WEBVTT 00:00:07.650 --> 00:00:10.289 Howdy Star Gazers and welcome to this episode 00:00:10.289 --> 00:00:13.730 of Star Trails. Drew here and I'll be your guide 00:00:13.730 --> 00:00:16.989 to the night sky for the week starting May 18th 00:00:16.989 --> 00:00:21.050 through the 24th. This week the moon wanes and 00:00:21.050 --> 00:00:24.510 the early morning sky comes alive. We'll also 00:00:24.510 --> 00:00:27.190 take a journey back into history and learn about 00:00:27.190 --> 00:00:29.989 one of the largest constellations in the sky, 00:00:30.239 --> 00:00:34.119 and why it doesn't exist anymore. Also, did you 00:00:34.119 --> 00:00:37.600 know there was once a house cat in the sky? More 00:00:37.600 --> 00:00:40.320 on that later. Whether you're tuning in from 00:00:40.320 --> 00:00:43.399 the backyard, the balcony, or just your imagination, 00:00:43.780 --> 00:00:47.179 I'm glad you're here. So find a cozy spot, let 00:00:47.179 --> 00:00:50.159 your eyes adjust, and let's see what the sky 00:00:50.159 --> 00:00:54.479 holds for us this week. Let's start with the 00:00:54.479 --> 00:00:58.210 moon. On May 18th, it's in a waning gibbous phase, 00:00:58.609 --> 00:01:01.210 still bright in the sky but shrinking each night. 00:01:01.789 --> 00:01:04.609 By the 20th, we hit the last quarter, meaning 00:01:04.609 --> 00:01:07.810 the moon rises around midnight and leaves us 00:01:07.810 --> 00:01:11.450 with dark skies after it sets. And by the end 00:01:11.450 --> 00:01:13.909 of the week, we're deep into the waning crescent 00:01:13.909 --> 00:01:17.150 phase, which means prime conditions for hunting 00:01:17.150 --> 00:01:21.670 faint galaxies and star clusters. Now onto the 00:01:21.670 --> 00:01:24.939 planets. In the evening Jupiter is hanging low 00:01:24.939 --> 00:01:28.219 in the western sky after sunset. It's getting 00:01:28.219 --> 00:01:31.700 closer to the sun's glare each night, so catch 00:01:31.700 --> 00:01:35.459 it while you can. Mars is much easier to spot, 00:01:35.840 --> 00:01:39.280 glowing reddish high overhead after dark. It's 00:01:39.280 --> 00:01:41.900 a great target this week, especially with less 00:01:41.900 --> 00:01:46.099 moonlight to compete. If you're an early riser, 00:01:46.280 --> 00:01:49.719 the morning sky has even more going on. Venus 00:01:49.719 --> 00:01:52.959 is blazing away in the eastern pre -dawn hours. 00:01:53.159 --> 00:01:55.239 It's the brightest thing in the sky other than 00:01:55.239 --> 00:01:58.680 the moon. Look above it and you'll find Saturn, 00:01:59.140 --> 00:02:02.219 more subdued but still visible without a telescope. 00:02:02.900 --> 00:02:05.959 And just before sunrise, try spotting Mercury. 00:02:06.400 --> 00:02:09.699 It's hugging the eastern horizon and can be tricky, 00:02:09.960 --> 00:02:13.319 but it's worth the challenge. Meanwhile, spring 00:02:13.319 --> 00:02:16.520 constellations are still putting on a show. Look 00:02:16.520 --> 00:02:20.439 south for Virgo and Leo, or trace the arc of 00:02:20.439 --> 00:02:24.240 Boötes, where bright orange Arcturus anchors 00:02:24.240 --> 00:02:27.900 the view. This is also a fantastic week to aim 00:02:27.900 --> 00:02:33.460 for deep -sky gems like M13 in Hercules or M5 00:02:33.460 --> 00:02:36.759 in Serpens, especially now that the moon isn't 00:02:36.759 --> 