WEBVTT 00:00:07.569 --> 00:00:10.509 Howdy Star Gazers and welcome to this episode 00:00:10.509 --> 00:00:13.750 of Star Trails. Drew here and I'll be your guide 00:00:13.750 --> 00:00:16.190 to the night sky for the week starting June the 00:00:16.190 --> 00:00:20.370 15th through the 21st. This week we'll check 00:00:20.370 --> 00:00:23.769 in on the moon, a few bright planets, and the 00:00:23.769 --> 00:00:27.640 rising galactic core. Then we'll take a step 00:00:27.640 --> 00:00:30.600 back in time to explore how ancient cultures 00:00:30.600 --> 00:00:33.500 watched and tracked the skies, including the 00:00:33.500 --> 00:00:36.320 story of a 2 ,000 year old device pulled from 00:00:36.320 --> 00:00:39.100 a shipwreck that turned out to be the world's 00:00:39.100 --> 00:00:42.560 first computer. Whether you're tuning in from 00:00:42.560 --> 00:00:45.600 the backyard, the balcony, or just your imagination, 00:00:45.960 --> 00:00:49.200 I'm glad you're here. So find a cozy spot, let 00:00:49.200 --> 00:00:51.799 your eyes adjust, and let's see what the sky 00:00:51.799 --> 00:00:56.549 holds for us this week. Let's start with the 00:00:56.549 --> 00:00:59.450 moon, since it tends to dominate our evening 00:00:59.450 --> 00:01:03.090 sky this week. Tonight the moon is in its waning 00:01:03.090 --> 00:01:07.689 gibbous phase, about 87 % illuminated, and rises 00:01:07.689 --> 00:01:11.150 a little after sunset. Each night this week, 00:01:11.349 --> 00:01:14.650 it'll rise later and later, shrinking as it does. 00:01:15.189 --> 00:01:18.950 By Wednesday the 18th, it reaches the last quarter, 00:01:19.310 --> 00:01:22.010 looking like a perfect half -circle in the pre 00:01:22.010 --> 00:01:26.109 -dawn hours. After that, the moon becomes a waning 00:01:26.109 --> 00:01:28.989 crescent, rising in the wee hours of the morning 00:01:28.989 --> 00:01:31.790 and becoming harder to spot as it approaches 00:01:31.790 --> 00:01:37.030 the new moon on the 25th. One subtle treat arrives 00:01:37.030 --> 00:01:41.090 on June 23 when the moon reaches Perigee, its 00:01:41.090 --> 00:01:43.890 closest approach to Earth in its monthly orbit, 00:01:44.430 --> 00:01:49.469 sitting about 225 ,000 miles away. Perigee also 00:01:49.469 --> 00:01:52.689 means slightly stronger ocean tides, and for 00:01:52.689 --> 00:01:56.069 the keen -eyed, a slightly larger lunar disk. 00:01:56.950 --> 00:02:00.290 The planetary lineup this week spans both dusk 00:02:00.290 --> 00:02:03.909 and dawn. Right after sunset, the western sky 00:02:03.909 --> 00:02:07.010 gives us two familiar travelers, Mercury and 00:02:07.010 --> 00:02:10.729 Mars. Mercury is beginning a brief but favorable 00:02:10.729 --> 00:02:14.710 evening sight. On the 15th it appears about 74 00:02:14.710 --> 00:02:17.710 % illuminated through a telescope and shines 00:02:17.710 --> 00:02:22.189 at magnitude 0 .3, not its brightest, but visible 00:02:22.189 --> 00:02:24.909 if you've got a clear, flat western horizon. 00:02:25.990 --> 00:02:28.590 Mercury sets about 90 minutes after the sun, 00:02:28.650 --> 00:02:32.750 so you'll need to catch it quickly. By June 24th, 00:02:32.770 --> 00:02:35.229 it'll be part of a neat lineup with the bright 00:02:35.229 --> 00:02:39.050 Gemini twins, Castor and Pollux, hovering just 00:02:39.050 --> 00:02:41.919 above the western horizon. If you catch it at 00:02:41.919 --> 00:02:44.680 twilight, you'll see Mercury sitting below those 00:02:44.680 --> 00:02:48.419 two stars in a graceful vertical line. A little 00:02:48.419 --> 00:02:51.800 higher in the sky, Mars is making its slow passage 00:02:51.800 --> 