WEBVTT 0 00:00:00.320 --> 00:00:03.200 Anna: Welcome to Astronomy Daily, the podcast 1 00:00:03.200 --> 00:00:05.880 where we chat about the coolest space and 2 00:00:05.880 --> 00:00:08.640 astronomy news we can source. I'm Anna, 3 00:00:08.640 --> 00:00:11.200 um, and with me is my co host, Avery. 4 00:00:11.520 --> 00:00:14.160 Hey Avery, it's January 8, 5 00:00:14.320 --> 00:00:16.399 2026. How's your week going? 6 00:00:16.640 --> 00:00:19.120 Avery: Hey Anna. And hello to all our listeners. 7 00:00:19.120 --> 00:00:22.040 It's been fantastic. Clear nights for 8 00:00:22.040 --> 00:00:25.000 some stargazing. We've got a stellar lineup 9 00:00:25.000 --> 00:00:27.600 today. Mysteries solved on a famous star. 10 00:00:27.840 --> 00:00:30.320 A decades long supernova video, 11 00:00:30.800 --> 00:00:33.580 a cens nearby stars for life, 12 00:00:33.980 --> 00:00:36.900 lunar events to watch, a dramatic but 13 00:00:36.900 --> 00:00:39.780 low risk orbital scenario, and fresh 14 00:00:39.780 --> 00:00:42.500 insights on asteroid mining. Plenty to 15 00:00:42.500 --> 00:00:43.900 unpack. Let's get started. 16 00:00:44.380 --> 00:00:46.860 Anna: Leading off with big news from Orion, 17 00:00:47.100 --> 00:00:49.900 astronomers have finally cracked Betelgeuse's 18 00:00:49.900 --> 00:00:52.420 biggest mystery. The cause of its weird 19 00:00:52.420 --> 00:00:54.820 brightness swings and that dramatic great 20 00:00:54.820 --> 00:00:56.620 dimming back in 2020. 21 00:00:57.020 --> 00:00:59.700 Avery: Yeah, this red supergiant, one of the 22 00:00:59.700 --> 00:01:02.580 brightest stars in the sky and about 650 23 00:01:02.580 --> 00:01:05.240 light years, has been puzzling folks 24 00:01:05.240 --> 00:01:08.200 forever. With its pulsations, it has a short 25 00:01:08.280 --> 00:01:11.160 400 day cycle from internal throbbing. 26 00:01:11.240 --> 00:01:14.080 But there's this longer 2100 day 27 00:01:14.080 --> 00:01:16.840 variation that stumped everyone. Theories 28 00:01:16.840 --> 00:01:19.560 range from giant convection cells to dust 29 00:01:19.560 --> 00:01:21.880 clouds or even a companion star. 30 00:01:22.360 --> 00:01:25.000 Anna: Turns out it is a hidden companion. 31 00:01:25.320 --> 00:01:27.560 Researchers from the Centre for Astrophysics 32 00:01:27.560 --> 00:01:30.080 at Harvard and Smithsonian, led by Andrea 33 00:01:30.080 --> 00:01:33.000 Dupre, used nearly eight years of Hubble 34 00:01:33.000 --> 00:01:35.160 data plus ground telescopes to 35 00:01:35.780 --> 00:01:38.540 direct evidence. The companion, playfully 36 00:01:38.540 --> 00:01:41.500 called Siwarha, orbits every six years or 37 00:01:41.500 --> 00:01:44.140 so, ploughing through Betelgeuse's massive 38 00:01:44.140 --> 00:01:46.900 extended atmosphere. Like a boat cutting 39 00:01:46.900 --> 00:01:49.540 through water, leaving a dense wake of gas. 40 00:01:49.940 --> 00:01:52.460 Avery: That wake disrupts the star's light and 41 00:01:52.460 --> 00:01:54.940 spectrum, causing the dimming and patterns we 42 00:01:54.940 --> 00:01:57.940 see. Dupree described it perfectly. It's a 43 00:01:57.940 --> 00:02:00.180 bit like a boat moving through water. The 44 00:02:00.180 --> 00:02:02.540 companion star creates a ripple effect in 45 00:02:02.540 --> 00:02:04.900 Betelgeuse's atmosphere that we can actually 46 00:02:04.980 --> 00:02:07.610 see. In the data they caught the wake form 47 00:02:07.680 --> 00:02:09.680 forming right after the companion passes in 48 00:02:09.680 --> 00:02:10.000 front. 