Latest / Star Trails: From Backyard Astronomy to Cosmic Wonder / The Sturgeon Moon and the Fossil in the Dark

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The Sturgeon Moon and the Fossil in the Dark · 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
• 0:14
  to the night sky for the week starting August
• 0:16
  3rd to the 9th. This week brings us a bright
• 0:20
  summer moon, planets in both the evening and
• 0:23
  morning skies, and a few lingering meteors. Later
• 0:28
  in the episode, we'll head to the frozen frontier
• 0:31
  of the solar system to meet a brand new world,
• 0:34
  nicknamed Ammonite, and explore what it means
• 0:37
  for the ongoing mystery of Planet Nine. So let's
• 0:41
  step outside and see what's happening overhead.
• 0:47
  Our first stop is always the Moon. Tonight it's
• 0:50
  a waxing gibbous, about 69 % illuminated. If
• 0:54
  you head out shortly after sunset, you'll find
• 0:57
  it sliding just beneath Antares, the bright red
• 1:00
  heart of Scorpius, making a perfect binocular
• 1:03
  target. Each night the moon grows fatter and
• 1:07
  brighter. By Saturday, August the 9th, we reach
• 1:10
  the full sturgeon moon. It rises already brilliant
• 1:14
  in the early evening. The sturgeon moon is the
• 1:18
  traditional name for the full moon in August,
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  and it comes from Native American and colonial
• 1:23
  folklore, particularly from the Great Lakes and
• 1:27
  northeastern North America. According to Algonquin
• 1:31
  and other indigenous tribes in the northeastern
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  U .S. and parts of Canada, August was the time
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  of year when sturgeon were most readily caught
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  in the Great Lakes and other large bodies of
• 1:42
  water. These massive ancient fish, some of which
• 1:46
  can grow more than six feet long, would surface
• 1:49
  in greater numbers during this time, making them
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  easier to harvest. As a result, tribes that relied
• 1:55
  on fishing for sustenance saw August as a season
• 1:59
  of abundance, and they marked the full moon of
• 2:02
  this time with a name reflecting the height of
• 2:04
  the sturgeon fishing season. Binocular and telescope
• 2:08
  users will want to get in their observations
• 2:11
  early this week, especially if you want to see
• 2:13
  craters and mountain ranges along the lunar terminator.
• 2:18
  This week's planets are split between evening
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  and dawn. Mars is fading into the western twilight,
• 2:24
  a small orange ember low on the horizon. Saturn
• 2:28
  rises in the east -southeast after sunset and
• 2:31
  remains visible all night. Through a telescope,
• 2:34
  its rings are stunning, and Neptune lurks nearby,
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  a faint bluish dot best seen with optics. Just
• 2:43
  shift slightly up one to two degrees from Saturn
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  to locate Neptune. In the pre -dawn sky, the
• 2:50
  real show begins. Venus dominates as the morning
• 2:54
  star blazing over the eastern horizon. Jupiter
• 2:58
  shines nearby, and the two planets inch closer
• 3:01
  each morning heading toward a tight conjunction
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  on August 12. Uranus is faint but trackable just
• 3:08
  below the Pleiades star cluster. This is a good
• 3:12
  binocular challenge for dedicated early risers.
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  The Southern Delta Aquarid and Alpha Capricornid
• 3:20
  meteor showers are tapering off this week. You
• 3:23
  might catch a handful of lingering streaks early
• 3:25
  in the week, with the Alpha Capricornids occasionally
• 3:29
  producing a bright fireball. The Perseids are
• 3:32
  already active and will peak next week around
• 3:35
  August 12th or 13th, but a bright moon will wash
• 3:39
  out many fainter meteors. Even so, pre -dawn
• 3:42
  observers under dark skies can still spot some
• 3:45
  early Perseids tracing long paths across the
• 3:49
  sky. Looking deeper into the cosmos, check out
• 3:53
  a few open clusters in Auriga, like M36, M37,
• 3:59
  and M38. They're visible overhead in the early
• 4:03
  evening. Auriga is high after dark and rich with
• 4:06
  bright stars like Capella. Scorpius crouches
• 4:10
  low in the southwest with Antares glowing red.