00:02:55.180 through the constellation Leo. Its orange glow 00:02:55.180 --> 00:02:59.139 contrasts beautifully with Regulus, Leo's bright 00:02:59.139 --> 00:03:02.740 blue -white heart star. Look for a close approach 00:03:02.740 --> 00:03:06.560 with these objects on the 16th and 17th. The 00:03:06.560 --> 00:03:09.759 pre -dawn sky is where the real planetary action 00:03:09.759 --> 00:03:13.860 unfolds this week. There you'll find Venus rising 00:03:13.860 --> 00:03:16.580 brightly in the east about 90 minutes before 00:03:16.580 --> 00:03:21.379 sunrise. At magnitude negative 3 .9, it's the 00:03:21.379 --> 00:03:23.759 brightest object in the sky besides the moon 00:03:23.759 --> 00:03:27.360 and sun. Just to its upper right, you'll find 00:03:27.360 --> 00:03:30.620 Saturn glowing pale yellow in the constellation 00:03:30.620 --> 00:03:34.699 Aquarius. On the 19th, the moon will drift nearby 00:03:34.699 --> 00:03:38.379 Saturn in the early morning sky, creating a gorgeous 00:03:38.379 --> 00:03:41.860 pre -dawn pairing. If you're up around 3 or 4 00:03:41.860 --> 00:03:45.659 a .m., it's worth stepping outside for. Jupiter, 00:03:45.680 --> 00:03:48.539 on the other hand, is making its quiet exit. 00:03:48.900 --> 00:03:51.759 It's low in the west before dawn and gets lost 00:03:51.759 --> 00:03:55.099 in the sun's glare by June 24th, when it reaches 00:03:55.099 --> 00:03:58.520 solar conjunction. That means it's passing directly 00:03:58.520 --> 00:04:01.919 behind the sun from our point of view. It won't 00:04:01.919 --> 00:04:04.460 be visible again until it emerges in the morning 00:04:04.460 --> 00:04:09.039 sky in mid -July. For telescope users, Uranus 00:04:09.039 --> 00:04:12.259 and Neptune are both technically visible, but 00:04:12.259 --> 00:04:15.860 they're faint and require effort. Neptune sits 00:04:15.860 --> 00:04:18.399 near Saturn in the sky this week, though it's 00:04:18.399 --> 00:04:22.699 at magnitude 7 .9 and invisible without optical 00:04:22.699 --> 00:04:27.240 aid. Uranus rises before dawn in Aries but remains 00:04:27.240 --> 00:04:30.120 difficult to spot until it climbs higher in the 00:04:30.120 --> 00:04:40.040 coming weeks. Now let's pull back from the planets 00:04:40.040 --> 00:04:43.360 and take in the broader canvas of stars because 00:04:43.360 --> 00:04:46.319 this time of year the Milky Way really begins 00:04:46.319 --> 00:04:50.790 to show off. By mid -evening, say around 10 p 00:04:50.790 --> 00:04:54.089 .m., the Milky Way's bright central band begins 00:04:54.089 --> 00:04:57.529 to rise in the southeast. If you're under a dark 00:04:57.529 --> 00:05:01.089 sky free from streetlights and urban haze, you'll 00:05:01.089 --> 00:05:04.009 see a faint cloudy river of stars running from 00:05:04.009 --> 00:05:07.629 horizon to zenith. That's the galactic core, 00:05:08.170 --> 00:05:10.750 and June is one of the best times to see it in 00:05:10.750 --> 00:05:13.970 the Northern Hemisphere. Overhead, the summer 00:05:13.970 --> 00:05:17.750 triangle is fully visible. This prominent asterism 00:05:17.750 --> 00:05:21.550 is formed by three bright stars, Vega in the 00:05:21.550 --> 00:05:25.889 constellation Lyra, Deneb in Cygnus, and Altair 00:05:25.889 --> 00:05:29.490 in Aquila. Vega is the brightest of the three 00:05:29.490 --> 00:05:33.670 and nearly directly overhead. Deneb marks the 00:05:33.670 --> 00:05:37.389 tail of the celestial swan, and Altair, the eye 00:05:37.389 --> 00:05:40.769 of the eagle, flaps along the Milky Way's edge. 00:05:41.590 --> 00:05:44.529 Cygnus, also known as the Northern Cross, is 00:05:44.529 --> 00:05:47.910 a rich area to explore with binoculars. Look 00:05:47.910 --> 00:05:51.610 for clusters, dark nebulae, and star clouds tucked 00:05:51.610 --> 00:05:55.949 along the Milky Way's spine. To the west, Boötes 00:05:55.949 --> 00:05:59.350 and Arcturus still dominate the early evening. 