WEBVTT 0 00:00:00.480 --> 00:00:03.120 Avery: Welcome back to Astronomy Daily, the 1 00:00:03.120 --> 00:00:05.760 podcast that brings the cosmos down to 2 00:00:05.760 --> 00:00:07.840 Earth. I'm your host, Avery. 3 00:00:08.000 --> 00:00:10.800 Anna: And I'm your other host, Anna. Uh, it's great 4 00:00:10.800 --> 00:00:13.240 to have you with us. We have an absolutely 5 00:00:13.240 --> 00:00:15.560 packed show for you today with news that 6 00:00:15.560 --> 00:00:16.880 spans our solar system. 7 00:00:17.280 --> 00:00:19.680 Avery: We are starting in the outer solar system 8 00:00:19.760 --> 00:00:22.560 with some incredible new findings from not 9 00:00:22.560 --> 00:00:25.040 one, but two of Saturn's moons. 10 00:00:25.440 --> 00:00:27.990 First up, Enceladus, which is looking 11 00:00:28.150 --> 00:00:30.790 more and more like a prime candidate for 12 00:00:30.790 --> 00:00:32.710 hosting extraterrestrial life. 13 00:00:33.110 --> 00:00:35.390 Anna: Then we'll stay in the same neighborhood to 14 00:00:35.390 --> 00:00:38.190 visit Titan, Saturn's largest moon, where 15 00:00:38.190 --> 00:00:40.910 its entire atmosphere appears to be doing 16 00:00:40.910 --> 00:00:43.470 something very strange, something scientists 17 00:00:43.470 --> 00:00:45.590 are comparing to a, uh, gyroscope. 18 00:00:45.990 --> 00:00:48.710 Avery: From there, we're taking a big leap inwards, 19 00:00:49.030 --> 00:00:51.510 all the way to our planetary neighbor, 20 00:00:51.510 --> 00:00:54.430 Venus. You might think you know Venus, but 21 00:00:54.430 --> 00:00:57.430 a fresh look at some very old data has 22 00:00:57.430 --> 00:00:59.570 turned our understanding of its clouds 23 00:00:59.570 --> 00:01:00.930 completely on its head. 24 00:01:01.090 --> 00:01:03.250 Anna: And to wrap things up, we'll bring it all 25 00:01:03.250 --> 00:01:05.490 back home. A new survey from Australia 26 00:01:05.890 --> 00:01:08.850 reveals a fascinating and perhaps slightly 27 00:01:08.850 --> 00:01:11.490 worrying gap between how much people support 28 00:01:11.490 --> 00:01:14.290 the space industry and how much they actually 29 00:01:14.370 --> 00:01:15.250 know about it. 30 00:01:15.330 --> 00:01:18.210 Avery: It's a journey from potential alien oceans 31 00:01:18.290 --> 00:01:21.010 to public opinion polls, so let's not 32 00:01:21.010 --> 00:01:22.050 waste any more time. 33 00:01:22.450 --> 00:01:24.610 Anna, uh, why don't you start us off with the 34 00:01:24.610 --> 00:01:26.370 exciting news from Enceladus. 35 00:01:26.650 --> 00:01:29.250 Anna: My pleasure, Avery. This story is a 36 00:01:29.250 --> 00:01:31.850 beautiful example of a mission that just 37 00:01:31.850 --> 00:01:34.770 keeps on giving. The Cassini spacecraft 38 00:01:34.770 --> 00:01:37.570 gave us two decades of incredible insights 39 00:01:37.570 --> 00:01:40.090 into Saturn. And even years after the mission 40 00:01:40.090 --> 00:01:42.890 ended, scientists are still mining its data 41 00:01:42.890 --> 00:01:43.370 for gold. 42 00:01:43.690 --> 00:01:46.090 Avery: And it seems they've struck a new vein. 43 00:01:46.410 --> 00:01:49.210 This is about those amazing water plumes, 44 00:01:49.210 --> 00:01:52.010 right? The ones Cassini actually flew 45 00:01:52.010 --> 00:01:52.330 through? 