• 4:14
  Early in the week, watch the moon drift past
• 4:17
  it. In very dark areas, look along the Milky
• 4:20
  Way from Cygnus through Sagittarius. This region
• 4:24
  is rich with star clouds, dark nebula, and the
• 4:28
  Sagittarius teapot asterism pointing to the galactic
• 4:32
  center. Aim a small telescope or binoculars along
• 4:36
  this Milky Way stretch, where open clusters like
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  M7 in Scorpius and M11 in Scutum sparkle amid
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  the star fields. Coming up, a distant relic of
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  the solar system is proving to be a bit of a
• 4:51
  troublemaker, shaking up theories that point
• 4:54
  to the existence of the fabled Planet Nine. That's
• 4:57
  after the break. Stay with us. This week we're
• 5:12
  venturing far beyond Neptune into the quiet frozen
• 5:16
  frontier of the solar system, where astronomers
• 5:19
  have discovered a mysterious new world. Its official
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  name is 2023 KQ14, but scientists call it Ammonite
• 5:30
  after the coiled fossil. And its orbit is challenging
• 5:34
  one of the most tantalizing ideas in planetary
• 5:37
  science, the search for Planet Nine. Ammonite
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  was discovered in March 2023 by astronomers using
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  Japan's Subaru telescope on Mauna Kea. Recently
• 5:50
  detailed in a Nature astronomy paper published
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  just last month, Ammonite's orbit is a highly
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  elongated, tilted trajectory, stretching from
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  66 AU at closest to more than 250 AU at farthest.
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  That's hundreds of times farther from the Sun
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  than Earth. Ammonite is estimated to be around
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  220 to 380 kilometers across, making it comparable
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  in size to other mid -sized trans -Neptunian
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  objects. Not Pluto -class, but substantial enough
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  to merit the dwarf planet tag. Interestingly,
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  its orbit has remained stable for roughly four
• 6:31
  and a half billion years, making it a cosmic
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  fossil of the early solar system. What might
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  it look like? Well, picture a dark reddish -brown
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  icy world, like a charcoal -toned snowball. Its
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  surface is probably a mix of frozen water and
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  rock, cratered and rugged after billions of years
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  in deep freeze. In sunlight, a few patches of
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  bright frost might glimmer on its horizon. No
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  telescope on Earth can show us any details yet.
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  It's far too small and faint, but its orbit tells
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  its story. Ammonite is part of an elite family
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  of worlds called Sednoids. Only three others
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  are known, Sedna, Leila Kahuna, and one other
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  smaller object called 2012 VP. All of them live
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  beyond Neptune's influence, like fossils of the
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  early solar system, untouched for billions of
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  years. These objects suggest the presence of
• 7:31
  the elusive Planet Nine, a hypothetical object
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  of maybe five to ten Earth masses orbiting hundreds
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  of AU from the Sun. Its gravity could shepherd
• 7:42
  small icy bodies into similar orbits, creating
• 7:45
  a cluster pointing in the same direction. But
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  here's the twist. Ammonite doesn't line up with
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  the cluster. Its orbit points almost the opposite
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  way, which weakens the main piece of evidence
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  for the existence of Planet Nine. Does that mean
• 8:02
  Planet Nine isn't real? Well, maybe. Or maybe
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  it's farther out or on a different orbit than
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  we imagined. The good news is we're entering
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  a golden age for discoveries like this. Over
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  the next couple of years, the Vera C. Rubin Observatory
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  will begin the legacy survey of space and time.
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  creating a decade -long movie of the night sky.
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  It's expected to reveal hundreds of new distant
• 8:29
  objects, giving us the numbers we need to confirm
• 8:32
  or refute Planet Nine once and for all. No doubt
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  there are many more tiny frozen worlds like Ammonite
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  silently orbiting at the edge of our solar system.
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  They are fossils of our solar system's youth,
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  and each one whispers a story that might lead
• 8:49
  us to the next great discovery. If the stars
• 8:57
  spoke to you this week, or if a question's been
• 8:59
  on your mind, I'd love to hear it. Visit our
• 9:02
  website, StarTrails .Show, where you can contact
• 9:05
  me and explore past episodes. Be sure to follow
• 9:09
  us on Blue Sky and YouTube. Links are in the
• 9:13
  show notes. Until we meet again beneath the stars,
• 9:16
  clear skies everyone.