00:02:47.159 hogging the spotlight. Before we get into the 00:02:47.159 --> 00:02:49.780 second half of the show, I have a little housekeeping 00:02:49.780 --> 00:02:53.780 to discuss. As we end May and head into summer, 00:02:54.580 --> 00:02:56.680 astronomy starts becoming difficult for many 00:02:56.680 --> 00:02:59.900 of us. Moving towards the summer solstice, the 00:02:59.900 --> 00:03:02.840 days will grow much longer, affording us less 00:03:02.840 --> 00:03:06.879 observation time. Increased heat and crazy summer 00:03:06.879 --> 00:03:10.020 weather can be a problem for some of us. For 00:03:10.020 --> 00:03:12.599 example, here in the southeast U .S., summer 00:03:12.599 --> 00:03:16.659 brings haze, humidity, and daily thunderstorms. 00:03:16.759 --> 00:03:19.860 Not to mention 90 degree temperatures, mosquitoes, 00:03:20.219 --> 00:03:23.780 and other pests. So all this to say, I won't 00:03:23.780 --> 00:03:26.560 be doing a lot of observation for the next 3 00:03:26.560 --> 00:03:29.960 or 4 months. I haven't decided if the show will 00:03:29.960 --> 00:03:33.180 continue to be weekly during the summer or whether 00:03:33.180 --> 00:03:36.599 I'll try releasing every 2 weeks. If you have 00:03:36.599 --> 00:03:39.939 any opinions on this, go to StarTrails .Show 00:03:39.939 --> 00:03:44.210 and let me know. Also, last year, right before 00:03:44.210 --> 00:03:47.270 our December break, I mentioned that I would 00:03:47.270 --> 00:03:50.569 be reading Nightwatch, a practical guide to viewing 00:03:50.569 --> 00:03:54.250 the universe, by Terence Dickinson. This is a 00:03:54.250 --> 00:03:57.990 popular book for backyard astronomers. Well, 00:03:58.069 --> 00:04:01.110 sadly, I never got around to reading it, so I 00:04:01.110 --> 00:04:03.909 apologize to anyone who was hoping for a Star 00:04:03.909 --> 00:04:07.870 Trails book club moment. I do plan to start reading 00:04:07.870 --> 00:04:10.650 it soon, especially since observation will be 00:04:10.650 --> 00:04:13.689 rough for me in the coming weeks. I'll report 00:04:13.689 --> 00:04:15.930 back with my thoughts on this book in a future 00:04:15.930 --> 00:04:20.089 episode. This book is often cited as a must -read 00:04:20.089 --> 00:04:23.129 for backyard astronomers, so be sure to get the 00:04:23.129 --> 00:04:32.850 fifth edition, which is the latest version. Today 00:04:32.850 --> 00:04:35.810 we're going to discuss some constellations of 00:04:35.810 --> 00:04:39.110 the southern sky. Regular listeners know that 00:04:39.110 --> 00:04:42.370 we generally focus on the skies over North America, 00:04:42.529 --> 00:04:46.389 so this may be unfamiliar territory. I was once 00:04:46.389 --> 00:04:49.370 told by an astronomer that the southern hemisphere 00:04:49.370 --> 00:04:52.769 wasn't as impressive as the northern. He said, 00:04:53.069 --> 00:04:56.269 and I quote, all they have are some Magellanic 00:04:56.269 --> 00:04:59.649 clouds. This couldn't be farther from the truth. 