46 00:01:52.760 --> 00:01:55.560 Anna: That's the one. Almost 20 years ago, 47 00:01:55.560 --> 00:01:57.800 Cassini flew through plumes of water 48 00:01:58.200 --> 00:02:00.720 bursting from cracks in the icy surface of 49 00:02:00.720 --> 00:02:03.680 Enceladus. Now, a new analysis of 50 00:02:03.680 --> 00:02:06.600 that fly through data has confirmed what many 51 00:02:06.600 --> 00:02:09.440 had hoped, that complex chemical reactions 52 00:02:09.440 --> 00:02:11.800 are happening within the Moon's hidden 53 00:02:12.040 --> 00:02:13.560 subsurface ocean. 54 00:02:13.800 --> 00:02:16.440 Avery: That sounds huge. When we talk about 55 00:02:16.520 --> 00:02:18.800 searching for life, we're always looking for 56 00:02:18.800 --> 00:02:21.530 certain key ingredients. What does this new 57 00:02:21.530 --> 00:02:22.330 finding tell us? 58 00:02:22.490 --> 00:02:25.450 Anna: Well, it essentially affirms that Enceladus 59 00:02:25.450 --> 00:02:28.010 has all three of the major conditions 60 00:02:28.250 --> 00:02:31.210 necessary for a habitable environment, at 61 00:02:31.210 --> 00:02:33.970 least as we understand it. You need liquid 62 00:02:33.970 --> 00:02:36.330 water, which we know the Moon has, in its 63 00:02:36.330 --> 00:02:39.090 subsurface ocean. You need a source of 64 00:02:39.090 --> 00:02:42.050 energy, likely from hydrothermal vents on the 65 00:02:42.050 --> 00:02:44.730 ocean floor. And you need a specific 66 00:02:44.810 --> 00:02:47.490 set of chemical elements, the building blocks 67 00:02:47.490 --> 00:02:47.930 of life. 68 00:02:48.370 --> 00:02:51.250 Avery: And this new analysis adds more to that 69 00:02:51.250 --> 00:02:54.050 third category. The Chemical building blocks. 70 00:02:54.050 --> 00:02:56.450 Anna: Exactly. They found organic 71 00:02:56.450 --> 00:02:58.930 molecules, some new ones they hadn't detected 72 00:02:58.930 --> 00:03:01.650 before in the fresh ice grains that were 73 00:03:01.650 --> 00:03:04.610 ejected directly from the ocean. This 74 00:03:04.610 --> 00:03:07.170 included molecular fragments that potentially 75 00:03:07.170 --> 00:03:09.890 contain nitrogen and oxygen, which are 76 00:03:09.890 --> 00:03:12.130 crucial for life as we know it. 77 00:03:12.450 --> 00:03:15.290 Avery: So this is direct evidence of complex 78 00:03:15.290 --> 00:03:18.050 chemistry happening right now in that ocean. 79 00:03:18.070 --> 00:03:20.660 And Frank Postberg, one of the co authors, 80 00:03:20.660 --> 00:03:22.780 made a really important point about this, 81 00:03:22.780 --> 00:03:23.220 didn't he? 82 00:03:23.220 --> 00:03:26.180 Anna: He did. He emphasized that these molecules 83 00:03:26.180 --> 00:03:28.780 were found in freshly ejected material. 84 00:03:29.100 --> 00:03:32.020 This proves that the complex organics Cassini 85 00:03:32.020 --> 00:03:35.020 previously detected in Saturn's E ring 86 00:03:35.180 --> 00:03:37.220 aren't just the result of being zapped by 87 00:03:37.220 --> 00:03:40.020 radiation in space for a long time. They are 88 00:03:40.020 --> 00:03:42.620 being actively produced or are readily 89 00:03:42.620 --> 00:03:44.460 available right there in the ocean. 90 00:03:45.070 --> 00:03:47.110 Avery: So it's an active, chemically rich 91 00:03:47.110 --> 00:03:49.750 environment. And I believe another scientist 92 00:03:49.750 --> 00:03:52.630 on the paper, Nozair Kawasha, added that 93 00:03:52.630 --> 00:03:55.070 there are many possible chemical pathways 94 00:03:55.070 --> 00:03:57.270 that could lead from these simple organic 95 00:03:57.270 --> 00:03:59.150 molecules to more complex 96 00:03:59.470 --> 00:04:01.470 biologically relevant compounds. 