Latest / Star Trails: From Backyard Astronomy to Cosmic Wonder / A Crown, a Ghost Planet, and a Star That Ate Another Star

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A Crown, a Ghost Planet, and a Star That Ate Another Star · Star Trails: From Backyard Astronomy to Cosmic Wonder

• 0:07
  Howdy stargazers 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 11th
• 0:17
  through the 17th. This week we welcome the Flower
• 0:20
  Moon. We say goodbye to the last remnants of
• 0:24
  the Eta Aquarid meteor shower, and we revisit
• 0:27
  a topic from a previous episode to learn what
• 0:30
  happens when a red giant eats a neutron star.
• 0:34
  The universe can be a very weird place. Whether
• 0:39
  you're tuning in from the backyard, the balcony,
• 0:41
  or just your imagination, I'm glad you're here.
• 0:45
  So find a cozy spot, let your eyes adjust, and
• 0:49
  let's see what the sky holds for us this week.
• 0:54
  Before we take a look at this week's night sky,
• 0:57
  I wanted to briefly mention a topic that's been
• 0:59
  showing up in my news feeds recently, and maybe
• 1:03
  yours too. There have been a number of headlines
• 1:06
  in recent weeks concerning the discovery of what
• 1:09
  could be a candidate for the elusive Planet 9,
• 1:14
  also known as Planet X. A massive, enigmatic
• 1:18
  world in our own solar system lurking somewhere
• 1:21
  out beyond Pluto. The idea of an undiscovered
• 1:26
  planet isn't new. In fact, it stretches back
• 1:29
  more than a century. Early astronomers noticed
• 1:33
  discrepancies in the orbits of Uranus and Neptune
• 1:36
  that led them to suspect another planet was tugging
• 1:40
  on them gravitationally. This theoretical body
• 1:44
  was often referred to as Planet X. While Pluto
• 1:48
  was discovered in 1930 during that search, it
• 1:51
  was quickly deemed too small to explain the gravitational
• 1:55
  anomalies, and the mystery persisted. Fast forward
• 1:59
  to 2016. A pair of Caltech astronomers, Mike
• 2:04
  Brown and Konstantin Batygin, reignited the Planet
• 2:08
  9 discussion. They were looking at the odd clustering
• 2:12
  of several distant trans -Neptunian objects,
• 2:15
  or TNOs, icy bodies way out in the Kuiper Belt
• 2:20
  and beyond. Their orbits seemed to be shepherded
• 2:23
  by something massive. The best explanation was
• 2:28
  a yet undiscovered planet at least five to ten
• 2:31
  times the mass of Earth, orbiting far beyond
• 2:35
  Pluto on a highly elliptical, tilted path. If
• 2:39
  real, this ninth planet would take 10 ,000 to
• 2:43
  20 ,000 years to complete a single orbit. Since
• 2:48
  then, astronomers have been combing sky surveys
• 2:51
  and telescope archives looking for any sign of
• 2:54
  this ghostly planet, and just recently there's
• 2:58
  been a possible breakthrough. Using infrared
• 3:02
  data from two old space missions, NASA's IRIS
• 3:06
  satellite from 1983 and Japan's Akari Observatory
• 3:11
  from the 2000s, researchers may have spotted
• 3:15
  a faint object moving slowly across the sky in
• 3:19
  images taken 23 years apart. That kind of motion,
• 3:24
  combined with its faintness, is exactly what
• 3:27
  you'd expect from a distant planet orbiting hundreds
• 3:31
  of times farther from the Sun than Earth. This
• 3:35
  candidate object appears to be roughly the right
• 3:38
  mass, somewhere between 5 and 10 Earth masses.
• 3:42
  Its orbit seems to be tilted about 120 degrees
• 3:46
  relative to the plane of the solar system. That's
• 3:50
  far more extreme than what the Planet 9 model
• 3:53
  predicts, which puts the tilt more around 15
• 3:56
  to 25 degrees, because remember our solar system
• 4:00
  is largely flat. In other words, this might not
• 4:03
  be THE Planet 9, but it could be A Planet 9,
• 4:08
  a new unknown planetary body in the far outer
• 4:12
  solar system. Mike Brown, the same astronomer
• 4:16
  who helped revive the Planet 9 theory, has expressed
• 4:20
  skepticism about this new candidate. He points
• 4:23
  out that the extreme tilt doesn't match what
• 4:26
  they expected. Still, the discovery is intriguing
• 4:30
  and adds fuel to the idea that we really don't
• 4:33
  know everything about what's lurking in the solar
• 4:36
  system's deep freeze. We're expecting a lot more
• 4:40
  clarity in the coming years. The Vera C. Rubin
• 4:44
  Observatory in Chile, set to begin operations
• 4:47
  soon, will conduct an incredibly deep, wide -field
• 4:51
  sky survey that could either confirm this object
• 4:54
  or uncover something even more compelling. So,
• 4:58
  if you've been seeing headlines about Planet
• 5:01
  Nine lately, you're not alone. The hunt is heating
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  up again, and we may be closer than ever to discovering
• 5:08
  a whole new world orbiting in the shadows. And
• 5:12
  if you want to learn more about this search,
• 5:15
  look way back into our archive to episode 14.
• 5:26
  On Monday, we witness May's full moon, traditionally
• 5:31
  known as the Flower Moon. The name originates
• 5:34
  from Native American cultures, notably the Algonquin
• 5:38
  people, who associated the May full moon with
• 5:41
  the abundance of blooming flowers during this
• 5:44
  time of year. This full moon is also a micro
• 5:48
  -moon, occurring when the moon is near its apogee,
• 5:52
  making it appear slightly smaller than usual.