00:04:59.850 --> 00:05:02.649 I once spent several weeks in Australia, and 00:05:02.649 --> 00:05:05.430 one night in the country I was able to see a 00:05:05.430 --> 00:05:08.769 stunningly dark, clear night sky filled with 00:05:08.769 --> 00:05:12.449 dazzling, unfamiliar patterns. While the northern 00:05:12.449 --> 00:05:15.550 sky is home to some of the most iconic and familiar 00:05:15.550 --> 00:05:20.089 constellations, like Ursa Major, Orion, and Cassiopeia, 00:05:20.449 --> 00:05:23.449 it offers a more edge -on view of the Milky Way. 00:05:23.660 --> 00:05:27.100 That means we see a thinner, less dense section 00:05:27.100 --> 00:05:30.259 of our galaxy, but it's rich in recognizable 00:05:30.259 --> 00:05:33.319 shapes and nearby objects like the Andromeda 00:05:33.319 --> 00:05:37.540 Galaxy and the Pleiades Cluster. Polaris, the 00:05:37.540 --> 00:05:41.420 North Star, also makes navigation easy, and centuries 00:05:41.420 --> 00:05:44.699 of mythology have helped etch these constellations 00:05:44.699 --> 00:05:48.899 deep into cultural memory. But head south and 00:05:48.899 --> 00:05:52.560 the sky explodes with drama. The Southern Hemisphere 00:05:52.560 --> 00:05:55.660 gives us a direct line of sight to the galactic 00:05:55.660 --> 00:05:59.160 core, where the Milky Way appears brighter, denser, 00:05:59.319 --> 00:06:02.819 and far more intricate. It hosts the Southern 00:06:02.819 --> 00:06:06.199 Cross, the dazzling Carina Nebula, which we'll 00:06:06.199 --> 00:06:09.819 discuss in a moment, the massive Omega Centauri 00:06:09.819 --> 00:06:13.360 Cluster, and even entire satellite galaxies, 00:06:13.680 --> 00:06:17.220 the large and small Magellanic Clouds that my 00:06:17.220 --> 00:06:21.019 astronomer friend was so dismissive of. The reason 00:06:21.019 --> 00:06:23.680 I mention this is because the southern sky was 00:06:23.680 --> 00:06:26.920 home to a fascinating constellation that doesn't 00:06:26.920 --> 00:06:29.899 exist anymore. There's actually a whole cast 00:06:29.899 --> 00:06:32.899 of constellations that used to exist and don't 00:06:32.899 --> 00:06:35.720 anymore. And none of them were quite as grand 00:06:35.720 --> 00:06:40.000 or as doomed as Argo Navus, the ship that got 00:06:40.000 --> 00:06:43.759 sunk by astronomers. This was once a constellation 00:06:43.759 --> 00:06:47.240 so big, so sprawling, it had to be broken up 00:06:47.240 --> 00:06:50.220 like a decommissioned schooner at a shipyard. 00:06:50.980 --> 00:06:53.540 Argo Navus was named after the mythical ship 00:06:53.540 --> 00:06:57.160 Argo, the one Jason and the Argonauts sailed 00:06:57.160 --> 00:06:59.759 on during their legendary quest for the Golden 00:06:59.759 --> 00:07:04.399 Fleece. This is classic Greek mythology. The 00:07:04.399 --> 00:07:07.220 constellation was first catalogued by Claudius 00:07:07.220 --> 00:07:11.060 Ptolemy in the 2nd century CE, during the golden 00:07:11.060 --> 00:07:14.639 age of ancient astronomy. Back then, they weren't 00:07:14.639 --> 00:07:17.939 too concerned with how huge this thing was. It 00:07:17.939 --> 00:07:20.939 sprawled across a massive chunk of the southern 00:07:20.939 --> 00:07:24.759 sky. To give you an idea of its size, if you 00:07:24.759 --> 00:07:28.980 took Orion, Canis Major, and Gemini, and smashed 00:07:28.980 --> 00:07:31.920 them all into one mega constellation, that's 00:07:31.920 --> 00:07:35.000 the scale we're talking about. For centuries, 00:07:35.379 --> 00:07:38.720 Argo Navus stood as the largest single constellation 00:07:38.720 --> 00:07:41.959 in the sky, but it had a problem. Simply, it 00:07:41.959 --> 00:07:46.360 was really, really