97 00:04:01.470 --> 00:04:04.310 Anna: That's right. It significantly enhances the 98 00:04:04.310 --> 00:04:06.590 likelihood that the moon is habitable. 99 00:04:07.070 --> 00:04:09.830 We have to be clear, this is not evidence of 100 00:04:09.830 --> 00:04:12.350 life itself. But it is perhaps the 101 00:04:12.350 --> 00:04:14.510 strongest evidence yet that an environment 102 00:04:14.670 --> 00:04:16.970 that could support life exists, exists 103 00:04:17.290 --> 00:04:19.930 right now in our own solar system. 104 00:04:20.250 --> 00:04:22.330 Avery: Well, let's not leave the Saturn system just 105 00:04:22.330 --> 00:04:25.170 yet, because its biggest moon, Titan, is also 106 00:04:25.170 --> 00:04:27.370 making headlines with some very unusual 107 00:04:27.370 --> 00:04:27.850 behavior. 108 00:04:28.330 --> 00:04:31.210 Anna: That's right. If Enceladus is all about its 109 00:04:31.210 --> 00:04:34.130 hidden ocean, Titan is famous for its 110 00:04:34.130 --> 00:04:37.090 thick, hazy atmosphere. It's the only 111 00:04:37.090 --> 00:04:39.770 moon in our solar system with a substantial 112 00:04:39.770 --> 00:04:42.490 atmosphere, denser even than Earth. 113 00:04:43.230 --> 00:04:45.020 Avery: Um, and we've always known it's a weird place 114 00:04:45.020 --> 00:04:47.980 with its methane lakes and rivers. But now it 115 00:04:47.980 --> 00:04:49.820 seems the atmosphere itself is acting 116 00:04:49.820 --> 00:04:50.380 strangely. 117 00:04:50.780 --> 00:04:53.260 Anna: Researchers at the University of Bristol have 118 00:04:53.260 --> 00:04:56.180 uncovered that Titan's atmosphere doesn't 119 00:04:56.180 --> 00:04:59.180 rotate in step with its surface. The new 120 00:04:59.180 --> 00:05:01.380 discovery is that the entire atmospheric 121 00:05:01.380 --> 00:05:03.980 system seems to be tilted off axis, 122 00:05:04.300 --> 00:05:07.220 and it wobbles or oscillates almost 123 00:05:07.220 --> 00:05:09.660 like a spinning top or a gyroscope. 124 00:05:10.270 --> 00:05:13.030 Avery: The whole atmosphere is wobbling. How m is 125 00:05:13.030 --> 00:05:13.470 that possible? 126 00:05:13.950 --> 00:05:16.350 Anna: The prevailing theory is that some major 127 00:05:16.350 --> 00:05:18.950 event in Titan's past could have knocked the 128 00:05:18.950 --> 00:05:21.310 atmosphere off its original spin axis, 129 00:05:21.470 --> 00:05:24.310 causing it to wobble ever since. What's 130 00:05:24.310 --> 00:05:27.070 even stranger is that the size of this wobble 131 00:05:27.230 --> 00:05:30.190 actually changes with Titan's seasons. 132 00:05:30.910 --> 00:05:32.550 Avery: That has to be a critical piece of 133 00:05:32.550 --> 00:05:34.670 information for NASA's next big mission to 134 00:05:34.670 --> 00:05:35.630 the outer solar system. 135 00:05:36.160 --> 00:05:38.840 Anna: Absolutely. We're talking about the Dragonfly 136 00:05:38.840 --> 00:05:41.280 mission, the car sized drone like 137 00:05:41.280 --> 00:05:43.480 rotorcraft that's scheduled to arrive at 138 00:05:43.480 --> 00:05:46.160 titan in the2030s. Its whole 139 00:05:46.160 --> 00:05:49.040 mission is to fly through Titan's atmosphere. 140 00:05:49.280 --> 00:05:51.200 Avery: And if you're trying to land a multi billion 141 00:05:51.200 --> 00:05:53.440 dollar nuclear powered drone on a distant 142 00:05:53.440 --> 00:05:55.920 moon, you'd probably like to know if the 143 00:05:55.920 --> 00:05:58.160 entire atmosphere you're flying through is 144 00:05:58.160 --> 00:05:58.880 wobbling around. 