00:05:59.990 --> 00:06:02.930 Arcturus is easy to find. Just follow the curve 00:06:02.930 --> 00:06:06.569 of the Big Dipper's handle and arc to Arcturus. 00:06:06.939 --> 00:06:10.939 This orange giant star is relatively close, about 00:06:10.939 --> 00:06:14.860 37 light -years away, and heading towards us. 00:06:15.540 --> 00:06:18.860 Near Boötes, you'll find Corona Borealis, the 00:06:18.860 --> 00:06:23.120 northern crown, a small but elegant arc of stars. 00:06:23.980 --> 00:06:26.720 And rising later in the east, the teapot -shaped 00:06:26.720 --> 00:06:30.319 Sagittarius begins to ascend, marking the gateway 00:06:30.319 --> 00:06:33.569 to the galactic center. We're still a few weeks 00:06:33.569 --> 00:06:36.709 away from any major meteor showers, but sporadic 00:06:36.709 --> 00:06:40.089 meteors can be seen on any clear night. And with 00:06:40.089 --> 00:06:42.949 the moon waning towards new this week, darker 00:06:42.949 --> 00:06:45.769 skies will make these background meteors even 00:06:45.769 --> 00:06:55.790 easier to spot. The summer solstice occurs on 00:06:55.790 --> 00:06:58.899 Friday. It's the longest day of the year and 00:06:58.899 --> 00:07:01.639 the moment when the sun reaches its highest point 00:07:01.639 --> 00:07:05.839 in the sky. The solstice is a reminder of a truth 00:07:05.839 --> 00:07:09.319 as old as humanity itself. People have always 00:07:09.319 --> 00:07:13.680 looked up. Long before telescopes or scientific 00:07:13.680 --> 00:07:16.939 journals, humans were watching the sky, tracking 00:07:16.939 --> 00:07:20.660 its rhythms and embedding its stories into stone, 00:07:21.019 --> 00:07:24.980 memory, and myth. The solstices, both summer 00:07:24.980 --> 00:07:28.360 and winter, acted as celestial bookmarks for 00:07:28.360 --> 00:07:31.540 ancient cultures, fixed points in the rhythm 00:07:31.540 --> 00:07:35.060 of the seasons. From the Arctic Circle to the 00:07:35.060 --> 00:07:38.920 Andes, they marked time by the sky, planting, 00:07:39.319 --> 00:07:42.100 harvesting, hunting, and praying according to 00:07:42.100 --> 00:07:45.100 the movements of the sun, moon, and the stars. 00:07:45.629 --> 00:07:49.209 Let's begin in prehistoric Europe, where monuments 00:07:49.209 --> 00:07:53.129 like Stonehenge align almost precisely with the 00:07:53.129 --> 00:07:56.970 rising sun on the summer solstice. When sunlight 00:07:56.970 --> 00:08:00.029 breaks over the heelstone and pours into the 00:08:00.029 --> 00:08:03.110 monument's center, it creates a striking visual 00:08:03.110 --> 00:08:06.589 that likely held spiritual, agricultural, or 00:08:06.589 --> 00:08:10.129 communal meaning. Constructed in several phases 00:08:10.129 --> 00:08:15.089 between roughly 3000 and 2000 BCE, Stonehenge 00:08:15.089 --> 00:08:18.509 incorporated massive rock formations transported 00:08:18.509 --> 00:08:23.490 from more than 150 miles away in Wales. Beyond 00:08:23.490 --> 00:08:27.050 solstice alignments, theories suggest Stonehenge 00:08:27.050 --> 00:08:30.269 may have functioned as a burial ground, ceremonial 00:08:30.269 --> 00:08:34.649 center, or a lunar calendar. Similar alignments 00:08:34.649 --> 00:08:37.929 appear in Ireland and Orkney, where solar events 00:08:37.929 --> 00:08:41.350 dictate how light enters stone passageways at 00:08:41.350 --> 00:08:45.070 exact times of year. These early engineers didn't 00:08:45.070 --> 00:08:48.190 use metal tools or mathematics as we know them, 00:08:48.429 --> 00:08:51.429 but they built with precision, using horizon 00:08:51.429 --> 00:08:54.809 markers and the human eye to measure time itself. 