49 00:02:10.480 --> 00:02:13.440 Anna: This explains the 2020 sneeze too. 50 00:02:13.760 --> 00:02:16.640 Dust and gas from that interaction. Huge 51 00:02:16.640 --> 00:02:19.400 implications. It shows how companions can 52 00:02:19.400 --> 00:02:22.320 reshape massive stars. Evolution, mass 53 00:02:22.320 --> 00:02:24.560 loss and eventual supernovae. 54 00:02:24.720 --> 00:02:27.440 Betelgeuse is eclipsing Siwarha right now, 55 00:02:27.440 --> 00:02:30.320 but they'll watch for it emerging in 2027. 56 00:02:30.880 --> 00:02:33.760 Avery: Front row. See to a star's dramatic life. 57 00:02:34.000 --> 00:02:34.560 Love it. 58 00:02:34.800 --> 00:02:37.440 Anna: Next, NASA dropped an incredible video 59 00:02:37.520 --> 00:02:40.460 that's literally decades in the making. A 60 00:02:40.460 --> 00:02:43.340 time lapse of Kepler's supernova remnant 61 00:02:43.340 --> 00:02:45.820 from Chandra Xway Observatory data. 62 00:02:46.220 --> 00:02:48.260 Avery: This is the remnant from the supernova 63 00:02:48.260 --> 00:02:51.020 spotted by Johannes Kepler in 1604. 64 00:02:51.180 --> 00:02:54.060 A, uh, type 1A explosion from a white dwarf 65 00:02:54.060 --> 00:02:56.300 that blew up after Gaining too much mass, 66 00:02:56.620 --> 00:02:59.420 maybe from a companion or merger. It's about 67 00:02:59.500 --> 00:03:01.820 17,000 light years away and 68 00:03:01.820 --> 00:03:03.820 Chandra's been watching since 2000. 69 00:03:04.300 --> 00:03:06.700 Anna: The video combines observations from 70 00:03:06.700 --> 00:03:10.700 2000-2004-2006-2014 71 00:03:10.860 --> 00:03:13.480 and even in 2025 over 72 00:03:13.560 --> 00:03:16.440 25 years. It shows this neon 73 00:03:16.440 --> 00:03:19.320 blue X ray ring expanding like a balloon 74 00:03:19.480 --> 00:03:22.360 overlaid on optical light. The bottom side 75 00:03:22.360 --> 00:03:25.240 blasts out faster at 13.8 76 00:03:25.240 --> 00:03:28.160 million miles per hour while the top lags 77 00:03:28.160 --> 00:03:30.520 at 4 million miles per hour because it hits 78 00:03:30.520 --> 00:03:32.360 denser gas, Chandra. 79 00:03:32.360 --> 00:03:34.960 Avery: Glows in blue from million degree material 80 00:03:34.960 --> 00:03:37.080 and the rim measurements tell us about the 81 00:03:37.080 --> 00:03:39.920 explosion's power and surroundings. It's the 82 00:03:39.920 --> 00:03:42.920 longest spanning Chandra video ever showing 83 00:03:43.380 --> 00:03:45.780 remnant crashes into space stuff hurling 84 00:03:45.780 --> 00:03:47.860 elements for new stars and planets. 85 00:03:48.340 --> 00:03:51.300 Anna: Mind blowing to see cosmic history unfold. 86 00:03:51.540 --> 00:03:54.260 Avery: Frame by frame Shifting closer to 87 00:03:54.260 --> 00:03:57.060 home, a uh new all sky census of over 88 00:03:57.060 --> 00:03:59.499 2100 K dwarfs within about 89 00:03:59.499 --> 00:04:02.460 130 light years reveals some prime real 90 00:04:02.460 --> 00:04:04.980 estate for potential life bearing planets. 