Latest / Star Trails: From Backyard Astronomy to Cosmic Wonder / Erased from the Charts, but Still Etched in the Stars

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Erased from the Charts, but Still Etched in the Stars · Star Trails: From Backyard Astronomy to Cosmic Wonder

• 0:07
  Howdy Star Gazers and welcome to this episode
• 0:10
  of Star Trails. Drew here and I'll be your guide
• 0:13
  to the night sky for the week starting May 18th
• 0:16
  through the 24th. This week the moon wanes and
• 0:21
  the early morning sky comes alive. We'll also
• 0:24
  take a journey back into history and learn about
• 0:27
  one of the largest constellations in the sky,
• 0:30
  and why it doesn't exist anymore. Also, did you
• 0:34
  know there was once a house cat in the sky? More
• 0:37
  on that later. Whether you're tuning in from
• 0:40
  the backyard, the balcony, or just your imagination,
• 0:43
  I'm glad you're here. So find a cozy spot, let
• 0:47
  your eyes adjust, and let's see what the sky
• 0:50
  holds for us this week. Let's start with the
• 0:54
  moon. On May 18th, it's in a waning gibbous phase,
• 0:58
  still bright in the sky but shrinking each night.
• 1:01
  By the 20th, we hit the last quarter, meaning
• 1:04
  the moon rises around midnight and leaves us
• 1:07
  with dark skies after it sets. And by the end
• 1:11
  of the week, we're deep into the waning crescent
• 1:13
  phase, which means prime conditions for hunting
• 1:17
  faint galaxies and star clusters. Now onto the
• 1:21
  planets. In the evening Jupiter is hanging low
• 1:24
  in the western sky after sunset. It's getting
• 1:28
  closer to the sun's glare each night, so catch
• 1:31
  it while you can. Mars is much easier to spot,
• 1:35
  glowing reddish high overhead after dark. It's
• 1:39
  a great target this week, especially with less
• 1:41
  moonlight to compete. If you're an early riser,
• 1:46
  the morning sky has even more going on. Venus
• 1:49
  is blazing away in the eastern pre -dawn hours.
• 1:53
  It's the brightest thing in the sky other than
• 1:55
  the moon. Look above it and you'll find Saturn,
• 1:59
  more subdued but still visible without a telescope.
• 2:02
  And just before sunrise, try spotting Mercury.
• 2:06
  It's hugging the eastern horizon and can be tricky,
• 2:09
  but it's worth the challenge. Meanwhile, spring
• 2:13
  constellations are still putting on a show. Look
• 2:16
  south for Virgo and Leo, or trace the arc of
• 2:20
  Boötes, where bright orange Arcturus anchors
• 2:24
  the view. This is also a fantastic week to aim
• 2:27
  for deep -sky gems like M13 in Hercules or M5
• 2:33
  in Serpens, especially now that the moon isn't
• 2:36
  hogging the spotlight. Before we get into the
• 2:47
  second half of the show, I have a little housekeeping
• 2:49
  to discuss. As we end May and head into summer,
• 2:54
  astronomy starts becoming difficult for many
• 2:56
  of us. Moving towards the summer solstice, the
• 2:59
  days will grow much longer, affording us less
• 3:02
  observation time. Increased heat and crazy summer
• 3:06
  weather can be a problem for some of us. For
• 3:10
  example, here in the southeast U .S., summer
• 3:12
  brings haze, humidity, and daily thunderstorms.