00:08:55.750 --> 00:08:58.830 Across the world in Mesopotamia, the Babylonians 00:08:58.830 --> 00:09:01.309 were developing what we might recognize as the 00:09:01.309 --> 00:09:04.830 first scientific astronomy. They recorded the 00:09:04.830 --> 00:09:08.070 rising and setting of stars, tracked eclipses, 00:09:08.149 --> 00:09:12.269 and used a base 60 number system that still influences 00:09:12.269 --> 00:09:15.870 how we measure time today. They also discovered 00:09:15.870 --> 00:09:19.909 the Saros cycle, an 18 -year period after which 00:09:19.909 --> 00:09:23.669 lunar and solar eclipses repeat. All of this 00:09:23.669 --> 00:09:26.649 was done without lenses, telescopes, or even 00:09:26.649 --> 00:09:30.110 basic optics. Their most sophisticated tools 00:09:30.110 --> 00:09:33.330 were observation, record -keeping, and patience. 00:09:34.289 --> 00:09:37.549 But for sheer ingenuity, few artifacts of the 00:09:37.549 --> 00:09:41.009 ancient world rival the Antikythera mechanism. 00:09:41.809 --> 00:09:44.610 Pulled from the sea off the coast of Greece in 00:09:44.610 --> 00:09:49.009 1901, this corroded mass of bronze gears remained 00:09:49.009 --> 00:09:52.009 a mystery for more than a century. Today, we 00:09:52.009 --> 00:09:55.470 know it to be an ancient computer. a mechanical 00:09:55.470 --> 00:09:59.870 device designed around 100 BCE to track the motions 00:09:59.870 --> 00:10:04.049 of the sun, moon, and five known planets. It 00:10:04.049 --> 00:10:07.549 even predicted eclipses and synchronized with 00:10:07.549 --> 00:10:11.529 the Olympic games. Recent studies revealed it 00:10:11.529 --> 00:10:14.490 used differential gearing and a sophisticated 00:10:14.490 --> 00:10:18.190 epicyclic model to account for the moon's elliptical 00:10:18.190 --> 00:10:22.220 orbit. a level of mechanical sophistication not 00:10:22.220 --> 00:10:26.820 seen again until the 18th century. Its back dials 00:10:26.820 --> 00:10:30.320 also recorded the metonic cycle, that's a 19 00:10:30.320 --> 00:10:33.080 -year cycle in which lunar phases recur at the 00:10:33.080 --> 00:10:37.419 same time, and eclipse predictions using Babylonian 00:10:37.419 --> 00:10:41.059 -style glyphs. It's the only device of its kind 00:10:41.059 --> 00:10:44.639 ever found suggesting a lost tradition of high 00:10:44.639 --> 00:10:48.120 -precision astronomical engineering in the Hellenistic 00:10:48.120 --> 00:10:52.039 world. The Greeks also gave us some of the earliest 00:10:52.039 --> 00:10:54.840 theoretical frameworks for understanding the 00:10:54.840 --> 00:10:59.100 sky. Aristarchus proposed a heliocentric model 00:10:59.100 --> 00:11:02.559 of the solar system around the 3rd century BCE, 00:11:03.220 --> 00:11:07.799 nearly 1800 years before Copernicus. Hipparchus, 00:11:08.080 --> 00:11:11.200 often called the father of trigonometry, developed 00:11:11.200 --> 00:11:14.700 the first comprehensive star catalog and discovered 00:11:14.700 --> 00:11:18.580 precession. That's the slow wobble in Earth's 00:11:18.580 --> 00:11:22.519 axis. And of course Ptolemy's geocentric model, 00:11:22.539 --> 00:11:25.720 though incorrect, dominated astronomical thought 00:11:25.720 --> 00:11:29.039 for more than a millennium, owning to its mathematical 00:11:29.039 --> 00:11:33.679 sophistication and explanatory power. These thinkers 