145 00:05:59.360 --> 00:06:02.230 Anna: To put it mildly, yes. Understanding 146 00:06:02.230 --> 00:06:04.870 how the atmosphere behaves is absolutely 147 00:06:04.870 --> 00:06:06.630 crucial for calculating the landing 148 00:06:06.630 --> 00:06:09.590 trajectory. This discovery is a vital 149 00:06:09.590 --> 00:06:10.830 new piece of that puzzle. 150 00:06:11.070 --> 00:06:13.190 Avery: Okay, from the cold hazy reaches of the 151 00:06:13.190 --> 00:06:15.950 Saturn system, let's head sunward to a 152 00:06:15.950 --> 00:06:18.430 place that's anything but cold. Venus. 153 00:06:18.750 --> 00:06:20.670 And uh, for as long as I can remember, the 154 00:06:20.670 --> 00:06:23.510 defining feature of Venus has been its clouds 155 00:06:23.510 --> 00:06:24.750 of sulfuric acid. 156 00:06:25.390 --> 00:06:27.470 Anna: That has certainly been the dominant picture. 157 00:06:27.630 --> 00:06:30.070 But a new paper is challenging that in a 158 00:06:30.070 --> 00:06:32.270 fundamental way. A team of researchers 159 00:06:32.270 --> 00:06:34.530 decided to re, analyze, analyze data from 160 00:06:34.530 --> 00:06:37.170 NASA's Pioneer mission to Venus from the 161 00:06:37.170 --> 00:06:37.690 70s. 162 00:06:38.410 --> 00:06:41.090 Avery: I love these stories where old data reveals 163 00:06:41.090 --> 00:06:42.810 new secrets. What did they find? 164 00:06:43.050 --> 00:06:45.850 Anna: Pioneer analyzed aerosols in the clouds by 165 00:06:45.850 --> 00:06:47.850 seeing at what temperatures they burnt off. 166 00:06:48.090 --> 00:06:50.530 The researchers applied modern techniques to 167 00:06:50.530 --> 00:06:53.410 this old data and noticed massive spikes in 168 00:06:53.410 --> 00:06:53.770 water. 169 00:06:54.330 --> 00:06:56.530 Avery: So it's not a water cloud in the way we think 170 00:06:56.530 --> 00:06:59.010 of one on Earth, but water is a huge 171 00:06:59.010 --> 00:07:01.670 component of what it's making up the clouds. 172 00:07:01.750 --> 00:07:04.750 Anna: A, uh, huge component. It seems the water is 173 00:07:04.750 --> 00:07:07.070 locked up inside other minerals as 174 00:07:07.070 --> 00:07:09.390 hydrates. When they did the math, they found 175 00:07:09.390 --> 00:07:11.350 that this hydrated water made up the bulk of 176 00:07:11.350 --> 00:07:13.750 the aerosols, measured a, ah, staggering 177 00:07:13.910 --> 00:07:14.870 62%. 178 00:07:15.670 --> 00:07:17.990 Avery: This has enormous implications for one of the 179 00:07:17.990 --> 00:07:20.790 most exciting ideas in planetary science. The 180 00:07:20.790 --> 00:07:23.350 search for life in the clouds of Venus. 181 00:07:23.510 --> 00:07:26.070 Anna: It really does. One of the primary 182 00:07:26.070 --> 00:07:28.910 arguments against that possibility has always 183 00:07:28.910 --> 00:07:31.270 been the extreme lack of available water. 184 00:07:31.890 --> 00:07:34.530 But if water is actually far more abundant 185 00:07:34.770 --> 00:07:37.490 just chemically bound up, it completely 186 00:07:37.490 --> 00:07:40.490 changes the equation. It reopens the door to 187 00:07:40.490 --> 00:07:41.170 that possibility. 188 00:07:41.970 --> 00:07:44.530 And for our last story today, we're coming 189 00:07:44.530 --> 00:07:47.130 back to Earth. A new report has been released 190 00:07:47.130 --> 00:07:49.410 based on a survey of Australian opinions 191 00:07:49.410 --> 00:07:51.690 about space. And it reveals a really 192 00:07:51.690 --> 00:07:52.770 interesting picture. 