• 3:16
  Not to mention 90 degree temperatures, mosquitoes,
• 3:20
  and other pests. So all this to say, I won't
• 3:23
  be doing a lot of observation for the next 3
• 3:26
  or 4 months. I haven't decided if the show will
• 3:29
  continue to be weekly during the summer or whether
• 3:33
  I'll try releasing every 2 weeks. If you have
• 3:36
  any opinions on this, go to StarTrails .Show
• 3:39
  and let me know. Also, last year, right before
• 3:44
  our December break, I mentioned that I would
• 3:47
  be reading Nightwatch, a practical guide to viewing
• 3:50
  the universe, by Terence Dickinson. This is a
• 3:54
  popular book for backyard astronomers. Well,
• 3:58
  sadly, I never got around to reading it, so I
• 4:01
  apologize to anyone who was hoping for a Star
• 4:03
  Trails book club moment. I do plan to start reading
• 4:07
  it soon, especially since observation will be
• 4:10
  rough for me in the coming weeks. I'll report
• 4:13
  back with my thoughts on this book in a future
• 4:15
  episode. This book is often cited as a must -read
• 4:20
  for backyard astronomers, so be sure to get the
• 4:23
  fifth edition, which is the latest version. Today
• 4:32
  we're going to discuss some constellations of
• 4:35
  the southern sky. Regular listeners know that
• 4:39
  we generally focus on the skies over North America,
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  so this may be unfamiliar territory. I was once
• 4:46
  told by an astronomer that the southern hemisphere
• 4:49
  wasn't as impressive as the northern. He said,
• 4:53
  and I quote, all they have are some Magellanic
• 4:56
  clouds. This couldn't be farther from the truth.
• 4:59
  I once spent several weeks in Australia, and
• 5:02
  one night in the country I was able to see a
• 5:05
  stunningly dark, clear night sky filled with
• 5:08
  dazzling, unfamiliar patterns. While the northern
• 5:12
  sky is home to some of the most iconic and familiar
• 5:15
  constellations, like Ursa Major, Orion, and Cassiopeia,
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  it offers a more edge -on view of the Milky Way.
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  That means we see a thinner, less dense section
• 5:27
  of our galaxy, but it's rich in recognizable
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  shapes and nearby objects like the Andromeda
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  Galaxy and the Pleiades Cluster. Polaris, the
• 5:37
  North Star, also makes navigation easy, and centuries
• 5:41
  of mythology have helped etch these constellations
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  deep into cultural memory. But head south and
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  the sky explodes with drama. The Southern Hemisphere
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  gives us a direct line of sight to the galactic
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  core, where the Milky Way appears brighter, denser,
• 5:59
  and far more intricate. It hosts the Southern
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  Cross, the dazzling Carina Nebula, which we'll
• 6:06
  discuss in a moment, the massive Omega Centauri
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  Cluster, and even entire satellite galaxies,
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  the large and small Magellanic Clouds that my
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  astronomer friend was so dismissive of. The reason
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  I mention this is because the southern sky was
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  home to a fascinating constellation that doesn't
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  exist anymore. There's actually a whole cast
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  of constellations that used to exist and don't
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  anymore. And none of them were quite as grand
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  or as doomed as Argo Navus, the ship that got
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  sunk by astronomers. This was once a constellation
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  so big, so sprawling, it had to be broken up
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  like a decommissioned schooner at a shipyard.
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  Argo Navus was named after the mythical ship
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  Argo, the one Jason and the Argonauts sailed
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  on during their legendary quest for the Golden
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  Fleece. This is classic Greek mythology. The
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  constellation was first catalogued by Claudius
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  Ptolemy in the 2nd century CE, during the golden
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  age of ancient astronomy. Back then, they weren't
• 7:14
  too concerned with how huge this thing was. It
• 7:17
  sprawled across a massive chunk of the southern
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  sky. To give you an idea of its size, if you
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  took Orion, Canis Major, and Gemini, and smashed
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  them all into one mega constellation, that's
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  the scale we're talking about. For centuries,
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  Argo Navus stood as the largest single constellation
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  in the sky, but it had a problem. Simply, it
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  was really, really impractical. By the 1700s,
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  astronomers started to feel like Argo Navis was
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  less of a constellation and more of a mess. It
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  had hundreds of stars and no clear borders. Trying
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  to map or reference anything inside it was like
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  trying to navigate a ship with three captains
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  shouting different directions. Enter Nicolas
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  -Louis Delacay, an 18th century French astronomer.
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  He was mapping the southern skies from the Cape
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  of Good Hope in South Africa. In 1763, Lakai
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  decided enough was enough. He chopped Argo Navus
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  into three new nautical -themed constellations,
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  and they've stuck ever since. There's Carina,
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  the keel of the ship. Pupus, the stern, also
• 8:35
  known as the poop deck, and Vela, the sails.