91 00:04:05.300 --> 00:04:08.140 Anna: K dwarfs are cooler, fainter orange 92 00:04:08.140 --> 00:04:10.860 stars twice as common as sun like G 93 00:04:10.860 --> 00:04:13.580 dwarfs nearby and they live way longer, 94 00:04:13.580 --> 00:04:16.120 giving planets stable rates radiation for 95 00:04:16.120 --> 00:04:19.000 billions more years Perfect for life to 96 00:04:19.000 --> 00:04:20.000 evolve slowly. 97 00:04:20.240 --> 00:04:22.640 Avery: The team use high res spectrometers on 98 00:04:22.640 --> 00:04:25.600 telescopes in Chile and Arizona for full sky 99 00:04:25.600 --> 00:04:27.920 coverage. They measured temperatures, 100 00:04:28.000 --> 00:04:30.720 ages, spin rates, magnetic activity 101 00:04:31.040 --> 00:04:33.800 all key for habitability since flaring 102 00:04:33.800 --> 00:04:35.520 stars can strip atmospheres. 103 00:04:35.920 --> 00:04:38.880 Anna: This spectroscopic recon is a goldmine 104 00:04:38.880 --> 00:04:41.840 data set for future exoplanet hunts and even 105 00:04:41.920 --> 00:04:44.800 interstellar travel planning Presented just 106 00:04:44.800 --> 00:04:46.720 this week at the AAS meeting. 107 00:04:47.420 --> 00:04:50.140 Foundational for decades makes you wonder 108 00:04:50.140 --> 00:04:50.380 how. 109 00:04:50.380 --> 00:04:52.540 Avery: Many Earth likes are chilling around these 110 00:04:52.540 --> 00:04:53.420 steady stars. 111 00:04:53.660 --> 00:04:56.060 Anna: For sky watchers, especially down south, 112 00:04:56.300 --> 00:04:59.220 2026 has some lunar a red 113 00:04:59.220 --> 00:05:02.020 moon from a total eclipse, a blue moon and 114 00:05:02.020 --> 00:05:04.060 a Christmas Eve supermoon. 115 00:05:04.300 --> 00:05:07.140 Avery: The total lunar eclipse on March 3 evening 116 00:05:07.140 --> 00:05:09.620 will turn the moon coppery red as Earth's 117 00:05:09.620 --> 00:05:12.140 atmosphere bends sunset light onto it. 118 00:05:12.380 --> 00:05:14.780 Totality's best from the Southern hemisphere 119 00:05:14.780 --> 00:05:17.740 Australia, New Zealand lasting about an hour 120 00:05:18.060 --> 00:05:20.820 visible even in cities Naked eye Then a. 121 00:05:20.820 --> 00:05:23.700 Anna: Blue moon on May 31 the second full 122 00:05:23.700 --> 00:05:26.140 moon in a month. A calendar quirk every 123 00:05:26.140 --> 00:05:28.620 couple years and December 24 124 00:05:28.620 --> 00:05:31.180 supermoon full moon at perigee 125 00:05:31.340 --> 00:05:34.260 looking bigger and brighter. Perfect illusion 126 00:05:34.260 --> 00:05:35.100 at moonrise. 127 00:05:35.500 --> 00:05:38.100 Avery: No equipment needed. Safe to watch. Mark 128 00:05:38.100 --> 00:05:40.220 those calendars for some magical nights. 129 00:05:40.620 --> 00:05:43.420 Anna: Now Headline grabber Could a passing 130 00:05:43.500 --> 00:05:46.060 star fling Earth into deep space, 131 00:05:46.380 --> 00:05:48.940 destabilising our orbit faster than thought? 132 00:05:49.550 --> 00:05:52.150 Avery: This comes from simulations by Nathan Kaib 133 00:05:52.150 --> 00:05:54.630 and Sean Raymond factoring in galactic 134 00:05:54.630 --> 00:05:57.350 flybys stars passing within 100 135 00:05:57.350 --> 00:06:00.190 AU at slow speeds. Normally 136 00:06:00.190 --> 00:06:03.070 solar system models assume isolation, but 137 00:06:03.150 --> 00:06:04.990 Reality includes these encounters. 