impractical. By the 1700s, 00:07:46.660 --> 00:07:49.319 astronomers started to feel like Argo Navis was 00:07:49.319 --> 00:07:52.639 less of a constellation and more of a mess. It 00:07:52.639 --> 00:07:56.660 had hundreds of stars and no clear borders. Trying 00:07:56.660 --> 00:07:59.740 to map or reference anything inside it was like 00:07:59.740 --> 00:08:02.459 trying to navigate a ship with three captains 00:08:02.459 --> 00:08:06.439 shouting different directions. Enter Nicolas 00:08:06.439 --> 00:08:10.879 -Louis Delacay, an 18th century French astronomer. 00:08:11.069 --> 00:08:13.870 He was mapping the southern skies from the Cape 00:08:13.870 --> 00:08:19.389 of Good Hope in South Africa. In 1763, Lakai 00:08:19.389 --> 00:08:23.389 decided enough was enough. He chopped Argo Navus 00:08:23.389 --> 00:08:27.089 into three new nautical -themed constellations, 00:08:27.649 --> 00:08:31.149 and they've stuck ever since. There's Carina, 00:08:31.490 --> 00:08:35.600 the keel of the ship. Pupus, the stern, also 00:08:35.600 --> 00:08:39.360 known as the poop deck, and Vela, the sails. 00:08:39.779 --> 00:08:43.000 And just like that, the mighty Argo Navus was 00:08:43.000 --> 00:08:46.460 no more. Of course, just because the name disappeared 00:08:46.460 --> 00:08:50.480 doesn't mean the stars did. These three new constellations 00:08:50.480 --> 00:08:55.320 inherited all kinds of celestial treasures. Carina 00:08:55.320 --> 00:08:58.600 is home to Canopus, the second brightest star 00:08:58.600 --> 00:09:02.179 in the night sky, just behind Sirius. For viewers 00:09:02.179 --> 00:09:05.200 in the Southern Hemisphere, Canopus is a brilliant 00:09:05.200 --> 00:09:09.519 white beacon low on the horizon. Deep in Carinna 00:09:09.519 --> 00:09:13.059 lies the Carinna Nebula, one of the largest star 00:09:13.059 --> 00:09:16.740 -forming regions visible from Earth. Inside it, 00:09:16.759 --> 00:09:20.019 we find the massive and unstable Etta Carini, 00:09:20.299 --> 00:09:24.019 a binary star system so volatile it once brightened 00:09:24.019 --> 00:09:27.379 the sky in the 1800s to become the second brightest 00:09:27.379 --> 00:09:31.820 star for a time. Let's drift over to Vela. Its 00:09:31.820 --> 00:09:35.279 most famous feature is the Vela Supernova Remnant, 00:09:35.820 --> 00:09:38.860 a massive bubble of gas and dust left behind 00:09:38.860 --> 00:09:42.919 by a star that exploded about 11 ,000 years ago. 00:09:43.500 --> 00:09:48.059 Its ghost is still expanding through space. Inside 00:09:48.059 --> 00:09:52.120 the remnant is the Vela Pulsar, a rapidly spinning 00:09:52.120 --> 00:09:56.200 neutron star beaming out radio waves like a cosmic 00:09:56.200 --> 00:10:02.399 lighthouse. Pupus is home to Messier 93, an open 00:10:02.399 --> 00:10:05.779 -star cluster tightly packed with hot young stars. 00:10:06.360 --> 00:10:12.240 There's also NGC 2467, a vibrant nebula sometimes 00:10:12.240 --> 00:10:15.700 called the Skull and Crossbones Nebula. Despite 00:10:15.700 --> 00:10:19.080 its eerie nickname, it's actually a stellar nursery. 