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  And just like that, the mighty Argo Navus was
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  no more. Of course, just because the name disappeared
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  doesn't mean the stars did. These three new constellations
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  inherited all kinds of celestial treasures. Carina
• 8:55
  is home to Canopus, the second brightest star
• 8:58
  in the night sky, just behind Sirius. For viewers
• 9:02
  in the Southern Hemisphere, Canopus is a brilliant
• 9:05
  white beacon low on the horizon. Deep in Carinna
• 9:09
  lies the Carinna Nebula, one of the largest star
• 9:13
  -forming regions visible from Earth. Inside it,
• 9:16
  we find the massive and unstable Etta Carini,
• 9:20
  a binary star system so volatile it once brightened
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  the sky in the 1800s to become the second brightest
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  star for a time. Let's drift over to Vela. Its
• 9:31
  most famous feature is the Vela Supernova Remnant,
• 9:35
  a massive bubble of gas and dust left behind
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  by a star that exploded about 11 ,000 years ago.
• 9:43
  Its ghost is still expanding through space. Inside
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  the remnant is the Vela Pulsar, a rapidly spinning
• 9:52
  neutron star beaming out radio waves like a cosmic
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  lighthouse. Pupus is home to Messier 93, an open
• 10:02
  -star cluster tightly packed with hot young stars.
• 10:06
  There's also NGC 2467, a vibrant nebula sometimes
• 10:12
  called the Skull and Crossbones Nebula. Despite
• 10:15
  its eerie nickname, it's actually a stellar nursery.
• 10:20
  So even though Argonavis, as a name, is gone,
• 10:23
  its pieces are alive and well. filled with some
• 10:26
  of the most dazzling and active regions of the
• 10:29
  Milky Way. Of course, Argo wasn't the only constellation
• 10:33
  to get the axe. Here are a few other sky figures
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  that were edited out of the final draft. Quadrons
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  Morales was a northern hemisphere constellation
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  created in the 18th century and named after a
• 10:47
  wall -mounted astronomical instrument, the quadrant.
• 10:51
  It no longer exists officially, but its name
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  survives in the quadrantid meteor shower that
• 10:57
  peaks in early January. Felis, the cat, was a
• 11:02
  house cat in the sky. It was introduced by French
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  astronomer Joseph -Jérôme de la Londe in 1799
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  because, as he put it, cats deserve to be represented.
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  The IAU disagreed and poor Phelous got booted
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  in 1922. The constellation was located near Hydra.
• 11:26
  While it's not acknowledged anymore, its brightest
• 11:28
  star, Phelous, is a reminder that it existed
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  and is quite an interesting star in its own right.
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  Located more than 600 light years from Earth,
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  Felis is an orange -red giant with a high proper
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  motion. That's the apparent movement of the star
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  compared to others in the sky. And finally, Antinous
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  is another constellation that was quietly retired.
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  A tragic figure from Roman history, Antinous
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  was Hadrian's young lover. He was later deified
• 12:02
  and immortalized as a star pattern. The constellation
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  was removed from charts in 1922 and became part
• 12:10
  of the constellation Aquila. More recently, the
• 12:14
  IAU working group on star names approved the
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  name Antinous for the star Theta Aquili in 2024
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  in honor of the defunct constellation. If there's
• 12:27
  any lesson here, it's that the sky is always
• 12:29
  evolving. constellations aren't permanent. They're
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  cultural artifacts shaped by who we are, what
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  we believe, and how we explore the universe.
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  They remind us that the tapestry of the cosmos
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  is a mirror of our evolving time here on Earth.
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  If the stars spoke to you this week, or if a
• 12:55
  question's been on your mind, I'd love to hear
• 12:58
  it. visit our website, StarTrails .Show, where
• 13:02
  you can contact me and explore past episodes.
• 13:06
  Be sure to follow us on Mastodon, Blue Sky, and
• 13:10
  YouTube. Links are in the show notes. Until we
• 13:13
  meet again beneath the stars, clear skies everyone.