193 00:07:53.170 --> 00:07:55.290 Avery: Let me guess, people love watching rocket 194 00:07:55.290 --> 00:07:56.850 launches but don't think about it much. 195 00:07:56.850 --> 00:07:59.610 Anna: Otherwise, that's a pretty good summary. The 196 00:07:59.610 --> 00:08:01.930 report shows a clear disconnect between the 197 00:08:01.930 --> 00:08:04.450 public's interest and their knowledge. People 198 00:08:04.450 --> 00:08:06.370 are three times more likely to want to 199 00:08:06.370 --> 00:08:09.010 increase spending on space, but awareness of 200 00:08:09.010 --> 00:08:11.810 what the sector actually does remains low. 201 00:08:12.370 --> 00:08:14.930 Avery: That's a key point. Things like using gps, 202 00:08:15.330 --> 00:08:17.210 checking the weather, or even making a credit 203 00:08:17.210 --> 00:08:19.850 card transaction often rely on data from 204 00:08:19.850 --> 00:08:21.370 satellites. It's this invisible 205 00:08:21.370 --> 00:08:23.570 infrastructure we take for granted. 206 00:08:24.240 --> 00:08:27.040 Anna: Precisely. The survey also found people 207 00:08:27.040 --> 00:08:29.800 want to see Australia pull its own weight and 208 00:08:29.800 --> 00:08:32.800 build its own space capabilities. And another 209 00:08:32.880 --> 00:08:35.520 point that came through very strongly was 210 00:08:35.520 --> 00:08:38.360 sustainability. Two thirds of respondents 211 00:08:38.360 --> 00:08:41.000 think it's important to invest in sustainable 212 00:08:41.000 --> 00:08:41.920 space practices. 213 00:08:42.640 --> 00:08:44.880 Avery: So the big takeaway is about communication. 214 00:08:45.280 --> 00:08:48.200 Anna: Exactly. The report concludes that there have 215 00:08:48.200 --> 00:08:51.040 to be real, tangible links made between this 216 00:08:51.040 --> 00:08:53.840 vital sector and the everyday lives of 217 00:08:53.840 --> 00:08:56.450 Australians, showing them how investments in 218 00:08:56.450 --> 00:08:59.250 space pay dividends right here on the ground. 219 00:08:59.890 --> 00:09:02.450 Avery: And that just about does it for us. Today we 220 00:09:02.450 --> 00:09:04.610 explored the life giving potential of, uh, 221 00:09:04.610 --> 00:09:07.370 Enceladus Ocean and the bizarre 222 00:09:07.370 --> 00:09:09.170 wobbling atmosphere of Titan. 223 00:09:09.730 --> 00:09:12.130 Anna: We rewrote the textbooks on the clouds of 224 00:09:12.130 --> 00:09:15.130 Venus and we took the pulse of public opinion 225 00:09:15.130 --> 00:09:17.890 on the importance of space right here on 226 00:09:17.890 --> 00:09:18.290 Earth. 227 00:09:18.770 --> 00:09:20.970 Avery: It's a constant reminder that there is always 228 00:09:20.970 --> 00:09:23.370 something new to discover. Thank you all so 229 00:09:23.370 --> 00:09:25.190 much for tuning in. I'm, uh, Avery. Thanks 230 00:09:25.190 --> 00:09:25.250 for. 231 00:09:25.640 --> 00:09:27.960 Anna: And I'm Anna. You've been listening to 232 00:09:27.960 --> 00:09:30.720 Astronomy Daily. For even more space 233 00:09:30.720 --> 00:09:33.520 and astronomy news, be sure to visit our 234 00:09:33.520 --> 00:09:36.200 website where we have a continuously updating 235 00:09:36.200 --> 00:09:38.160 newsfeed. You'll find us at 236 00:09:38.160 --> 00:09:41.080 astronomydaily IO. We'll 237 00:09:41.080 --> 00:09:43.240 be back tomorrow with all the latest news 238 00:09:43.240 --> 00:09:45.920 from our universe. Until then, keep looking 239 00:09:45.920 --> 00:09:46.280 up.