00:10:20.019 --> 00:10:23.259 So even though Argonavis, as a name, is gone, 00:10:23.620 --> 00:10:26.440 its pieces are alive and well. filled with some 00:10:26.440 --> 00:10:29.039 of the most dazzling and active regions of the 00:10:29.039 --> 00:10:33.399 Milky Way. Of course, Argo wasn't the only constellation 00:10:33.399 --> 00:10:36.940 to get the axe. Here are a few other sky figures 00:10:36.940 --> 00:10:40.720 that were edited out of the final draft. Quadrons 00:10:40.720 --> 00:10:43.879 Morales was a northern hemisphere constellation 00:10:43.879 --> 00:10:47.620 created in the 18th century and named after a 00:10:47.620 --> 00:10:50.879 wall -mounted astronomical instrument, the quadrant. 00:10:51.279 --> 00:10:54.500 It no longer exists officially, but its name 00:10:54.500 --> 00:10:57.799 survives in the quadrantid meteor shower that 00:10:57.799 --> 00:11:02.980 peaks in early January. Felis, the cat, was a 00:11:02.980 --> 00:11:06.519 house cat in the sky. It was introduced by French 00:11:06.519 --> 00:11:11.259 astronomer Joseph -Jérôme de la Londe in 1799 00:11:11.259 --> 00:11:15.220 because, as he put it, cats deserve to be represented. 00:11:15.690 --> 00:11:20.610 The IAU disagreed and poor Phelous got booted 00:11:20.610 --> 00:11:25.629 in 1922. The constellation was located near Hydra. 00:11:26.009 --> 00:11:28.629 While it's not acknowledged anymore, its brightest 00:11:28.629 --> 00:11:31.929 star, Phelous, is a reminder that it existed 00:11:31.929 --> 00:11:35.370 and is quite an interesting star in its own right. 00:11:36.429 --> 00:11:39.230 Located more than 600 light years from Earth, 00:11:39.500 --> 00:11:43.159 Felis is an orange -red giant with a high proper 00:11:43.159 --> 00:11:46.580 motion. That's the apparent movement of the star 00:11:46.580 --> 00:11:51.200 compared to others in the sky. And finally, Antinous 00:11:51.200 --> 00:11:54.419 is another constellation that was quietly retired. 00:11:55.139 --> 00:11:58.419 A tragic figure from Roman history, Antinous 00:11:58.419 --> 00:12:02.419 was Hadrian's young lover. He was later deified 00:12:02.419 --> 00:12:06.570 and immortalized as a star pattern. The constellation 00:12:06.570 --> 00:12:10.610 was removed from charts in 1922 and became part 00:12:10.610 --> 00:12:14.950 of the constellation Aquila. More recently, the 00:12:14.950 --> 00:12:18.450 IAU working group on star names approved the 00:12:18.450 --> 00:12:22.850 name Antinous for the star Theta Aquili in 2024 00:12:22.850 --> 00:12:27.090 in honor of the defunct constellation. If there's 00:12:27.090 --> 00:12:29.970 any lesson here, it's that the sky is always 00:12:29.970 --> 00:12:33.980 evolving. constellations aren't permanent. They're 00:12:33.980 --> 00:12:37.340 cultural artifacts shaped by who we are, what 00:12:37.340 --> 00:12:40.580 we believe, and how we explore the universe. 00:12:41.440 --> 00:12:44.000 They remind us that the tapestry of the cosmos 00:12:44.000 --> 00:12:47.820 is a mirror of our evolving time here on Earth. 00:12:52.899 --> 00:12:55.620 If the stars spoke to you this week, or if a 00:12:55.620 --> 00:12:58.100 question's been on your mind, I'd love to hear 00:12:58.100 --> 00:13:02.200 it. visit our website, StarTrails .Show, where 00:13:02.200 --> 00:13:05.539 you can contact me and explore past episodes. 00:13:06.440 --> 00:13:10.080 Be sure to follow us on Mastodon, Blue Sky, and 00:13:10.080 --> 00:13:13.740 YouTube. Links are in the show notes. Until we 00:13:13.740 --> 00:13:17.000 meet again beneath the stars, clear skies everyone.