138 00:06:05.390 --> 00:06:08.150 Anna: Mercury's the weak link. A flyby could make 139 00:06:08.150 --> 00:06:11.030 its orbit more eccentric, leading to crashes 140 00:06:11.030 --> 00:06:13.790 or tugs that cascade outward. Maybe 141 00:06:13.790 --> 00:06:16.430 Venus or Mars Nudging Earth toward 142 00:06:16.430 --> 00:06:18.750 Jupiter for a slingshot ejection. 143 00:06:19.310 --> 00:06:22.110 Avery: Probability about 0.2% 144 00:06:22.110 --> 00:06:24.630 chance over the next 5 billion years for 145 00:06:24.630 --> 00:06:27.590 Earth ejection or collision Tiny, 146 00:06:27.590 --> 00:06:30.510 but higher than old estimates. Pluto's risk 147 00:06:30.510 --> 00:06:33.350 is 4 to 5%, based on Gaia 148 00:06:33.350 --> 00:06:36.230 data and AARXIVE paper Real science. But 149 00:06:36.230 --> 00:06:38.510 the article amps up the drama with hidden 150 00:06:38.510 --> 00:06:39.310 threat vibes. 151 00:06:39.550 --> 00:06:41.870 Anna: Comforting to know it's super rare. Are 152 00:06:41.870 --> 00:06:43.310 orbits stable for aeons? 153 00:06:43.870 --> 00:06:46.510 Avery: Last up Is asteroid mining actually 154 00:06:46.670 --> 00:06:49.670 feasible? New chemistry data from meteorites 155 00:06:49.670 --> 00:06:52.090 offers sobering but insightful answers. 156 00:06:52.490 --> 00:06:55.290 Anna: Researchers analysed Carbonius chondrites 157 00:06:55.290 --> 00:06:58.210 proxies for C type asteroids. Measuring 158 00:06:58.210 --> 00:07:01.210 46 elements, these primitive rocks 159 00:07:01.210 --> 00:07:03.730 mix metals, silicates, water 160 00:07:03.730 --> 00:07:06.010 bearing stuff. But impacts create 161 00:07:06.010 --> 00:07:08.930 breccias and regolith, making separation 162 00:07:08.930 --> 00:07:10.330 tough in low gravity. 163 00:07:10.650 --> 00:07:13.370 Avery: Some groups show enriched titanium or rare 164 00:07:13.370 --> 00:07:16.330 Earths, but overall depleted in easy metals 165 00:07:16.330 --> 00:07:19.330 like copper. Water alteration oxidises 166 00:07:19.330 --> 00:07:21.950 things, complicating extraction. Led by 167 00:07:21.950 --> 00:07:24.910 Joseph Tirigo Rodriguez and team, it suggests 168 00:07:24.910 --> 00:07:27.510 mining's hard for bulk profit, better for 169 00:07:27.510 --> 00:07:30.350 targeted water or in space manufacturing. 170 00:07:30.670 --> 00:07:33.590 Anna: Focus on sample returns like Osiris Rex 171 00:07:33.590 --> 00:07:36.150 to pick winners. Feasible eventually with 172 00:07:36.150 --> 00:07:38.870 tech advances, but not a quick space gold 173 00:07:38.870 --> 00:07:39.310 rush. 174 00:07:39.710 --> 00:07:42.030 Avery: Realistic view Space resources for 175 00:07:42.030 --> 00:07:44.270 exploration, not Earth riches. 176 00:07:44.510 --> 00:07:44.990 Anna: Whew. 177 00:07:45.040 --> 00:07:47.670 Uh, from stellar companions to lunar lights 178 00:07:47.670 --> 00:07:50.110 in cosmic risks, what a ride Today. 179 00:07:50.630 --> 00:07:52.630 Avery: The universe never runs out of storeys. 180 00:07:52.710 --> 00:07:54.670 Thanks for joining us on Astronomy Daily. 181 00:07:54.670 --> 00:07:57.510 Anna: We appreciate every listen, subscribe, share 182 00:07:57.510 --> 00:07:59.750 and we'll catch you tomorrow with more. Keep 183 00:07:59.750 --> 00:08:01.350 looking up Clear skive.