00:11:33.679 --> 00:11:36.679 were beginning to shift astronomy from observational 00:11:36.679 --> 00:11:40.899 tradition into formal science. Over in ancient 00:11:40.899 --> 00:11:44.419 China, astronomers during the Shang dynasty and 00:11:44.419 --> 00:11:48.220 later eras kept detailed records of comets, eclipses, 00:11:48.419 --> 00:11:52.220 and planetary motions. They identified guest 00:11:52.220 --> 00:11:55.980 stars, what we now know as supernova, and connected 00:11:55.980 --> 00:11:58.980 celestial events to the Emperor's legitimacy. 00:11:59.480 --> 00:12:02.820 Royal astronomers operated with high stakes. 00:12:03.039 --> 00:12:05.879 Failing to predict an eclipse would cause political 00:12:05.879 --> 00:12:10.259 unrest or even cost them their lives. The Chinese 00:12:10.259 --> 00:12:13.000 were also among the first to document phenomena 00:12:13.000 --> 00:12:16.519 like Halley's Comet, and their star charts helped 00:12:16.519 --> 00:12:20.679 preserve sky positions across centuries. In the 00:12:20.679 --> 00:12:24.379 Inca Empire, solar observation was central to 00:12:24.379 --> 00:12:28.440 statecraft. Temples like Machu Picchu were aligned 00:12:28.440 --> 00:12:31.460 with solstices, and ritual pillars were believed 00:12:31.460 --> 00:12:36.039 to hold the sun in its proper path. Likewise, 00:12:36.460 --> 00:12:39.240 Mayan kings scheduled battles and ceremonies 00:12:39.240 --> 00:12:43.559 according to the Venus cycle. The Dresden Codex, 00:12:43.620 --> 00:12:46.580 one of the few surviving Mayan texts, contains 00:12:46.580 --> 00:12:50.460 incredibly precise Venus tables. Its appearances 00:12:50.460 --> 00:12:53.399 and disappearances were used to guide warfare. 00:12:53.580 --> 00:12:58.379 coronations, and sacrifices. Islamic scholars 00:12:58.379 --> 00:13:02.220 preserved and expanded on Greek knowledge. They 00:13:02.220 --> 00:13:05.639 developed astrolabes, improved star catalogs, 00:13:05.779 --> 00:13:08.919 and calculated planetary orbits with remarkable 00:13:08.919 --> 00:13:12.480 precision. And speaking of star maps, some of 00:13:12.480 --> 00:13:15.659 the most astonishing weren't drawn at all. They 00:13:15.659 --> 00:13:20.309 were sung. The Polynesians, navigating vast stretches 00:13:20.309 --> 00:13:23.490 of the Pacific, memorized the rising and setting 00:13:23.490 --> 00:13:26.210 points of stars to guide them between islands 00:13:26.210 --> 00:13:29.769 that were thousands of miles apart. Without metal 00:13:29.769 --> 00:13:33.129 tools or written maps, they used oral knowledge, 00:13:33.590 --> 00:13:36.970 wave patterns, bird behavior, and the stars to 00:13:36.970 --> 00:13:40.440 sail across the world's largest ocean. Their 00:13:40.440 --> 00:13:43.220 star compass divided the horizon into more than 00:13:43.220 --> 00:13:47.679 30 sectors each marked by a key star. This mental 00:13:47.679 --> 00:13:50.940 map was passed down through chance, ritual, and 00:13:50.940 --> 00:13:55.139 experience. We also see astonishing sky knowledge 00:13:55.139 --> 00:13:58.799 in indigenous cultures of North America and Australia. 00:13:59.600 --> 00:14:02.639 The Navajo, Lakota, and other Native American 00:14:02.639 --> 00:14:05.700 nations wove constellations into their moral 00:14:05.700 --> 00:14:09.710 teachings. agricultural cycles, and healing practices. 