:15.420 cases, they detected the spectral signatures 413 00:16:15.420 --> 00:16:18.180 of planetary material being stripped away 414 00:16:18.180 --> 00:16:21.020 and falling into their host star. In others, 415 00:16:21.100 --> 00:16:23.780 they found gas giants with highly eroded 416 00:16:23.780 --> 00:16:26.340 atmospheres, clearly showing the effects of 417 00:16:26.340 --> 00:16:28.900 their star's evolution. It's like watching 418 00:16:28.900 --> 00:16:31.300 different stages of the same destructive 419 00:16:31.300 --> 00:16:31.660 process. 420 00:16:32.060 --> 00:16:34.220 Anna: This presumably has implications for our 421 00:16:34.220 --> 00:16:36.700 understanding of how planetary systems evolve 422 00:16:36.700 --> 00:16:37.260 over time. 423 00:16:37.420 --> 00:16:40.300 Avery: Absolutely. One of the key findings is 424 00:16:40.300 --> 00:16:42.540 that the habitable zone, the region where 425 00:16:42.540 --> 00:16:45.500 liquid water could exist, moves outward 426 00:16:45.500 --> 00:16:48.380 as a star becomes a red giant. Moons 427 00:16:48.380 --> 00:16:51.340 of Jupiter or Saturn, currently frozen ice 428 00:16:51.340 --> 00:16:54.260 worlds, might temporarily become habitable 429 00:16:54.260 --> 00:16:56.860 as our sun swells. But this research 430 00:16:57.020 --> 00:16:59.740 shows that even if these worlds briefly enter 431 00:16:59.740 --> 00:17:02.660 the habitable zone, the gas giants they orbit 432 00:17:02.660 --> 00:17:05.220 are being actively destroyed by the dying 433 00:17:05.220 --> 00:17:07.989 star. It's a very dynamic and 434 00:17:07.989 --> 00:17:09.709 ultimately doomed situation. 435 00:17:09.789 --> 00:17:12.229 Anna: It really puts our solar system's long term 436 00:17:12.229 --> 00:17:13.309 future in perspective. 437 00:17:13.389 --> 00:17:16.069 Avery: It does, Though I should emphasize we have 438 00:17:16.069 --> 00:17:18.669 about 5 billion years before any of this 439 00:17:18.669 --> 00:17:21.109 happens, so there's no immediate cause for 440 00:17:21.109 --> 00:17:23.749 concern. But it does remind us that solar 441 00:17:23.749 --> 00:17:25.589 systems, like everything else in the 442 00:17:25.589 --> 00:17:28.509 universe, have life cycles. Understanding 443 00:17:28.509 --> 00:17:30.829 these cycles helps us interpret what we see 444 00:17:30.829 --> 00:17:33.309 around other stars and appreciate that the 445 00:17:33.309 --> 00:17:35.949 stable, long lived solar system we enjoy 446 00:17:36.189 --> 00:17:38.730 is a temporary phase in cosmic terms. 447 00:17:38.890 --> 00:17:41.490 Anna: A sobering but fascinating look at stellar 448 00:17:41.490 --> 00:17:43.410 evolution. It's one thing to know 449 00:17:43.410 --> 00:17:45.370 intellectually that the sun will eventually 450 00:17:45.370 --> 00:17:48.170 die, but quite another to see the detailed 451 00:17:48.170 --> 00:17:49.930 process of what happens to the planets. 452 00:17:50.170 --> 00:17:53.130 Avery: Exactly. And who knows, in 5 billion 453 00:17:53.130 --> 00:17:55.850 years, humanity's descendants, if they exist, 454 00:17:56.090 --> 00:17:58.770 will likely have long since relocated to 455 00:17:58.770 --> 00:18:01.450 other star systems. Understanding how stars 456 00:18:01.450 --> 00:18:03.970 age and die is actually crucial for picking 457 00:18:03.970 --> 00:18:05.930 good long term neighborhoods out in the 458 00:18:05.930 --> 00:18:06.410 galaxy. 459 00:18:06.410 --> 00:18:08.570 Anna: That's a nice optimistic note to end on. 460 00:18:09.020 --> 00:18:10.700 Well, that's all we have for you today on 461 00:18:10.700 --> 00:18:11.660 Astronomy Daily. 462 00:18:11.740 --> 00:18:13.740 Avery: And remember to check out our website at, uh, 463 00:18:13.740 --> 00:18:16.620 astronomydaily IO for more space 464 00:18:16.620 --> 00:18:18.860 news and to join our community discussions. 465 00:18:19.180 --> 00:18:20.700 You can also find us on social 466 00:18:20.700 --> 00:18:22.780 media@astrodaily.pod. 467 00:18:22.780 --> 00:18:24.939 Anna: Thanks for listening and keep looking up. 468 00:18:36.220 --> 00:18:36.860 Avery: The stories. 469 00:18:44.700 --> 00:18:45.340 We told.