• 5:55
  Despite its size, it will illuminate the night
• 5:58
  sky beautifully. The planets are very much the
• 6:02
  same as they've been for the past few weeks.
• 6:05
  In the evening sky, Jupiter shines brightly in
• 6:08
  the west after sunset, setting before midnight.
• 6:12
  Mars remains reddish and prominent, located higher
• 6:16
  in the sky above Jupiter, passing through Cancer.
• 6:19
  You'll be able to see it until about 2 a .m.
• 6:23
  In the morning sky, Venus remains visible in
• 6:27
  the east after about 4 .30 a .m. until just before
• 6:30
  sunrise. Venus is currently at a very bright,
• 6:35
  negative 4 .3 magnitude, so you can't miss it.
• 6:39
  Venus and Saturn are in a conjunction less than
• 6:43
  10 degrees apart. Look for Saturn a bit above
• 6:46
  and to the right of Venus. It's currently at
• 6:49
  a magnitude of 1. Mercury remains elusive, lost
• 6:54
  in the morning sun's glare. While its peak occurred
• 6:58
  earlier in May, the Etta aquarid meteor shower
• 7:01
  remains active through May 21st. It's best viewed
• 7:05
  in the pre -dawn hours, especially in areas with
• 7:08
  minimal light pollution. These meteors are caused
• 7:12
  by debris from Halley's Comet, and they will
• 7:15
  appear to radiate from the southeast sky, from
• 7:18
  the constellation Aquarius, although you'll be
• 7:21
  able to see them in any portion of the sky. High
• 7:25
  in the eastern sky, you'll find Corona Borealis,
• 7:29
  the northern crown. In Greek mythology, this
• 7:33
  semicircular constellation represents the crown
• 7:37
  of Princess Ariadne of Crete. gifted to her by
• 7:41
  the god Dionysus on their wedding day. After
• 7:45
  her death, Dionysus placed the crown in the heavens
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  to honor her. This constellation is home to the
• 7:52
  blaze star T. coroni borealis, a binary star
• 7:57
  system located about 3 ,000 light years away.
• 8:02
  TCB is a recurrent nova, and we know it's erupted
• 8:06
  at least twice before, in 1866 and in 1946, roughly
• 8:12
  80 years apart. Astronomers anticipate its next
• 8:16
  eruption could occur soon, potentially making
• 8:19
  it visible to the naked eye for about a week,
• 8:22
  about as bright as the star Polaris. Two weeks
• 8:32
  ago on Star Trails, we explored the wild phenomenon
• 8:35
  of runaway stars. Celestial bodies ejected from
• 8:40
  their stellar neighborhoods at incredible speeds,
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  often owing to violent gravitational interactions
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  or supernova kicks. But what happens when a runaway
• 8:51
  star doesn't escape but crashes into another
• 8:54
  star instead? That brings us to one of the weirdest
• 8:58
  and most intriguing star types ever proposed,
• 9:02
  the Thorne -Zitkow object. Back in the 1970s,
• 9:07
  physicist Kip Thorne, who you might know from
• 9:10
  his work on gravitational waves and as the science
• 9:14
  advisor for the film Interstellar, teamed up
• 9:17
  with Polish astrophysicist Anna Zitkow. Together,
• 9:22
  they theorize the existence of a bizarre kind
• 9:25
  of star that could form under extreme circumstances.
• 9:30
  A neutron star, that's the dense core remnant
• 9:33
  of a supernova, merging into a red supergiant.
• 9:39
  The science is mind -bending. A neutron star
• 9:42
  is roughly the size of a city, but contains more
• 9:46
  mass than our sun. If such an object were to
• 9:49
  collide with a red supergiant, it wouldn't just
• 9:52
  pass through. It would sink to the core of the
• 9:56
  larger star, embedding itself there, and essentially
• 9:59
  take over its inner workings. This hybrid part
• 10:04
  -star and part -Frankenstein experiment is what
• 10:08
  we now call a Thorn -Zitkow Object, or TZO. These
• 10:14
  objects are difficult to locate. On the outside,
• 10:17
  they look almost exactly like normal red supergiants.
• 10:21
  But inside, the neutron star is altering the
• 10:24
  star's fusion process in bizarre ways. TZOs are
• 10:29
  expected to produce unusual amounts of certain
• 10:32
  heavy elements like rubidium, molybdenum, and
• 10:36
  lithium that aren't typically abundant in red
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  giants. So far, only one strong candidate has
• 10:44
  emerged, a star known as HV2112, located in the
• 10:49
  small Magellanic cloud. This star shows a chemical
• 10:54
  fingerprint that fits the profile, though some
• 10:57
  scientists argue alternative explanations are
• 11:00
  still on the table. If confirmed, HV2112 would
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  be the first real -life Thorne -Zitkow object
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  ever discovered. A neutron star cocooned inside
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  a swollen red giant envelope, the aftermath of
• 11:16
  a stellar collision or a failed binary. It's
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  essentially a star that died, then was reborn
• 11:24
  inside another, invisible to the eye, yet rewriting
• 11:28
  the physics of its host from within. Eventually,
• 11:32
  it's theorized the star's structure destabilizes
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  and the whole system may collapse into a black
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  hole, leaving behind almost no trace of what
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  once was. If the stars spoke to you this week,
• 11:50
  or if a question's been on your mind, I'd love
• 11:53
  to hear it. Visit our website, StarTrails .Show,
• 11:57
  where you can contact me and explore past episodes.
• 12:01
  Be sure to follow us on Mastodon, Blue Sky, and
• 12:05
  YouTube. Links are in the show notes. Until we
• 12:08
  meet again beneath the stars, clear skies everyone.