00:14:10.289 --> 00:14:12.909 In some traditions, the Milky Way was seen as 00:14:12.909 --> 00:14:16.649 the path of souls or a great river in the sky. 00:14:17.950 --> 00:14:21.649 What kind of tools made all this possible? Most 00:14:21.649 --> 00:14:25.190 ancient astronomers relied on naked eye observation 00:14:25.190 --> 00:14:29.320 and simple but clever instruments. One such instrument 00:14:29.320 --> 00:14:32.500 was the nomen, a stick planted vertically in 00:14:32.500 --> 00:14:34.840 the ground that could track the Sun's shadow 00:14:34.840 --> 00:14:39.340 to measure time and solstices. Egyptians used 00:14:39.340 --> 00:14:42.460 plumb lines and the stars to align structures 00:14:42.460 --> 00:14:46.600 and keep time at night. The armillary sphere, 00:14:47.019 --> 00:14:49.759 quadrant, and water clocks were used by Greeks, 00:14:50.120 --> 00:14:54.000 Chinese, and Arabs to refine measurements. Of 00:14:54.000 --> 00:14:57.059 course, the stars weren't only mapped, they were 00:14:57.059 --> 00:15:00.259 mythologized. Cultures around the world gave 00:15:00.259 --> 00:15:03.179 names and stories to the constellations, turning 00:15:03.179 --> 00:15:07.419 the night sky into a canvas of meaning. The Pleiades, 00:15:07.600 --> 00:15:10.399 or Seven Sisters, appear in Greek, Japanese, 00:15:10.759 --> 00:15:14.860 and Aboriginal lore. The Greek version of Orion 00:15:14.860 --> 00:15:17.860 the Hunter is mirrored in myths from the Americas 00:15:17.860 --> 00:15:21.799 and Africa, often with similar traits. Chasing. 00:15:21.929 --> 00:15:26.250 boasting or falling. The Inuit interpret Orion 00:15:26.250 --> 00:15:30.289 as a caribou hunter. The Greeks imagined Scorpius 00:15:30.289 --> 00:15:33.370 chasing Orion, which is why they appear on opposite 00:15:33.370 --> 00:15:36.789 sides of the sky. And the Milky Way itself might 00:15:36.789 --> 00:15:40.289 be a road, a river, a trail of birds, or the 00:15:40.289 --> 00:15:42.690 backbone of night, depending on where you're 00:15:42.690 --> 00:15:46.649 standing. The night sky is part calendar, part 00:15:46.649 --> 00:15:50.850 compass, and part sacred text. And maybe that's 00:15:50.850 --> 00:15:54.269 the biggest through line of all. Ancient astronomy 00:15:54.269 --> 00:15:58.190 wasn't some esoteric discipline. It was life. 00:15:58.889 --> 00:16:01.490 Watching the sky meant understanding your place 00:16:01.490 --> 00:16:05.090 in time, your duties to the community, and your 00:16:05.090 --> 00:16:07.549 connection to something larger than yourself. 00:16:08.870 --> 00:16:11.649 So today, when we glance at an app to check the 00:16:11.649 --> 00:16:14.929 phase of the moon or use GPS to navigate a back 00:16:14.929 --> 00:16:18.879 road, It's easy to forget how deep our relationship 00:16:18.879 --> 00:16:22.399 with the sky runs. But every time we look up, 00:16:22.480 --> 00:16:25.480 we're tapping into an ancient tradition. One 00:16:25.480 --> 00:16:28.960 that crosses borders, bridges millennia, and 00:16:28.960 --> 00:16:31.700 ties us to the people who built stone circles, 00:16:32.279 --> 00:16:35.879 carved eclipse charts into clay, or sang the 00:16:35.879 --> 00:16:39.600 constellations into memory. We're not just watching 00:16:39.600 --> 00:16:43.139 the sky. We're participating in humanity's oldest 00:16:43.139 --> 00:16:50.899 shared story. If the stars spoke to you this 00:16:50.899 --> 00:16:53.500 week, or if a question's been on your mind, I'd 00:16:53.500 --> 00:16:56.799 love to hear it. Visit our website, StarTrails 00:16:56.799 --> 00:17:00.519 .Show, where you can contact me and explore past 00:17:00.519 --> 00:17:04.220 episodes. Be sure to follow us on Mastodon, Blue 00:17:04.220 --> 00:17:07.640 Sky, and YouTube. Links are in the show notes. 00:17:08.380 --> 00:17:11.059 Until we meet again beneath the stars, clear 00:17:11.059 --> 00:17:11.920 skies everyone.